Title of Invention

MTO PROCESS BASED ON MEAPO MOLECULAR SIEVES COMBINED WITH AN OCP PROCESS TO MAKE OLEFINS

Abstract The present invention relates to a process to make light olefins from an oxygen-containing, halogenide-containing or sulphur-containing organic feedstock comprising: contacting said oxygen-containing, halogenide-containing or sulphur-containing organic feedstock in a primary reactor with a catalyst made of a metalloaluminophosphate (MeAPO) molecular sieve with lamellar crystal morphology at conditions effective to convert at least a portion of the feedstock to form a first reactor effluent comprising light olefins and a heavy hydrocarbon fraction; separating said light olefins from said heavy hydrocarbon fraction; contacting said heavy hydrocarbon fraction in a second reactor at conditions effective to convert at least a portion of said heavy hydrocarbon fraction to light olefins; wherein said MeAPO has an empirical chemical composition on an anhydrous basis, after synthesis and calcination, expressed by the formula HxMeyAlzPkO2 in which, y+z+k=l x<=y y has a value ranging from 0.0008 to 0.4 and advantageously from 0.005 to 0.18 z has a value ranging from 0.25 to 0.67 and advantageously from 0.38 to 0.55 k has a value ranging from 0.2 to 0.67 and advantageously from 0.36 to 0.54 said molecular sieve having predominantly a plate crystal morphology in which the width (W) and the thickness (T) are such as: W/T is >= 10 and advantageously ranges from 10 to 100.
Full Text MTO PROCESS BASED ON MEAPO MOLECULAR SIEVES COMBINED
WITH AN OCP PROCESS TO MAKE OLEFINS
[Field of the invention]
The present invention relates to an MTO (methanol to olefins) process
based on MeAPO molecular sieves combined with an OCP (olefins cracking
process) process to make olefins. More precisely the MTO process is based on
a metalloaluminophosphate (MeAPO) molecular sieve catalyst with lamellar
crystal morphology. The limited supply and increasing cost of crude oil has
prompted the search for alternative processes for producing hydrocarbon
products. One such process is the conversion of methanol to hydrocarbons and
especially light olefins. The interest in the methanol to olefin (MTO) process is
based on the fact that methanol can be obtained from coal or natural gas by the
production of synthesis gas which is then processed to produce methanol. The
MTO process produces light olefins such as ethylene and propylene as well as
heavy hydrocarbons such as butenes and above. These heavy hydrocarbons
are cracked in an OCP process to give mainly ethylene and propylene.
[Background of the invention]
The MTO process has been described in US 2006 0235251, WO 2005
016856, US 2006 0063956, US 2006 0161035, US 6207872, US 2005
0096214, US 6953767 and US 7067095.
Ethylene and propylene are particularly desirable olefins but it has been
found that their yields in the MTO process are reduced by the production of
medium weight hydrocarbons such as C4, C5 and C6 olefins, as well as some
heavier components. Methods are needed to alter the product distribution in the
MTO process for making light olefins to provide processing flexibility. Methods
are sought to reduce the production of C4, C5 and higher olefins from the MTO
process relative to the production of ethylene and propylene. Therefore an OCP
process is combined with the MTO process to crack the C4, C5 and higher
olefins from the MTO process. Such yield improvements of ethylene and
propylene significantly improve the economies of the methanol to olefins
process.
W01999 018055 relates to a method for increasing light olefin yield
during conversion of oxygenates to olefins comprising: contacting an oxygenate
feed in a first reactor (MTO reactor) with a non-zeolitic molecular sieve catalyst
under first conditions effective to produce a first product comprising light olefins
and a heavy hydrocarbon fraction; separating said light olefins from said heavy
hydrocarbon fraction; feeding said heavy hydrocarbon fraction to a second
reactor; and subjecting said heavy hydrocarbon fraction in said second reactor
to second conditions effective to convert at least a portion of said heavy
hydrocarbons to light olefins. Suitable SAPO's for use in the MTO reactor
include SAPO-11, SAPO-44, SAPO-34, SAPO-17, and SAPO-18. A preferred
zeolite for the auxiliary reactor is ZSM-5.
US 2004 0102667 relates to a process for the production of light olefins
from an oxygenate-containing feed stream. This invention more particularly
refers to a process for increasing yields of light olefins through cracking of
heavier olefins produced in a methanol to olefins process.
It has been discovered that, in a combined MTO OCP process, the use
of a specific catalyst in the MTO reactor leads to very high yields in propylene.
Said specific catalyst is made of metalloaluminophosphate (MeAPO) molecular
sieve with lamellar crystal morphology having an empirical chemical
composition on an anhydrous basis, after synthesis and calcination, expressed
by the formula HxMeyAlzPkO2 wherein,
y+z+k=1
x y has a value ranging from 0.0008 to 0.4 and advantageously from 0.005 to
0.18
z has a value ranging from 0.25 to 0.67 and advantageously from 0.38 to 0.55
k has a value ranging from 0.2 to 0.67 and advantageously from 0.36 to 0.54
said molecular sieve having predominantly a plate crystal morphology in which
the width (W) and the thickness (T) are such as :
W7T is >= 10 and advantageously ranges from 10 to 100.
In a preferred embodiment T is more desirably preferably from 0.04 to 0.07 urn.
Said MeAPO are prepared in the presence of one template, one texture
influencing agent, inorganic metal source, Al and P source, all these ingredients
being in specific proportions, MeAPO with very thin lamellar plate crystal
morphology are obtained. The template can be tetraethylammonium hydroxide
(TEAOH) or an amine. The texture influencing agent can be an alcohol, a diol or
glycerol.
The following prior arts describe MeAPO but they are not in the shape of
thin lamellas. All these prior arts concern MeAPO with lamellar cubic or plate
crystal morphology. In all these prior arts only one template is used. Moreover
the combination MTO-OCP is not described.
US 4,440,871 describes microporous crystalline silicoaluminophosphates
(referred as SAPO) the pores of which are uniform and have nominal diameters
of greater than about 3 Angstroms and whose essential empirical chemical
composition in the as-synthesized and anhydrous form is mR:(Six Aly Pz)O2
wherein "R" represents at least one organic templating agent present in the
intracrystalline pore system; "m" has a value of from 0.02 to 0.3; "m" represents
the moles of "R" present per mole of (Six Aly Pz)O2 ; "x", "y" and "z" represent
the mole fractions of silicon, aluminum and phosphorus respectively, present as
tetrahedral oxides, said mole fractions being such that they are within a specific
area in the ternary diagram Six Aly Pz . Process for preparing said SAPO
comprises forming a reaction mixture containing reactive sources of S1O2, Al2
O3, and P2 O5 and an organic templating agent, said reaction mixture having a
composition expressed in terms of molar oxide ratios of: aR2 0:(Six Aly PZ)02
:bH2O wherein "R" is an organic templating agent; "a" has a value large enough
to constitute an effective amount of "R" and is within the range of greater than 0
to 3; "b" has a value of from zero to 500; "x", "y" and "z" represent the mole
fractions, respectively, of silicon, aluminum and phosphorus in the (Six Aly Pz)O2
constituent and each has a value of at least 0.01 and crystallizing the reaction
mixture thus formed at a temperature of at least 100° C until crystals of the
silicoaluminophosphate are formed.
US 6,207,872 relates to a process for converting methanol to light olefins
comprising contacting the methanol with a catalyst at conversion conditions, the
catalyst comprising a crystalline metallo aluminophosphate molecular sieve
having a chemical composition on an anhydrous basis expressed by an
empirical formula of: (ELxAlyPz)O2 where EL is a metal selected from the group
consisting of silicon, magnesium, zinc, iron, cobalt, nickel, manganese,
chromium and mixtures thereof, "x" is the mole fraction of EL and has a value of
at least 0.005, "y" is the mole fraction of Al and has a value of at least 0. 01, "z"
is the mole fraction of P and has a value of at least 0.01 and x+y+z=1, the
molecular sieve characterized in that it has predominantly a plate crystal
morphology, wherein the average smallest crystal dimension is at least 0.1
micron and has an aspect ratio of less than or equal to 5.
US 6,334,994 relates to a microporous crystalline silico-alumino-
phosphate composition, the theoretical composition of which, on a water-free
basis after synthesis and calcination, is: HwSixAlyPzO2 where w and x have a
value between 0.01 and 0.05 and y and z are values between 0.4 and 0.6,
wherein the composition is a mixed phase product comprising silico-alumino-
phosphates of AEI and CHA structure prepared in one batch crystallization, not
including mere physical mixtures, the product after calcination in air at 550° C
for 4 hours, produces a specific X-ray diffractogram and XRD-profiles.
EP 893159 relates to a method for preparing catalysts comprising silica-
modified crystalline silicoaluminophosphate molecular sieves, which comprises
adding an aluminum alkoxide to an aqueous amine or organic ammonium salt
solution cooled at a temperature of not higher than 20°C, followed by hydrolysis,
until a uniform aqueous aluminum hydroxide colloid or solution is formed,
adding, to the colloid or solution, silica or other Si-source compounds, and
phosphoric acid or other P-source compounds, if desired, along with a metal
source selected from the group of Li, Ti, Zr, V, Cr, Mn, Fe, Co, Zn, Be, Mg, Ca,
B, Ga and Ge, hydrothermally treating the resulting mixture to prepare a
crystalline silicoaluminophosphate molecular sieve, and then modifying the
crystalline silicoaluminophosphate molecular sieve with silica.
US 2005 0096214 (US 6953767) relates to a process for making an
olefin product from an oxygenate feedstock comprising contacting said
oxygenate feedstock with a catalyst comprising a silicoaluminophosphate
molecular sieve comprising at least one intergrown phase of molecular sieves
having AEI and CHA framework types, wherein said intergrown phase has an
AEI/CHA ratio of from about 5/95 to 40/60 as determined by DIFFaX analysis,
using the powder X-ray diffraction pattern of a calcined sample of said
silicoaluminophosphate molecular sieve, under conditions effective to form an
olefin product.
It also describes a method for preparing the molecular sieve of said
process that comprises
(a) combining a reactive source of silicon, a reactive source of
phosphorus and a hydrated aluminum oxide in the presence of an organic
structure directing agent (template) to form a mixture;
(b) mixing and heating continuously the mixture prepared at step a) up to
the crystallization temperature;
(c) maintaining the mixture at the crystallization temperature and under
stirring for a period of time of from 2 to 150 hours;
(d) recovering crystals of the silicoaluminophosphate molecular sieve
(e) wherein the mixture prepared at step a) has a molar composition
within the following ranges:
P2 O5:AI2O3 from 0.6:1 to 1.2:1
SiO2:AI2O3from 0.005:1 to 0.35:1
H2O:AI2O3from 10:1 to 40:1
and the template is a tetraethylammonium compound.
In all these above prior arts only template and/or specific reaction
conditions are used to influence the crystal structure of the material. In the
following US 6,540,970 a template and a solvent of the metal (Me) source are
used. In the examples the organic silicon source is tetraethylorthosilicate. US
6,540,970 relates to a method for making a metalloaluminophosphate (MeAPO)
molecular sieve, said process comprising the steps of:
providing a source of alumina, a source of phosphorus, water, and a
template suitable for forming a MeAPO molecular sieve;
providing a source of metal including metal particles, said metal particles
measuring, in their largest dimension, equal to or less than five nanometers;
providing a water soluble organic solvent capable of solubilizing said
source of metal;
forming a synthesis mixture from said source of alumina, said source of
phosphorus, said water, said template, said source of metal, and said solvent;
and forming a MeAPO molecular sieve from said synthesis mixture.
Desirably, the water soluble organic solvent capable of solubilizing the source of
the metal is selected from the group consisting of sulfoxides and C 1 to C 5
oxygenated hydrocarbons. Desirably, the oxygenated hydrocarbon is selected
from the group consisting of alcohols (branched or normal), ketones, aldehydes,
diols and acids. Useful solvents include one or more solvents selected from the
group consisting of acetone, 1,2-propanediol, 1,3-propanediol, methanol,
ethanol, propanol, isopropanol, butanol, and ethylene glycol. Desirably, the
solvent is an alcohol. The products obtained are isocrystalline spheroidal
particles comprising a SAPO molecular sieve. The particle measures from 0.5
microns to 30 microns in diameter.
[Brief summary of the invention]
The present invention relates to a process to make light olefins from an
oxygen-containing, halogenide-containing or sulphur-containing organic
feedstock comprising :
contacting said oxygen-containing, halogenide-containing or sulphur-containing
organic feedstock in a primary reactor with a catalyst made of a
metalloaluminophosphate (MeAPO) molecular sieve with lamellar crystal
morphology at conditions effective to convert at least a portion of the feedstock
to form a first reactor effluent comprising light olefins and a heavy hydrocarbon
fraction;
separating said light olefins from said heavy hydrocarbon fraction;
contacting said heavy hydrocarbon fraction in a second reactor at conditions
effective to convert at least a portion of said heavy hydrocarbon fraction to light
olefins;
wherein said MeAPO has an empirical chemical composition on an anhydrous
basis, after synthesis and calcination, expressed by the formula HxMeyAlzPkO2
in which,
y+z+k=1
x y has a value ranging from 0.0008 to 0.4 and advantageously from 0.005
to 0.18
z has a value ranging from 0.25 to 0.67 and advantageously from 0.38 to
0.55
k has a value ranging from 0.2 to 0.67 and advantageously from 0.36 to
0.54
said molecular sieve having predominantly a plate crystal morphology in
which the width (W) and the thickness (T) are such as :
W/T is >= 10 and advantageously ranges from 10 to 100.
The present invention also relates to a process to make light olefins from
an oxygen-containing, halogenide-containing or sulphur-containing organic
feedstock comprising :
contacting said oxygen-containing, halogenide-containing or sulphur-containing
organic feedstock in a primary reactor with a catalyst made of a
metalloaluminophosphate (MeAPO) molecular sieve at conditions effective to
convert at least a portion of the feedstock to form a first reactor effluent
comprising light olefins and a heavy hydrocarbon fraction;
separating said light olefins from said heavy hydrocarbon fraction;
contacting said heavy hydrocarbon fraction in a second reactor at conditions
effective to convert at least a portion of said heavy hydrocarbon fraction to light
olefins;
wherein said MeAPO has been prepared by a method comprising :
a) forming a reaction mixture containing a texture influencing agent (TIA),
an organic templating agent (TEMP), at least a reactive inorganic source of
Me02 essentially insoluble in the TIA, reactive sources of Al2 O3 and P2 O5,
b) crystallizing the above reaction mixture thus formed until crystals of the
metalloaluminophosphate are formed,
c) recovering a solid reaction product,
d) washing it with water to remove the TIA and
e) calcinating it to remove the organic template.
[Detailed description of the invention]
With regards to the catalyst of the primary reactor, in a preferred
embodiment T is 0.04 to 0.07 urn.
In a advantageous embodiment y has a value ranging from 0.005 to
0.18, z has a value ranging from 0.38 to 0.55 and k has a value ranging from
0.36 to 0.54.
In a first preferred embodiment y has a value ranging from 0.005 to 0.16,
z has a value ranging from 0.39 to 0.55 and k has a value ranging from 0.37 to
0.54.
In a second preferred embodiment y has a value ranging from 0.011 to
0.16, z has a value ranging from 0.39 to 0.55 and k has a value ranging from
0.37 to 0.54.
In a third preferred embodiment y has a value ranging from 0.011 to
0.14, z has a value ranging from 0.40 to 0.55 and k has a value ranging from
0.38 to 0.54.
In an advantageous embodiment the MeAPO molecular sieves have
essentially a structure CHA or AEI or a mixture thereof. Preferably they have
essentially the structure SAPO 18 or SAPO 34 or a mixture thereof.
About the plate crystal morphology, said plates have advantageously the
shape of a simple polygon comprised in a square. The square's length is named
W. The MeAPO molecular sieves have predominantly a plate crystal
morphology. By predominantly is meant advantageously greater than 50% of
the crystals. Preferably at least 70% of the crystals have a plate morphology
and most preferably at least 90% of the crystals have a plate morphology.
About "essentially" referring to the CHA or AEI structure it means that
advantageously more than 80% by weight, preferably more than 90%, of the
MeAPO of the invention has the structure CHA or AEI or a mixture thereof.
About "essentially" referring to the SAPO 18 or SAPO 34 structure it means that
advantageously more than 80% by weight, preferably more than 90%, of the
MeAPO has the structure SAPO 18 or SAPO 34 or a mixture thereof.
Me is advantageously a metal selected from the group consisting of
silicon, germanium, magnesium, zinc, iron, cobalt, nickel, manganese,
chromium and mixtures thereof. Preferred metals are silicon, magnesium and
cobalt with silicon or germanium being especially preferred.
The MeAPO molecular sieve can be used as itself as a catalyst. In
another embodiment it can be formulated into a catalyst by combining the
molecular sieve with other materials that provide additional hardness or catalytic
activity to the finished catalyst product. Materials which can be blended with the
molecular sieve can be various inert or catalytically active materials, or various
binder materials. These materials include compositions such as kaolin and
other clays, various forms of rare earth metals, alumina or alumina sol, titania,
zirconia, quartz, silica or silica sol, and mixtures thereof. These components are
effective in densifying the catalyst and increasing the strength of the formulated
catalyst. When blended with non-metalloaluminophosphate molecular sieve
materials, the amount of MeAPO which is contained in the final catalyst product
ranges from 10 to 90 weight percent of the total catalyst, preferably 20 to 70
weight percent of the total catalyst.
With regards to a method to make said MeAPO, it can be made by a
method which comprises :
a) forming a reaction mixture containing a texture influencing agent (TIA),
an organic templating agent (TEMP), at least a reactive inorganic source of
MeO2 essentially insoluble in the TIA, reactive sources of AI2 O3 and P2 O5, said
reaction mixture having a composition expressed in terms of molar oxide ratios
of:
TEMP/AI2O3 = 0.3-5 , more desirable 0.5-2
MeO2/Al2O3 = 0.005-2.0, more desirable 0.022-0.8
P2O5/AI2O3 =0.5-2, more desirable 0.8-1.2
TIA/AI2O3= 3-30, more desirable 6-20
b) crystallizing the above reaction mixture thus formed until crystals of the
metalloaluminophosphate are formed,
c) recovering a solid reaction product,
d) washing it with water to remove the TIA and
e) calcinating it to remove the organic template.
In an advantageous embodiment TEMP/AI2O3 = 0.5-2 ; MeO2/AI2O3 =
0.022-0.8; P2O5/AI2O3 = 0.8-1.2 and TIA/AI2O3 = 6-20.
In a first preferred embodiment TEMP/AI2O3 = 0.5-2 ; MeO2/Al2O3 =
0.022-0.7; P2O5/AI2O3 = 0.8-1.2 and TIA/AI2O3 = 6-20.
In a second preferred embodiment TEMP/AI2O3 = 0.7-2 ; MeO2/AI2O3 =
0.05-0.7; P2O5/AI2O3= 0.8-1.2 and TIA/AI2O3= 6-20.
In a third preferred embodiment TEMP/AI2O3 = 0.7-2 ; MeO2/Al2O3 =
0.05-0.6; P2O5/AI2O3= 0.8-1.2 and TIA/AI2O3= 6-20.
With regards to the TIA, mention may be made, by way of example, of
1,2-propanediol, 1,3-propanediol, methanol, ethanol, propanol, isopropanol,
butanol, glycerol or ethylene glycol.
With regards to the organic templating agent, it can be any of those
heretofore proposed for use in the synthesis of conventional zeolitic
aluminosilicates and microporous aluminophosphates. In general these
compounds contain elements of Group VA of the Periodic Table of Elements,
particularly nitrogen, phosphorus, arsenic and antimony, preferably N or P and
most preferably N, which compounds also contain at least one alkyl or aryl
group having from 1 to 8 carbon atoms. Particularly preferred nitrogen-
containing compounds for use as templating agents are the amines and
quaternary ammonium compounds, the latter being represented generally by
the formula R4N+ wherein each R is an alkyl or aryl group containing from 1 to 8
carbon atoms. Polymeric quaternary ammonium salts such as
[(C14H32N2)(OH)2]x wherein "x" has a value of at least 2 are also suitably
employed. Both mono-, di and tri-amines are advantageously utilized, either
alone or in combination with a quaternary ammonium compound or other
templating compound. Representative templating agents include
tetramethylammonium, tetraethylammonium, tetrapropylammonium or
tetrabutylammonium cations; di-n-propylamine, tripropylamine, triethylamine;
diethylamine, triethanolamine; piperidine; morpholine; cyclohexylamine; 2-
methylpyridine; N.N-dimethylbenzylamine; N,N-diethylethanolamine;
dicyclohexylamine; N,N-dimethylethanolamine; choline; N,N'-
dimethylpiperazine; 1,4-diazabicyclo(2,2,2)octane; N-methyldiethanolamine, N-
methylethanolamine; N-methylpiperidine; 3-methylpiperidine; N-
methylcyclohexylamine; 3-methylpyridine; 4-methylpyridine; quinuclidine; N,N'-
dimethyl-1,4-diazabicyclo(2,2,2)octane ion; di-n-butylamine, neopentylamine; di-
n-pentylamine; isopropylamine; t-butylamine; ethylenediamine; pyrrolidine; and
2-imidazolidone. Advantageously organic templating agent is selected among
tetraethylammonium hydroxide (TEAOH), diisopropylethylamine (DPEA),
tetraethyl ammonium salts, cyclopentylamine, aminomethyl cyclohexane,
piperidine, triethylamine, diethylamine, cyclohexylamine, triethyl
hydroxyethylamine, morpholine, dipropylamine, pyridine, isopropylamine di-n-
propylamine, tetra-n-butylammonium hydroxide, diisopropylamine, di-n-
propylamine, n- butylethylamine, di-n-butylamine, and di-n-pentylamine and
combinations thereof. Preferably the template, is a tetraethyl ammonium
compound selected from the group of tetraethyl ammonium hydroxide
(TEAOH), tetraethyl ammonium phosphate, tetraethyl ammonium fluoride,
tetraethyl ammonium bromide, tetraethyl ammonium chloride, tetraethyl
ammonium acetate. Most preferably, the template is tetraethyl ammonium
hydroxide.
With regards to the reactive inorganic source of MeO2 essentially
insoluble in the TIA and relating to silicon, non-limiting examples of useful
inorganic silicon source materials non-soluble in alcohols include, fumed silica,
aerosol, pyrogenic silica, precipitated silica and silica gel.
With regards to the reactive sources of AI2O3 , it can be any aluminum
species capable of being dispersed or dissolved in an aqueous synthesis
solution. Useful sources of alumina are one or more sources selected from the
group consisting of the following: hydrated alumina, organo alumina, in
particularly AI(OiPr)3, pseudo-boehmite, aluminum hydroxide, colloidal alumina,
aluminium halides, aluminium carboxylates, aluminium sulfates and mixtures
thereof.
With regards to the reactive sources of P2O5 , it can be one or more
sources selected from the group consisting of phosphoric acid; organic
phosphates, such as triethyl phosphate, tetraethyl-ammonium phosphate;
aluminophosphates; and mixtures thereof. The phosphorous source should also
be capable of being dispersed or dissolved in an alcohol synthesis solution.
These MeAPO can be prepared by the usual methods of the molecular
sieves synthesis technology provided it is in accordance with the above cited
ratios. The reaction mixture is in the form of a gel. The ratios MeO2/Al2O3 and
P2O5/AI2O3 are selected among the above described advantageous and
preferred ratios and are in accordance with the advantageous and preferred y, z
and k described above. By way of example to make a MeAPO having the y, z
and k according to the second preferred embodiment one has to use the ratios
of the ingredients according to the second preferred embodiment of the method
to make said MeAPO.
With regards to the step b), the reaction mixture obtained by mixing the
reactive sources of alumina, MeO2, phosphorus, organic templating agent and
TIA is submitted to autogenous pressure and elevated temperature. The
reaction mixture is heated up to the crystallization temperature that may range
from about 120°C. to 250°C., preferably from 130°C. to 225°C, most preferably
from 150°C. to 200°C. Heating up to the crystallization temperature is typically
carried for a period of time ranging from about 0.5 to about 16 hours, preferably
from about 1 to 12 hours, most preferably from about 2 to 9 hours. The
temperature may be increased stepwise or continuously. However, continuous
heating is preferred. The reaction mixture may be kept static or agitated by
means of tumbling or stirring the reaction vessel during hydrothermal treatment.
Preferably, the reaction mixture is tumbled or stirred, most preferably stirred.
The temperature is then maintained at the crystallization temperature for a
period of time ranging from 2 to 200 hours. Heat and agitation is applied for a
period of time effective to form crystalline product. In a specific embodiment, the
reaction mixture is kept at the crystallization temperature for a period of from 16
to 96 hours.
With regards to the step c), the usual means can be used. Typically, the
crystalline molecular sieve product is formed as a slurry and can be recovered
by standard means, such as by sedimentation, centrifugation or filtration.
With regards to the step d), the separated molecular sieve product is
washed, recovered by sedimentation, centrifugation or filtration and dried.
With regards to the step e), calcination of molecular sieves is known per
se. As a result of the molecular sieve crystallization process, the recovered
molecular sieve contains within its pores at least a portion of the template used.
In a preferred embodiment, activation is performed in such a manner that the
template is removed from the molecular sieve, leaving active catalytic sites with
the microporous channels of the molecular sieve open for contact with a
feedstock. The activation process is typically accomplished by calcining, or
essentially heating the molecular sieve comprising the template at a
temperature of from 200 to 800° C in the presence of an oxygen-containing gas.
In some cases, it may be desirable to heat the molecular sieve in an
environment having a low oxygen concentration. This type of process can be
used for partial or complete removal of the template from the intracrystalline
pore system.
Additionally, if during the synthesis alkaline or alkaline earth metals have
been used, the molecular sieve might be subjected to an ion-exchange step.
Conventionally, ion-exchange is done in aqueous solutions using ammonium
salts or inorganic acids.
With regards to the MTO process in the primary reactor, typically, the
oxygenate feedstock is contacted with the catalyst when the oxygenate is in
vapor phase. Alternately, the process may be carried out in a liquid or a mixed
vapor/liquid phase. In this oxygenate conversion process, olefins can generally
be produced at a wide range of temperatures. An effective operating
temperature range can be from about 200° C. to 700° C. At the lower end of the
temperature range, the formation of the desired olefin products may become
markedly slow. At the upper end of the temperature range, the process may not
form an optimum amount of product. An operating temperature of at least 300°
C, and up to 575° C. is preferred.
The pressure also may vary over a wide range. Preferred pressures are
in the range of about 5 kPa to about 5 MPa, with the most preferred range being
of from about 50 kPa to about 0.5 MPa. The foregoing pressures refer to the
partial pressure of the oxygenate compounds and/or mixtures thereof.
The process can be carried out any system using a variety of transport
beds, although a fixed bed or moving bed system could be used.
Advantageously a fluidized bed is used. It is particularly desirable to operate the
reaction process at high space velocities. The process can be conducted in a
single reaction zone or a number of reaction zones arranged in series or in
parallel. Any standard commercial scale reactor system can be used, for
example fixed bed, fluidised bed or moving bed systems. The commercial scale
reactor systems can be operated at a weight hourly space velocity (WHSV) of
from 0.1 hr-1to1000hr-1.
One or more inert diluents may be present in the feedstock, for example,
in an amount of from 1 to 95 molar percent, based on the total number of moles
of all feed and diluent components fed to the reaction zone. Typical diluents
include, but are not necessarily limited to helium, argon, nitrogen, carbon
monoxide, carbon dioxide, hydrogen, water, paraffins, alkanes (especially
methane, ethane, and propane), aromatic compounds, and mixtures thereof.
The preferred diluents are water and nitrogen. Water can be injected in either
liquid or vapour form.
The oxygenate feedstock is any feedstock containing a molecule or any
chemical having at least an oxygen atom and capable, in the presence of the
above MeAPO catalyst, to be converted to olefin products. The oxygenate
feedstock comprises at least one organic compound which contains at least one
oxygen atom, such as aliphatic alcohols, ethers, carbonyl compounds
(aldehydes, ketones, carboxylic acids, carbonates, esters and the like).
Representative oxygenates include but are not necessarily limited to lower
straight and branched chain aliphatic alcohols and their unsaturated
counterparts. Examples of suitable oxygenate compounds include, but are not
limited to: methanol; ethanol; n-propanol; isopropanol; C4-C20 alcohols; methyl
ethyl ether; dimethyl ether; diethyl ether; di-isopropyl ether; formaldehyde;
dimethyl carbonate; dimethyl ketone; acetic acid; and mixtures thereof.
Representative oxygenates include lower straight chain or branched aliphatic
alcohols, their unsaturated counterparts. Analogously to these oxygenates,
compounds containing sulphur or halides may be used. Examples of suitable
compounds include methyl mercaptan; dimethyl sulfide;; ethyl mercaptan; di-
ethyl sulfide; ethyl monochloride; methyl monochloride, methyl dichloriden-alkyl
halides, n-alkyl sulfides having n-alkyl groups of comprising the range of from
about 1 to about 10 carbon atoms; and mixtures thereof. Preferred oxygenate
compounds are methanol, dimethyl ether, or a mixture thereof. The most
preferred oxygenate compound is methanol.
With regards to the primary reactor effluent, "light olefins" means
ethylene and propylene and the "heavy hydrocarbon fraction" is defined herein
as the fraction containing hydrocarbons having a molecular weight greater than
propane, which means hydrocarbons having 4 carbon atoms or more and
written as C4+. It is desirable to have a 100% conversion of the oxygenate in the
primary reactor. This conversion rate is adjusted by optimization of the
regeneration of the catalyst. Typically in the effluent, and not taking account of
the diluent or the unconverted oxygenate, composition by weight % (the total
being 100%) on carbon basis is as follows :
olefins range from 80 to 98,
paraffins (comprising methane) range from 2 to 20,
dienes range from 0.1 to 0.5,
aromatics are less than 0.5.
Among the olefins, on a 100% basis, the light olefins are from 60 to 95%
for respectively 5 to 40% of olefins with 4 carbon atoms or more. Among the
light olefins the weight ratio propylene/ethylene is higher than 1.1 and
advantageously around 1.1-1.3.
Among the olefins having 4 carbon atoms or more there are 65 to 85
weight % of butenes. More than 85% by weight and advantageously more than
95% of the hydrocarbons having 4 carbon atoms or more are C4 to C8 olefins.
With regards to the OCP process in the second reactor, said process
is known per se. It has been described in EP 1036133, EP 1035915, EP
1036134, EP 1036135, EP 1036136, EP 1036138, EP 1036137, EP 1036139,
EP 1194502, EP 1190015, EP 1194500 and EP 1363983 the content of which
are incorporated in the present invention.
The heavy hydrocarbon fraction produced in the primary reactor (MTO) is
converted in the second reactor, also called an "olefin cracking reactor" or OCP
herein, to produce additional amounts of ethylene and propylene.
Advantageously the catalysts found to produce this conversion comprise a
crystalline silicate of the MFI family which may be a zeolite, a silicalite or any
other silicate in that family or the MEL family which may be a zeolite or any
other silicate in that family. Examples of MFI silicates are ZSM-5 and silicalite.
An example of an MEL zeolite is ZSM-11 which is known in the art. Other
examples are Boralite D and silicalite-2 as described by the International Zeolite
Association ( Atlas of Zeolite Structure Types, 1987, Butterworths). The
preferred crystalline silicates have pores or channels defined by ten oxygen
rings and a high silicon/aluminum atomic ratio.
Crystalline silicates are microporous crystalline inorganic polymers based
on a framework of XO4 tetrahydra linked to each other by sharing of oxygen
ions, where X may be trivalent (e.g. Al, B,. ..) or tetravalent (e.g. Ge, Si, . . .).
The crystal structure of a crystalline silicate is defined by the specific order in
which a network of tetrahedral units are linked together. The size of the
crystalline silicate pore openings is determined by the number of tetrahedral
units, or, alternatively, oxygen atoms, required to form the pores and the nature
of the cations that are present in the pores. They possess a unique combination
of the following properties: high internal surface area; uniform pores with one or
more discrete sizes; ion exchangeability; good thermal stability; and ability to
adsorb organic compounds. Since the pores of these crystalline silicates are
similar in size to many organic molecules of practical interest, they control the
ingress and egress of reactants and products, resulting in particular selectivity
in catalytic reactions. Crystalline silicates with the MFI structure possess a bi-
directional intersecting pore system with the following pore diameters: a straight
channel along [010]: 0.53-0.56 nm and a sinusoidal channel along [100]: 0.51-
0.55 nm. Crystalline silicates with the MEL structure possess a bi-directional
intersecting straight pore system with straight channels along [100] having pore
diameters of 0.53-0.54 nm.
The crystalline silicate catalyst has structural and chemical properties
and is employed under particular reaction conditions whereby the catalytic
cracking of the C4+ olefins readily proceeds. Different reaction pathways can
occur on the catalyst. Under the process conditions, having an inlet temperature
of around 400° to 600°C, preferably from 520° to 600°C, yet more preferably
540° to 580°C, and an olefin partial pressure of from 0.1 to 2 bars, most
preferably around atmospheric pressure. Olefinic catalytic cracking may be
understood to comprise a process yielding shorter molecules via bond
breakage. With such high silicon/aluminum ratio in the crystalline silicate
catalyst, a stable olefin conversion can be achieved with a high propylene yield
on an olefin basis.
The MFI catalyst having a high silicon/aluminum atomic ratio for use in
the second reactor of the present invention may be manufactured by removing
aluminum from a commercially available crystalline silicate. A typical
commercially available silicalite has a silicon/aluminum atomic ratio of around
120. The commercially available MFI crystalline silicate may be modified by a
steaming process which reduces the tetrahedral aluminum in the crystalline
silicate framework and converts the aluminum atoms into octahedral aluminum
in the form of amorphous alumina. Although in the steaming step aluminum
atoms are chemically removed from the crystalline silicate framework structure
to form alumina particles, those particles cause partial obstruction of the pores
or channels in the framework. This inhibits the olefinic cracking processes of the
present invention. Accordingly, following the steaming step, the crystalline
silicate is subjected to an extraction step wherein amorphous alumina is
removed from the pores and the micropore volume is, at least partially,
recovered. The physical removal, by a leaching step, of the amorphous alumina
from the pores by the formation of a water-soluble aluminum complex yields the
overall effect of de-alumination of the MFI crystalline silicate. In this way by
removing aluminum from the MFI crystalline silicate framework and then
removing alumina formed therefrom from the pores, the process aims at
achieving a substantially homogeneous de-alumination throughout the whole
pore surfaces of the catalyst. This reduces the acidity of the catalyst and
thereby reduces the occurrence of hydrogen transfer reactions in the cracking
process. The reduction of acidity ideally occurs substantially homogeneously
throughout the pores defined in the crystalline silicate framework. This is
because in the olefin-cracking process hydrocarbon species can enter deeply
into the pores. Accordingly, the reduction of acidity and thus the reduction in
hydrogen transfer reactions which would reduce the stability of the MFI catalyst
are pursued throughout the whole pore structure in the framework. The
framework silicon/aluminum ratio may be increased by this process to a value of
at least about 180, preferably from about 180 to 1000, more preferably at least
200, yet more preferably at least 300 and most preferably around 480.
The MEL or MFI crystalline silicate catalyst may be mixed with a binder,
preferably an inorganic binder, and shaped to a desired shape, e. g. extruded
pellets. The binder is selected so as to be resistant to the temperature and other
conditions employed in the catalyst manufacturing process and in the
subsequent catalytic cracking process for the olefins. The binder is an inorganic
material selected from clays, silica, metal oxides such as Zr02 and/or metals, or
gels including mixtures of silica and metal oxides. The binder is preferably
alumina-free, although aluminum in certain chemical compounds as in AlPOVs
may be used as the latter are quite inert and not acidic in nature. If the binder
which is used in conjunction with the crystalline silicate is itself catalytically
active, this may alter the conversion and/or the selectivity of the catalyst.
Inactive materials for the binder may suitably serve as diluents to control the
amount of conversion so that products can be obtained economically and
orderly without employing other means for controlling the reaction rate. It is
desirable to provide a catalyst having a good crush strength. This is because in
commercial use, it is desirable to prevent the catalyst from breaking down into
powder-like materials. Such clay or oxide binders have been employed normally
only for the purpose of improving the crush strength of the catalyst. A
particularly preferred binder for the catalyst of the present invention comprises
silica or AIPO4.
The relative proportions of the finely divided crystalline silicate material
and the inorganic oxide matrix of the binder can vary widely. Typically, the
binder content ranges from 5 to 95% by weight, more typically from 20 to 50%
by weight, based on the weight of the composite catalyst. Such a mixture of
crystalline silicate and an inorganic oxide binder is referred to as a formulated
crystalline silicate.
In mixing the catalyst with a binder, the catalyst may be formulated into
pellets, spheres, extruded into other shapes, or formed into a spray-dried
powder. In the catalytic cracking process of the second reactor, the process
conditions are selected in order to provide high selectivity towards propylene or
ethylene, as desired, a stable olefin conversion over time, and a stable olefinic
product distribution in the effluent. Such objectives are favored by the use of a
low acid density in the catalyst (i.e. a high Si/AI atomic ratio) in conjunction with
a low pressure, a high inlet temperature and a short contact time, all of which
process parameters are interrelated and provide an overall cumulative effect.
The process conditions are selected to disfavour hydrogen transfer reactions
leading to the formation of paraffins, aromatics and coke precursors. The
process operating conditions thus employ a high space velocity, a low pressure
and a high reaction temperature. The LHSV ranges from 5 to 30 hr-1 preferably
from 10 to 30 hr-1. The olefin partial pressure ranges from 0.1 to 2 bars,
preferably from 0.5 to 1.5 bars (absolute pressures referred to herein). A
particularly preferred olefin partial pressure is atmospheric pressure (i.e. 1 bar).
The heavy hydrocarbon fraction feedstock is preferably fed at a total inlet
pressure sufficient to convey the feedstocks through the reactor. Said feedstock
may be fed undiluted or diluted in an inert gas, e.g. nitrogen or steam.
Preferably, the total absolute pressure in the second reactor ranges from 0.5 to
10 bars. The use of a low olefin partial pressure, for example atmospheric
pressure, tends to lower the incidence of hydrogen transfer reactions in the
cracking process, which in turn reduces the potential for coke formation which
tends to reduce catalyst stability. The cracking of the olefins is preferably
performed at an inlet temperature of the feedstock of from 400° to 650°C, more
preferably from 450° to 600°C, yet more preferably from 540°C to 590°C,
typically around 560° to 585°C.
In order to maximize the amount of ethylene and propylene and to
minimize the production of methane, aromatics and coke, it is desired to
minimize the presence of diolefins in the feed. Diolefin conversion to monoolefin
hydrocarbons may be accomplished with a conventional selective
hy'drogenation process such as disclosed in U.S. Pat. No. 4,695,560 hereby
incorporated by reference.
The second reactor can be a fixed bed reactor, a moving bed reactor or a
fluidized bed reactor. A typical fluid bed reactor is one of the FCC type used for
fluidized-bed catalytic cracking in the oil refinery. A typical moving bed reactor is
of the continuous catalytic reforming type. As described above, the process may
be performed continuously using a pair of parallel "swing" reactors. The heavy
hydrocarbon fraction cracking process is endothermic; therefore, the reactor
should be adapted to supply heat as necessary to maintain a suitable reaction
temperature. Online or periodic regeneration of the catalyst may be provided by
any suitable means known in the art.
The various preferred catalysts of the second reactor have been found to
exhibit high stability, in particular being capable of giving a stable propylene yield
over several days, e.g. up to ten days. This enables the olefin cracking process to
be performed continuously in two parallel "swing" reactors wherein when one
reactor is operating, the other reactor is undergoing catalyst regeneration. The
catalyst can be regenerated several times.
The second reactor effluent comprises methane, light olefins and
hydrocarbons having 4 carbon atoms or more. Advantageously said second
reactor effluent is sent to a fractionator and the light olefins are recovered.
Advantageously the hydrocarbons having 4 carbon atoms or more are recycled at
the inlet of the second reactor, optionally mixed with the heavy hydrocarbon
recovered from the effluent of the first reactor. Advantageously, before recycling
said hydrocarbons having 4 carbon atoms or more at the inlet of the second
reactor, said hydrocarbons having 4 carbon atoms or more are sent to a second
fractionator to purge the heavies. In a preferred embodiment the light olefins
recovered from the effluent of the first reactor and the light olefins recovered from
the fractionator following the second reactor are treated in a common recovery
section.
Optionally, in order to adjust the propylene to ethylene ratio of the whole
complex, ethylene in whole or in part can be recycled over the second reactor
and advantageously converted into more propylene. This ethylene can either
come from the fractionation section of the first reactor or from the second
reactor.
Optionally, the ethylene in whole or in part coming from either the first or
the second reactor can be recycled over the first reactor where it combines with
methanol to form more propylene. These ways of operation allow to respond
with the same equipment and catalyst to market propylene to ethylene demand.
With regards to another embodiment of the invention, said
embodiment relates to a process to make light olefins from an oxygen-
containing, halogenide-containing or sulphur-containing organic feedstock
comprising :
contacting said oxygen-containing, halogenide-containing or sulphur-containing
organic feedstock in a primary reactor with a catalyst made of a
metalloaluminophosphate (MeAPO) molecular sieve at conditions effective to
convert at least a portion of the feedstock to form a first reactor effluent
comprising light olefins and a heavy hydrocarbon fraction;
separating said light olefins from said heavy hydrocarbon fraction;
contacting said heavy hydrocarbon fraction in a second reactor at conditions
effective to convert at least a portion of said heavy hydrocarbon fraction to light
olefins;
wherein said MeAPO has been prepared by a method comprising :
a) forming a reaction mixture containing a texture influencing agent (TIA),
an organic templating agent (TEMP), at least a reactive inorganic source of
MeO2 essentially insoluble in the TIA, reactive sources of Al2 O3 and P2 O5,
b) crystallizing the above reaction mixture thus formed until crystals of the
metalloaluminophosphate are formed,
c) recovering a solid reaction product,
d) washing it with water to remove the TIA and
e) calcinating it to remove the organic template.
In a usual embodiment said reaction mixture has a composition
expressed in terms of molar oxide ratios of:
TEMP/AI2O3 = 0.3-5 , more desirable 0.5-2
MeO2/Al2O3 = 0.005-2.0, more desirable 0.022-0.8
P2O5/AI2O3 =0.5-2, more desirable 0.8-1.2
TIA/AI2O3 = 3-30, more desirable 6-20
In an advantageous embodiment TEMP/AI2O3 = 0.5-2 ; MeO2/AI2O3 =
0.022-0.8; P2O5/AI2O3 = 0.8-1.2 and TIA/AI2O3 = 6-20.
In a first preferred embodiment TEMP/AI2O3 = 0.5-2 ; MeO2/Al2O3 =
0.022-0.7; P2O5/AI2O3 = 0.8-1.2 and TIA/AI2O3= 6-20.
In a second preferred embodiment TEMP/AI2O3 = 0.7-2 ; MeO2/AI2O3 =
0.05-0.7; P2O5/AI2O3= 0.8-1.2 and TIA/AI2O3= 6-20.
In a third preferred embodiment TEMP/AI2O3 = 0.7-2 ; MeO2/Al2O3 =
0.05-0.6; P2O5/AI2O3= 0.8-1.2 and TIA/AI2O3= 6-20.
The metalloaluminophosphate (MeAPO) molecular sieves made with the
above method have a lamellar crystal morphology.
In a usual embodiment the metalloaluminophosphate (MeAPO)
molecular sieves made with the above method have a lamellar crystal
morphology having an empirical chemical composition on an anhydrous basis,
after synthesis and calcination, expressed by the formula HxMeyAlzPkO2
wherein,
y+z+k=1
x y has a value ranging from 0.0008 to 0.4 and more desirable from 0.005 to 0.18
z has a value ranging from 0.25 to 0.67 and more desirable from 0.38 to 0.55
k has a value ranging from 0.2 to 0.67 and more desirable from 0.36 to 0.54
said molecular sieve having predominantly a plate crystal morphology.
The values of y, z and k in the usual embodiment are obtained by the
ratios of the ingredients described in the usual embodiment method above
described.
In an advantageous embodiment y has a value ranging from 0.005 to
0.18, z has a value ranging from 0.38 to 0.55 and k has a value ranging from
0.36 to 0.54.
In a first preferred embodiment y has a value ranging from 0.005 to 0.16,
z has a value ranging from 0.39 to 0.55 and k has a value ranging from 0.37 to
0.54.
In a second preferred embodiment y has a value ranging from 0.011 to
0.16, z has a value ranging from 0.39 to 0.55 and k has a value ranging from
0.37 to 0.54.
In a third preferred embodiment y has a value ranging from 0.011 to
0.14, z has a value ranging from 0.40 to 0.55 and k has a value ranging from
0.38 to 0.54.
The values of y, z and k in the advantageous, first, second and third
embodiments described above are obtained by using the ingredients ratios
described respectively in the advantageous, first, second and third
embodiments of the method described above.
In an advantageous embodiment the MeAPO made by the above method
have essentially a structure CHA or AEI or a mixture thereof. Preferably they
have essentially the structure SAPO 18 or SAPO 34 or a mixture thereof.
All the conditions already cited above relating to the synthesis of the
MeAPO, the details of the primary reactor, operating conditions of said primary
reactor, the details of the second reactor, operating conditions of said second
reactor etc .. apply to said other embodiment of the invention.
Fig 9 illustrates a specific embodiment of the invention. The effluent of
the primary reactor is passed to a fractionator 11. The overhead, a C1-C3
fraction including the light olefins is sent via line 2 to a common recovery
section (not shown). The bottoms (the heavy hydrocarbon fraction) are sent via
line 3 to the second reactor (OCP reactor). The effluent of the second reactor
(OCP reactor) is sent via line 10 to a fractionator 8. The overhead, a C1-C3
fraction including the light olefins, is sent via line 9 to a common recovery
section (not shown). The bottoms, hydrocarbons having 4 carbon atoms or more,
are sent to a fractionator 5. The overhead, hydrocarbons having 4 to substantially
5 carbon atoms are recycled via line 4 at the inlet of the second reactor. The
bottoms, hydrocarbons having substantially 6 carbon atoms or more, are purged
via line 6.
The method of making the olefin products from an oxygenate feedstock
can include the additional step of making the oxygenate feedstock from
hydrocarbons such as oil, coal, tar sand, shale, biomass and natural gas.
Methods for making oxygenate feedstocks are known in the art. These methods
include fermentation to alcohol or ether, making synthesis gas, then converting
the synthesis gas to alcohol or ether. Synthesis gas can be produced by known
processes such as steam reforming, autothermal reforming and partial
oxidization in case of gas feedstocks or by reforming or gasification using
oxygen and steam in case of solid (coal, organic waste) or liquid feedstocks.
Methanol, methylsulfide and methylhalides can be produced by oxidation of
methane with the help of dioxygen, sulphur or halides in the corresponding
oxygen-containing, halogenide-containing or sulphur-containing organic
compound.
One skilled in the art will also appreciate that the olefin products made by
the oxygenate-to-olefin conversion reaction using the molecular sieve of the
present invention can be polymerized to form polyolefins, particularly
polyethylenes and polypropylenes.
[Examples]
In the following examples :
EG means ethylene glycol,
Eth means ethanol,
MeOH means methanol,
XRD means X ray diffraction,
SEM means scanning electron microscopy,
Aerosil 200® is a fumed silica supplied by Degussa.
Examples 1-3
A reaction mixture of TIA, phosphoric acid (85% in water) and TEAOH
solution (40 % in water) was prepared in a teflon vessel. In this solution were
added corresponding amount of Al source and Si-source respectively. This
slurry was mixed until homogeneous for about 30 min at room temperature.
Then the teflon vessel was put into stainless autoclave. This autoclave was kept
under temperature. After cooling to room temperature, a sample was taken,
washed and dried. Separation of the solid from the liquid phase after synthesis
was performed by centrifugation. Separated solid was dried at 110°C overnight
and calcined in air flow at 600°C for 10h. Proportions and operating conditions
are in the following table. This procedure was applied for the all examples.
Examples 1-3

Examples 4-6
Examples 7-8
Example 9
Synthesis at higher temperature
Examples 10-11
Reduced amount of TIA

Example 12
Synthesis with reduced amount of template

Example 13
Synthesis with increased amount of template in presence of EG

Example 14
Synthesis at lower Si-content

Comparative example I
The essential of this recipe: the source of Si must be soluble in alcohol. In the
present invention all Si sources are not soluble in TIA.
Synthesis of SAPOs in presence of alcohol with organic source of Si according
to US 6 540 970 protocol :

Morphology of the samples synthesized according to this recipe is different from
lamellar. Indeed, a very particular spheroidal morphology has been described in
this patent for SAPO-34 sample. The crystallites have a width, at their largest
dimension, of from about 0.5pm to about 30pm.
Reproduction of example for SAPO-18 synthesis led to materials with cubic
crystals.
Comparative example II
Synthesis of SAPO-18 (Chen's recipe)
- Verified Syntheses of Zeolitic Materials, H. Robson, Elsevier, p.81,
- Catalysis Letters 28 (1994) 241-248
- J. Chem. Soc, Chem. Comm., 1994, 603-604
- J. Phys. Chem. 1994, 98,10216-10224

Comparative example III
Synthesis of SAPOs according to US 6 334 994recipe at high and low Si
content.
Comparative example IV (US 6 953 767 B2)
Inventors in the US 6953767B2 described a synthesis of SAPOs phase
mixed structure. 18/34 phase ratio was tuned by changing the turning rate of
autoclave during the synthesis.
The results showed, that phase composition is reproducible but the
morphology was not lamellar.
Example 15
Catalyst tests were performed on 2g catalyst samples with a pure
methanol feed at 450°C, pressure of 0,5 barg, and WHSV=1.6h-1in a fixed-
bed, down flow stainless-steel reactor. Catalyst powders was pressed into
wafers and crushed to 35-45 mesh particles. Prior to catalytic run all catalysts
were heated in flowing N2 (5 Nl/h) up to the reaction temperature. Analysis of
the products has been performed on-line by a gas chromatograph equipped
with a capillary column. Catalytic performances of MeAPOs molecular sieves
were compared at 100% of methanol conversion and maximum of catalyst
activity just before appearance of DME in the effluent.
The feedstock which contains substantially non cyclic olefins C4+ (the
heavy hydrocarbon fraction) was subjected to catalytic cracking (the second
reactor) in the presence of an aluminosilicate catalyst in a fixed bed reactor at
575°C, LHSV=10h-1, P=1,5 bara. This catalyst comprises a commercially
available silicalite which had been subjected to a dealumination treatment by
combination of steaming with acid treatment so as provide Si/AI ratio -250. A
detailed procedure of catalyst preparation is described in above cited
EP1194502 B1.
The OCP performance has been simulated using a mathematic model
employing conversion factors deduced from numerous testing of different
feedstocks. Based on the stream composition going to the OCP reactor and on
the required purges an optimum stream of C4 and heaviers are recycled around
the OCP reactor. The lines under "OCP feed non cyclic olefins C4+" display the
heavy hydrocarbon flow rate sent to the OCP (the second reactor). The lines
under "MTO+OCP" display the ethylene and propylene produced by the
combination of the primary reactor (MTO) and the second reactor (OCP).
The results are in table 1 hereunder. The values in table 1 are the weight
percent on carbon basis.
Example 16
Catalyst tests were performed on 2g catalyst samples with a
methanol/H2O: 70/30 feed at 450°C,pressure of 0,2 barg, WHSV=2.9 h-1, in a
fixed-bed, down flow stainless-steel reactor. Catalyst powders was pressed into
wafers and crushed to 35-45 mesh particles. Prior to catalytic run all catalysts
were heated in flowing N2 (5 Nl/h) up to the reaction temperature. Analysis of
the products has been performed on-line by a gas chromatograph equipped
with a capillary column. Catalytic performances of SAPOs molecular sieves
were compared at 100% of methanol conversion and maximum of catalyst
activity just before appearance of DME in the effluent.
The feedstock which contains C4 and C5 olefins (the heavy hydrocarbon
fraction) was subjected to catalytic cracking (the second reactor) in the
presence of an aluminosilicate catalyst in a fixed bed pilot plant at 575°C,
LHSV=10h-1, P=1,5 bara. This catalyst comprises a commercially available
silicalite which had been subjected to a dealumination treatment by combination
of steaming with acid treatment so as provide Si/AI ratio -250. A detailed
procedure of catalyst preparation is described in above cited EP1194502 B1.
The OCP performance has been simulated using a mathematic model
employing conversion factors deduced from numerous testing of different
feedstocks. Based on the stream composition going to the OCP reactor and on
the required purges an optimum stream of C4 and heaviers are recycled around
the OCP reactor. The lines under "OCP feed non cyclic olefins C4+" display the
heavy hydrocarbon flow rate sent to the OCP (the second reactor). The lines
under "MTO+OCP" display the ethylene and propylene produced by the
combination of the primary reactor (MTO) and the second reactor (OCP).
The results are in table 1 hereunder. The values in table 2 are the weight
percent on carbon basis.
CLAIMS
1 Process to make light olefins from an oxygen-containing,
halogenide-containing or sulphur-containing organic feedstock comprising :
contacting said oxygen-containing, halogenide-containing or sulphur-containing
organic feedstock in a primary reactor with a catalyst made of a
metalloaluminophosphate (MeAPO) molecular sieve with lamellar crystal
morphology at conditions effective to convert at least a portion of the feedstock
to form a first reactor effluent comprising light olefins and a heavy hydrocarbon
fraction;
separating said light olefins from said heavy hydrocarbon fraction;
contacting said heavy hydrocarbon fraction in a second reactor at conditions
effective to convert at least a portion of said heavy hydrocarbon fraction to light
olefins;
wherein said MeAPO has an empirical chemical composition on an anhydrous
basis, after synthesis and calcination, expressed by the formula HxMeyAlzPk02
in which,
y+z+k=1
x y has a value ranging from 0.0008 to 0.4
z has a value ranging from 0.25 to 0.67
k has a value ranging from 0.2 to 0.67
said molecular sieve having predominantly a plate crystal morphology in
which the width (W) and the thickness (T) are such as :
V/T is>=10.
2 Process according to claim 1 wherein y has a value from 0.005 to
0.18.
3 Process according to any one of the preceding claims wherein z
has a value from 0.38 to 0.55.
4 Process according to any one of the preceding claims wherein k
has a value from 0.36 to 0.54.
5 Process according to any one of the preceding wherein y has a
value ranging from 0.005 to 0.18, z has a value ranging from from 0.38 to 0.55
and k has a value ranging from 0.36 to 0.54.
6 Process according to claim 5 wherein y has a value ranging from
0.005 to 0.16, z has a value ranging from from 0.39 to 0.55 and k has a value
ranging from 0.37 to 0.54.
7 Process according to claim 6 wherein y has a value ranging from
0.011 to 0.16, z has a value ranging from from 0.39 to 0.55 and k has a value
ranging from 0.37 to 0.54.
8 Process according to claim 7 wherein y has a value ranging from
0.011 to 0.14, z has a value ranging from from 0.40 to 0.55 and k has a value
ranging from 0.38 to 0.54.
9 Process according to any one of the preceding claims wherein Me
is silicon.
10 Process according to any one of the preceding claims wherein T is
11 Process according to claim 10 wherein T is 12 Process according to claim 11 wherein T is 13 Process according to claim 12 wherein T ranges from 0.01 to 0.07
µm.
14 Process according to claim 13 wherein T ranges from 0.01 to 0.04
urn.
15 Process according to any one of the preceding claims wherein
W/T ranges from 10 to 100.
16 Process according to any one of the preceding claims wherein the
structure is essentially CHA or AEI or a mixture thereof.
17 Process according to any one of the preceding claims wherein the
structure is essentially SAPO 18 or SAPO 34 or a mixture thereof.
18 Process to make light olefins from an oxygen-containing,
halogenide-containing or sulphur-containing organic feedstock comprising :
contacting said oxygen-containing, halogenide-containing or sulphur-containing
organic feedstock in a primary reactor with a catalyst made of a
metalloaluminophosphate (MeAPO) molecular sieve at conditions effective to
convert at least a portion of the feedstock to form a first reactor effluent
comprising light olefins and a heavy hydrocarbon fraction;
separating said light olefins from said heavy hydrocarbon fraction;
contacting said heavy hydrocarbon fraction in a second reactor at conditions
effective to convert at least a portion of said heavy hydrocarbon fraction to light
olefins;
wherein said MeAPO has been prepared by a method comprising :
a) forming a reaction mixture containing a texture influencing agent (TIA),
an organic templating agent (TEMP), at least a reactive inorganic source of
MeO2 essentially insoluble in the TIA, reactive sources of Al2 O3 and P2 O5,
b) crystallizing the above reaction mixture thus formed until crystals of the
metalloaluminophosphate are formed,
c) recovering a solid reaction product,
d) washing it with water to remove the TIA and
e) calcinating it to remove the organic template.
19 Process according to claim 18 wherein said reaction mixture has a
composition expressed in terms of molar oxide ratios of:
TEMP/AI2O3 = 0.3-5 ,
MeO2/Al2O3 = 0.005-2.0,
P2O5/AI2O3= 0.5-2,
TIA/AI2O3=3-30.
20 Process according to any one of claims 18 to 19 wherein the ratio
TEMP/AWa =0.5-2.
21 Process according to any one of claims 18 to 20 wherein the ratio
MeO2/Al2O3 =0.022-0.8.
22 Process according to any one of claims 18 to 21 wherein the ratio
P2O5/AI2O3=0.8-1.2.
23 Process according to any one of claims 18 to 22 wherein the ratio
TIA/AI2O3=6-20.
24 Process according to claim 18 wherein TEMP/AI2O3 = 0.5-2 ;
MeO2/Al2O3 = 0.022-0.8; P2O5/Al2O3 = 0.8-1.2 and TIA/Al2O3 = 6-20.
25 Process according to claim 24 wherein TEMP/AI2O3 = 0.5-2 ;
MeO2/Al2O3 = 0.022-0.7; P2O5/AI2O3 = 0.8-1.2 and TIA/Al2O3 = 6-20.
26 Process according to claim 25 wherein TEMP/AI2O3 = 0.7-2 ;
MeO2/Al2O3 = 0.05-0.7; P2O5/AI2O3= 0.8-1.2 and TIA/AI2O3= 6-20.
27 Process according to claim 26 wherein TEMP/AI2O3 = 0.7-2 ;
MeO2/Al2O3 = 0.05-0.6; P2O5/AI2O3= 0.8-1.2 and TIA/AI2O3= 6-20.
28 Process according to any one of claims 18 to 27 wherein Me is
silicon.
29 Process according to any one of claims 18 to 28 wherein the
texture influencing agent (TIA) is selected among 1,2-propanediol, 1,3-
propanediol, methanol, ethanol, propanol, isopropanol, butanol, glycerol or
ethylene glycol.
30 Process according to any one of claims 18 to 29 wherein the
structure is essentially CHA or AEI or a mixture thereof.
31 Process according to any one of claims 18 to 30 wherein the
structure is essentially SAPO 18 or SAPO 34 or a mixture thereof.
32 Process according to any one of the preceding claims wherein the
oxygenate (oxygen containing) compounds are methanol, dimethyl ether, or a
mixture thereof.
33 Process according to any one of the preceding claims wherein the
catalyst of the second reactor comprises a crystalline silicate of the MFI family
or the MEL family.
34 Process according to claim 33 wherein the catalyst is a ZSM-5 or
a silicalite.
35 Process according to any one of the preceding claims wherein
ethylene, in whole or in part, coming either from effluent of the first reactor
either from effluent of the second reactor is recycled back to the inlet of the first
reactor.
36 Process according to any one of the preceding claims wherein
ethylene, in whole or in part, coming either from effluent of the first reactor
either from effluent of the second reactor is recycled back to the inlet of the
second reactor.
37 Process according to any one of the preceding claims wherein
effluent of the second reactor is sent to a fractionnator to separate (i) light
olefins from (ii) hydrocarbons having 4 carbon atoms or more;
said hydrocarbons having 4 carbon atoms or more are recycled at the inlet of
the second reactor.
38 Process according to any one of the preceding claims wherein
ethylene is further polymerized optionally with one or more comonomers.
39 Process according to any one of the preceding claims wherein
propylene is further polymerized optionally with one or more
comonomers.



The present invention relates to a process to make light olefins from an oxygen-containing, halogenide-containing or
sulphur-containing organic feedstock comprising: contacting said oxygen-containing, halogenide-containing or sulphur-containing
organic feedstock in a primary reactor with a catalyst made of a metalloaluminophosphate (MeAPO) molecular sieve with lamellar
crystal morphology at conditions effective to convert at least a portion of the feedstock to form a first reactor effluent comprising
light olefins and a heavy hydrocarbon fraction; separating said light olefins from said heavy hydrocarbon fraction; contacting said
heavy hydrocarbon fraction in a second reactor at conditions effective to convert at least a portion of said heavy hydrocarbon fraction
to light olefins; wherein said MeAPO has an empirical chemical composition on an anhydrous basis, after synthesis and calcination,
expressed by the formula HxMeyAlzPkO2 in which, y+z+k=l x 0.005 to 0.18 z has a value ranging from 0.25 to 0.67 and advantageously from 0.38 to 0.55 k has a value ranging from 0.2 to 0.67
and advantageously from 0.36 to 0.54 said molecular sieve having predominantly a plate crystal morphology in which the width (W)
and the thickness (T) are such as: W/T is >= 10 and advantageously ranges from 10 to 100.

Documents:

3499-KOLNP-2009-(11-07-2013)-ABSTRACT.pdf

3499-KOLNP-2009-(11-07-2013)-CLAIMS.pdf

3499-KOLNP-2009-(11-07-2013)-CORRESPONDENCE.pdf

3499-KOLNP-2009-(11-07-2013)-FORM-2.pdf

3499-KOLNP-2009-(11-07-2013)-FORM-3.pdf

3499-KOLNP-2009-(11-07-2013)-OTHERS.pdf

3499-KOLNP-2009-(11-07-2013)-PETITION UNDER RULE 137.pdf

3499-kolnp-2009-abstract.pdf

3499-KOLNP-2009-ASSIGNMENT-1.1.pdf

3499-KOLNP-2009-ASSIGNMENT.pdf

3499-KOLNP-2009-CANCELLED PAGES.pdf

3499-kolnp-2009-claims.pdf

3499-KOLNP-2009-CORRESPONDENCE 1.1.pdf

3499-kolnp-2009-correspondence.pdf

3499-kolnp-2009-description (complete).pdf

3499-kolnp-2009-drawings.pdf

3499-KOLNP-2009-EXAMINATION REPORT.pdf

3499-kolnp-2009-form 1.pdf

3499-KOLNP-2009-FORM 18-1.1.pdf

3499-KOLNP-2009-FORM 18.pdf

3499-kolnp-2009-form 3.pdf

3499-kolnp-2009-form 5.pdf

3499-KOLNP-2009-GPA-1.1.pdf

3499-kolnp-2009-gpa.pdf

3499-KOLNP-2009-GRANTED-ABSTRACT.pdf

3499-KOLNP-2009-GRANTED-CLAIMS.pdf

3499-KOLNP-2009-GRANTED-DESCRIPTION (COMPLETE).pdf

3499-KOLNP-2009-GRANTED-DRAWINGS.pdf

3499-KOLNP-2009-GRANTED-FORM 1.pdf

3499-KOLNP-2009-GRANTED-FORM 2.pdf

3499-KOLNP-2009-GRANTED-FORM 3.pdf

3499-KOLNP-2009-GRANTED-FORM 5.pdf

3499-KOLNP-2009-GRANTED-LETTER PATENT.pdf

3499-KOLNP-2009-GRANTED-SPECIFICATION-COMPLETE.pdf

3499-KOLNP-2009-INTERNATIONAL PUBLICATION-1.1.pdf

3499-kolnp-2009-international publication.pdf

3499-KOLNP-2009-INTERNATIONAL SEARCH REPORT & OTHERS.pdf

3499-KOLNP-2009-OTHERS.pdf

3499-kolnp-2009-pct priority document notification.pdf

3499-kolnp-2009-pct request form.pdf

3499-KOLNP-2009-PETITION UNDER RULE 137.pdf

3499-KOLNP-2009-REPLY TO EXAMINATION REPORT.pdf

3499-kolnp-2009-specification.pdf

abstract-3499-kolnp-2009.jpg


Patent Number 263376
Indian Patent Application Number 3499/KOLNP/2009
PG Journal Number 44/2014
Publication Date 31-Oct-2014
Grant Date 24-Oct-2014
Date of Filing 08-Oct-2009
Name of Patentee TOTAL PETROCHEMICALS RESEARCH FELUY
Applicant Address ZONE INDUSTRIELLE C, B-7181 SENEFFE (FELUY) BELGIUM
Inventors:
# Inventor's Name Inventor's Address
1 NESTERENKO, NIKOLAI BOÎTE 21, BÂT. 32, CHAUSSÉE DE NAMUR, B-1400 NIVELLES, BELGIUM
2 VERMEIREN, WALTER WINNINGSTRAAT, 4, B-3530 HOUTHALEN BELGIUM
PCT International Classification Number C07C1/20; C07C4/06; C07C11/04;
PCT International Application Number PCT/EP2008/052816
PCT International Filing date 2008-03-10
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 07104063.8 2007-03-13 EUROPEAN UNION
2 60/919,729 2007-03-23 EUROPEAN UNION