Title of Invention

" AN IMPROVED PROCESS FOR THE PREPARATION OF VINYLPYRIDINE FROM CORRESPONDING PICOLINE OVER MODIFIED ZEOLITE CATALYST IN VAPOUR PHASE"

Abstract The present invention relates to a process for the preparation of 2-vinylpyridien from corresponding picoline over modified zeolite catalysts in vapour phase. In particular, it relates to a method for the synthesis of vinylpyridine from corresponding picoline with formaldehyde in vapour phase in an eco-friendly method with high yield and selectivity. The process is a non-corrosive, eco-friendly, where the catalyst can be recycled and reused for many times. 2-Vinylpyridien and 4-vinylpyridine are useful starting material in polymer industry. The process steps are: reacting picoline with formaldehyde with a molar ratio of formaldehyde to picoline in the range of 1:1 to 4:1, at a temperature ranging between 200 to 450°C, at a weight hourly space velocity in the range of 0.25 hr-1 - 1.00 hr-1 over a modified commercial zeolite catalyst, to obtain the desired product.
Full Text The present invention relates to a process for the preparation of 2-vinylpyridien from corresponding picoline over modified zeolite catalysts in vapour phase. In particular, it relates to a method for the synthesis of vinylpyridine from corresponding picoline with formaldehyde in vapour phase in an eco-friendly method with high yield and selectivity.
This invention provides a non-corrosive, eco-friendly process, where the catalyst can be recycled and reused for many times. 2-Vinylpyridien and 4-vinylpyridine are useful starting material in polymer industry.
2-Vinylpyridine (2-VP) is an important monomer used in synthesizing various polymers. Butadiene and styrene monomers were used with 2-vinylpyridine to form latex terpolymer that bonded fabric cordis to the rubber matrix of tires. The addition product of methanol and 2-vinylpyridine, 2-(2-methoxy-ethyl) pyridine is a veterinary anthelmintic. This monomer is prepared commercially by autoclaving acetylene, acrylonitrile using cobaltocene catalyst or oxidative dehydrogenation of 2-ethylpyridine on Cr-Nb catalyst (Y. Wakatasuki, synthesis, 1, 26 (1976). ("Heterocyclic compounds: Pyridine and Pyridine derivatives part 2, Ed. E.Kliggsberg, Chapt. V, P 203). Generally in most of the processes, the synthesis of 2-vinylpyridine is practiced by a two - step procedure, which involves a base catalyzed addition or 2-picoline to formaldehyde to give 2-(2-hydroxy ethyl) pyridine followed by dehydration to 2-vinylpyridine monomer. (S. Yasuda, H. Niwa and O.Tagano, Jpn. Kokai Tokyo, Koho 78, 141281 (1978). 2-Vinylpyridine was prepared with 70.8% selectivity at 35.8% conversion over ZrO2 catalyst (Reddy B.N. and Subrahymanyam M, Catalysis Present & Future, Eds. Kanta Rao P.&Beniwal R.S.p. 304(1995). The synthesis of vinylpyridines are also reported by the dehydrogenation of

alkyl pyridines over ViOs/MgO and MoCVMgO catalysts in the presence of 62. The
alkylation of pyridine, 2,3, and 4-picolines with methanol as alkylating agent over alkali
metal ion exchanged X and Y type zeolites in Na atmosphere resulted in the formation of
side-chain alkylated products like ethylpyridines and vinylpyridines were 22.2, and 5.3%
at 82.0% conversion over CsY catalyst from 2-picoline and methanol at 450°C. However
considerable amounts of ring-alkylated derivatives (lutidines) were formed
simultaneously. (Kshiwagi H., Enomoto S., Chem. Pharm. Bull, 30(2), 404(1982)).
The alkylation of picolines with methanol was studied over modified X and Y zeolites in
which the major products were ethylpyridine and vinylpyridine (Chem. Pharm. Bull.,
30(2), 404, 1982). The yields of ethylpyridine were more when the CsY zeolite was used
at 450°C. On the other hand the yields of vinylpyridines were more over CsX zeolite at
about 425°C. The yields of vinylpyridines were vinylpyridines were also reported by the dehydrogenation of alkylpyridines over
V2O5/MgO and MoOs/MgO catalysts in the presence of oxygen. However the yields and
selectivities of 4-vinylpyridine were lower
The main objective of the present invention is to provide a process for the
synthesis of vinylpyridines over modified zeolites in a heterogeneous eco-friendly
method.
Another objective of the present invention is to provide a process for the
preparation of 2-vinylpyridine in high yield and high selectivity.
Another object of the present invention is to provide a process for the preparation
of 4-vinylpyridine in high yield and high selectivity.
Another object of the present invention is to provide a process for the preparation
of 2-vinylpyridine from 2-picoline and formaldehyde in the presence of catalyst which
comprises ZSM-5 containing one or two element(s) from alkali and/or alkaline earth
metal ions, like Na+, K+, Rb+, Cs+, Mg+2, Ca+2, Sr+2, etc., which can be recycled and
reused for several times.
Still another object of the present invention is to provide a process for the
preparation of 4-vinylpyridine from 4-picoline and formaldehyde in the presence of a
catalyst which comprises ZSM-5 containing one or two element(s) from alkali and
alkaline earth metal ions, like Na, K, Rb, Cs, Mg, Ca, Sr, Ba etc., which can be recycled
and reused for several times.
The present invention provides a process for the preparation of 2-vinylpyridine
from 2-picoline and formaldehyde in vapour phase over 2-picoline and formaldehyde in
vapour phase over zeolite / molecular sieve. The catalyst comprises of particularly ZSM-
5 (pentasil family) with or without sodium, potassium, rubidium, cesium, magnesium,
calcium, and/or barium, etc cation or species.
The present invention also provides a process for the preparation of 4-
vinylpyrdine from 4-picoline and formaldehyde in vapour phase over zeolite molecular
sieve. The catalyst comprises of ZSM-5 with or with out sodium, potassium, rubidium,
cesium, magnesium, calcium or barium. Accordingly the present invention provides an improved process for the preparation of vinyl pyridine from corresponding picoline over modified zeolite catalyst in vapour phase which comprises; reacting picoline with formaldehyde with a molar ratio of formaldehyde to picoline in the range of 1:1 to 4:1, at a temperature ranging between 200 to 450°C, at a weight hourly space velocity in the range of 0.25 hr-1 - 1.00 hr-1 characterized in that over a modified commercial zeolite catalyst, the said catalyst is selected from the group consisting of ZSM-5, X, Y, mordenite and MCM-41 and modified with one or two element(s) from alkali and alkaline earth metal ions to obtain the desired product.
In an another embodiment the vinyl pyridine used is selected from 2-vinylpyridien and 4-vinylpyridine.
In yet another embodiment one of the reactant picoline used is selected from 2-picoline and 4-picoline.
In yet another embodiment the catalyst used is a modified zeolite prepared by varying alkali and alkaline earth selected from the group consisting of ZSM-5, X, Y, mordienlite and MCM-41.
In yet another embodiment the modification of the catalyst, preferably ZSM-5 (pentasil type zeolite) is carried out by alkali or alkaline earth metal ion selected from the group consisting of Li+, Na+, K+, Rb+, Cs+, Mg+2, Ca+2, Sr+2, Ba+2 or two cation modified ZSM-5 like Cs-K-ZSM-5.
In yet another embodiment the weight percent of the alkali or alkaline earth metal cation in ZSM-5 catalyst used is in the range of 1 to 4 wt%.
In yet another embodiment the precursor used to modify ZSM-5 catalyst by potassium ion or other elements selected from the group consisting of KO,Bu, KOH, KF, KNO3, K3PO4 and KOAc to improve the yield and selectivity of vinyl pyridine.
In yet another embodiment wherein the calcination temperature of modified
zeolite used is varied from 400°C to 700°C.
In yet another embodiment the reaction temperature of the catalytic zone used is
varied from 200°C to 450°C.
In still another embodiment the weight hourly space velocity (WHSV) used is
preferably in the range of 0.25 to 1.0 hr"1.
The following catalysts were used in the present process development HZSM-5
(SiO2/Al2O3 = 30), NaY (Si02/Al2O3= 5.0), H-Mordenite (SiO2/Al2O3= 12), and HMCM-
41 (SiO2/Al2O3= 31). Each zeolite was pelleted without binder, crushed and sized
18-30 mesh before the impregnation. The catalysts were modified by using required
amount of alkali or alkaline earth cation nitrate by an impregnation method. In the case of
potassium, different precursors like KOlBu, KF, KOAc, K3PC>4 and KOH were used to
modify ZSM-5 (30) catalyst. The required amount of precursor was taken in the form of
nitrate or other soluble salts in 30 ml of distilled water. 4.0 g of the meshed catalyst was
added to it and kept for soaking for 12 h. Then it was dried at 110°C overnight and
calcined at 420°C for 4 h before using for the reaction. In a typical procedure for the
synthesis of KOlBu modified ZSM-5 (30) catalyst is as follows, 7 g of HZSM-5 (30) was
taken in 250 ml two-necked round bottom flask. Prior to the modification the catalyst was
predried in oven at 100°C for 1 h followed by flushing with nitrogen gas to remove the
water present in the channels of the catalyst. In another round bottom flask required
amount of KOlBu was dissolved in dry DMSO solvent. This solution was added to
HZSM-5 (30) catalyst and kept stirring for 24 h in presence of nitrogen atmosphere. After
24 h stirring the resultant mixture was filtered, dried at 120°C overnight and calcined at
400°C for 4 h. The reactions were carried out in a fixed bed, continuous, down-flow
pyrex reactor with 20 mm internal diameter at atmospheric pressure. All the catalysts
were activated by calcination in a flow of air at 420°C for 4 h and brought to the reaction
temperature in situ. The catalyst temperature was measured with a thermocouple placed
in the middle of the catalyst bed. A mixture of 2-picoline and formaldehyde were fed
from a syringe pump at a rate of 2 ml.h"1. The products from the reactor was cooled by
circulating ice-cooled water and periodically collected. The quantitative analysis of
product was carried out by gas chromatography (G.C.). The samples were analyzed by
G.C. (Schimadzu-17A and 14B) fixed with an OV-17 (2mmXl/8"OD) on chromosorb
W-HP column and flame ionization detector. The retention times were compared with the
authentic compounds. The products were confirmed by mass spectra, GC-mass and NMR
techniques. The mass balance was >90-95%.
The following catalysts were used in the present process development HZSM-5
(Si02/Al2O3= 30), NaY (SiO2/Al2O3= 5.0), H-Mordenite (SiO2/Al2O3= 12), and H-MCM-
41 (Si02/Al2O3= 31). Each zeolite was pelleted without binder, crushed and sized 18-30
mesh before the impregnation. The catalysts were modified by using required amount of
alkali or alkaline earth cation nitrate by an impregnation method. In the case of
potassium, different precursors like KOlBu, KF, KOAc, KsPC^ and KOH were used to
modify ZSM-5 (30) catalyst. The required amount of precursor was taken in the form of
nitrate or other soluble salts in 30 ml of distilled water. 4.0 g of the meshed catalyst was
added to it and kept for soaking for 12 h. Then it was dried at 110°C overnight and
calcined at 420°C for 4 h before using for the reaction. In a typical procedure for the
synthesis of KOlBu modified ZSM-5 (30) catalyst is as follows, 7 g of HZSM-5 (30) was
taken in 250 ml two-necked round bottom flask. Prior to the modification the catalyst was
predried in oven at 100°C for 1 h followed by flushing with nitrogen gas to remove the
water present in the channels of the catalyst. In another round bottom flask required
amount of KOlBu was dissolved in dry DMSO solvent. This solution was added to
HZSM-5 (30) catalyst and kept stirring for 24 h in presence of nitrogen atmosphere. After
24 h stirring the resultant mixture was filtered, dried at 120°C overnight and calcined at
400°C for 4 h. The reactions were carried out in a fixed bed, continuous down-flow pyrex
reactor with 20 mm internal diameter at atmospheric pressure. All the catalysts was
activated by calcination in a flow of air at 420°C for 4 h and brought to the reaction
temperature in situ. The catalyst temperature was measured with a thermocouple placed
in the middle of the catalyst bed. A mixture of 4-picoline and formaldehyde were fed
from a syringe pump at a rate of 2 ml.h"1. The products from the reactor was cooled by
circulating ice-cooled water and periodically collected. The quantitative analysis of
product was carried out by gas chromatography (G.C.). The samples were analyzed by
G.C. (Schimadzu-17A and 14B) fixed with an OV-17 (2mmXl/8"OD) on chromosorb
W-HP column and flame ionization detector. The retention times were compared with the
authentic compounds. The products were confirmed by mass spectra, GC-mass and NMR
techniques. The mass balance was >90-95%.
EXAMPLES
The present invention will be explained in more detail by the following examples,
which do not limit the scope of the invention in any way.
EXAMPLE-1:
Synthesis of potassium modified ZSM-5.
Four grams of calcined HZSM-5 having SiCVAhOs molar ratio of 30 was taken
in the form of 18-30 mesh size and soaked in 30 ml of the solution of potassium nitrate
containing 0.4 g potassium (K) for 12 h. Then it was dried at 110°C overnight and
calcined at ~420°C for 4 h before using for the reaction.
EXAMPLE-2:
Synthesis of cesium modified ZSM-5
The same procedure as given in Example-1 was used for the preparation of
other metal ion ZSM-5 catalyst by using their inorganic salts as precursors. Cesium
nitrate was used for Cs-ZSM-5.
EXAMPLE-3:
The modified ZSM-5 was used in the following reaction for the preparation of 2-
vinylpyridine.
Cs-ZSM-5 (SiCVA^Os = 30) catalyst was packed in a pyrex reactor having an
inner diameter of 20 mm with the length of 30-40 cms and the catalytic zone was heated
at 300°C. Then a mixture of 2-picoline and formaldehyde in a molar ratio of 1:2 was fed
from the top of the reactor at a weight hourly space velocity of o.5 h"1. The liquid product
selectivity of 2-vinylpyridine was 92.8% at 40.4% conversion of 2-picoline at 4th hour on
stream. The conversion of 2-picoline was in the range of 4- >10% with 30 -81.5%
selectivity of 2-picoline at 300°C over CsY, Cs-mordenite and Cs-MCM-41.
EXAMPLE 4:
The reaction of 2-picoline and formaldehyde was carried out over K-ZSM-5
(SiO2/Al2O3 = 30) at 300°C with 0.5 h"1 weight hourly space velocity (W.H.S.V). The
catalyst was 4 g with 18-30 mesh size and feed rate was 2 ml.hr"1. 2-Picoline to
formaldehyde was 1:2 molar. The liquid product selectivity of 2-vinylpyridine was 81.1%
at 65.7% conversion of 2-picoline. 2-Ethylpyridine and other products were less than
18.9% selectivity. The reactor design and the other experimental details were as
explained in Example-3 and the text.
EXAMPLE-5:
The reaction of 2-picoline and formaldehyde was carried out over Rb-ZSM-5
(SiO2/Al2O3 = 30) at 300°C with 0.5 h'1 W.H.S.V. The experimental conditions are as
explained in Example-3. The weight of the rubidium was 3 wt% in ZSM-5 catalyst. The
percent liquid product selectivity of 2-vinylpyridine was 86.1% at 61.0% conversion of 2-
picoline. The conversion of formaldehyde was -100%.
EXAMPLE-6:
The reaction of 2-picoline and formaldehyde was carried out over Na-ZSM-5
(SiO2/Al2O3 = 30) at 300°C and 0.5 h"1 W.H.S.V. The experimental conditions are as
explained in Example-3. The weight of sodium was 3 wt% in ZSM-5 catalyst. The liquid
product selectivity of 2-vinylpyridine was 99.7% at 35.0% conversion of 2-picoline
during 4th hour on stream.
EXAMPLE-7:
The reaction of 2-picoline and formaldehyde was carried out over CaZSM-5
(SiO2/Al2O3 = 30) at 300°C and 0.5 h'1 W.H.S.V. The experimental conditions are as
explained in Example-3. The weight of calcium was 3 wt% in ZSM-5 catalyst. The liquid
product selectivity of 2-vinylpyridine was 72.2% at 57.2% conversion of 2-picoline
during 4th hour on stream. Mg-ZSM-5, Sr-ZSM-5 and Ba-ZSM-5 were also tested with
lower yields.
EXAMPLE-8:
The ZSM-5 was modified using two cations like potassium (K) and cesium (Cs).
The reaction of 2-picoline and formaldehyde was carried out over Cs-K-ZSM-5 (1 wt%
Cs & 3 wt% K) at 300°C and 0.5 h"1 W.H.S.V. The experimental conditions were as
given in Example-3. The liquid product selectivity of 2-vinylpyridine was 96.4% at
47.8% conversion of 2-picoline during 4th hour on stream.
EXAMPLE-9:
The liquid product selectivities of 2-vinylpyridine were 96.2, 99.7, 99.8, 81.1,
98.9 and 99 % at 82.4, 72.7, 54.3, 65.7, 56.8, and 61.8 % conversions of 2-picoline
when KOlBu, KOH, KF, KNOa, KsPCU and KOAc were used as precursors or as a
potassium-source to prepare K-ZSM-5 (3 wt% K, SiCVA^Os = 30), respectively. The
experimental conditions were as given in Example-3.
EXAMPLE-10:
The liquid product selectivities of 2-vinylpyridine were 93.3, 87.6, 81.1, and
80.7% at 49.1, 49.9, 65.7, and 66.4% conversions of 2-picoline over lwt% K-ZSM-5
(SiO2/Al2O3 = 30), 2 wt% K-ZSM-5 (30), 3 wt% K-ZSM-5 (30) and 4 wt% K-ZSM-5
(30) catalysts, respectively. The experimental conditions were as given in Example-3.
Similarly the weight percent of cesium (Cs) was varied and conversions and selectivities
were studied. The activity for Cs-ZSM-5 was lower than that for K-ZSM-5 catalysts.
EXAMPLE-11:
The liquid product selectivities of 2-vinylpyridine were 88.1, 57.6, 92.8, 75.9 and
84.4% at 19.4, 28.3, 40.4, 61.5, and 37.8% conversions of 2-picoline at 200, 250, 300,
350, and 400°C reaction temperatures over 3wt% Cs-ZSM-5 (SiO2/Al2O3 = 30)
respectively. The other experimental conditions were as given in Example-3.
EXAMPLE-12:
The liquid product selectivities of 2-vinylpyridine were 73.6, 92.1, 74.6, and
74.0% at 60.3, 40.7, 63.9, and 62.7% conversions of 2-picoline with 1:1, 1:2, 1:3, and 1:4
molar ratio of 2-picoline/formaldehyde respectively. The catalyst was 3 wt% Cs-ZSM-5
(SiO2/Al2O3 = 30). The other experimental conditions were as given in Example-3.
EXAMPLE-13:
The liquid product selectivities of 2-vinylpyridine were 90.5, 92.1, 73.0, and
75.5% at 40.9, 40.7, 54.9, and 57.1% conversions of 2-picoline at 0.25, 0.5, 0.75, and 1.0
h"1 weight hourly space velocities (at 4th hour on stream) respectively. The catalyst was 3
wt% Cs-ZSM-5 (SiO2/Al2O3 = 30) and formaldehyde /2-picoline is 2 molar. The reaction
temperature was 300°C. The other experimental conditions were as given in Example-3.
EXAMPLE-14:
With the experimental details as given in Example-3; the time on stream was
studied and steady states activity and yields were obtained for > 8 hours on stream.
EXAMPLE 15:
The modified ZSM-5 was used in the following reaction for the preparation of 4-
vinylpyridine.
Cs-ZSM-5 (SiO2/Al2O3= 30) catalyst was packed in a pyrex reactor having an
inner diameter of 20 mm with length 30-40 mm and the catalyst-packed part of the tube
(catalytic zone) was heated to 300°C. Then a mixture of 4-picoline and formaldehyde in a
molar ratio of 1:2 was fed from top of the reactor at a weight hourly space velocity of 0.5
hr.sup.-l. The liquid product selectivity of 4-vinylpyridine was 96.8% at 49.3%
conversion of 4-picoline at 4th hour on stream. The conversion of 4-picoline was in the
range of 20-45% with 40-62% selectivity of 4-vinylpyridine at 300°C over CsY, Csmordenite
and Cs-MCM-41.
EXAMPLE 16:
The reaction of 4-picoline and formaldehyde was carried out over K-ZSM-5
(SiO2/Al2O3= 30) at 300°C with 0.5 h"1 weight hourly space velocity (W.H.S.V). The
catalyst was 4 g with 18-30 mesh size and feed rate was 2 ml.h"1. 4-picoline to
formaldehyde was 1:2 molar. The liquid product selectivity of 4-vinylpyridine was 97.0%
at 77.6% of the conversion of 4-picoline. 4-Ethylpyridine and other products were less
than 3% selectivity. The reactor design and the other experimental details were as
explained in Example-15 and the text.
EXAMPLE 17:
The reaction of 4-picoline and formaldehyde was carried out over Rb-ZSM-5
(SiO2/Al203= 30) at 300°C with 0.5 h"1 W.H.S.V. The experimental conditions are as
explained in Example-15. The weight of the rubidium was 3 wt% in ZSM-5 catalyst. The
percent liquid product selectivity of 4-vinylpyridine was 96.2% at 85.2% conversion of 4-
picoline. The formaldehyde conversion was 100%.
EXAMPLE 18:
The reaction of 4-picoline and formaldehyde was carried out over Na-ZSM-5
(SiO2/Al2O3= 30) at 300°C and 0.5 h"1 W.H.S.V. The experimental conditions are as
explained in Example-15. The weight of sodium (Na) was 3wt% in ZSM-5 catalyst. The
liquid product selectivity of 4-vinylpyridine was 99.3% at 76.9% conversion of 4-
picoline during 4th hour on stream.
EXAMPLE 19:
The reaction of 4-picoline and formaldehyde was carried out over Ca-ZSM-5
(SiO2/Al2O3= 30) at 300°C and 0.5h': W.H.S.V. The experimental conditions are as
explained in Example-15. The weight of calcium was 3wt% in ZSM-5 catalyst. The
liquid product selectivity of 4-vinylpyridine was 83.9% at 37.2% conversion of 4-
picoline during 4th hour on stream. Mg-ZSM-5, Sr-ZSM-5 and Ba-ZSM-5 were also
tested with lower yield.
EXAMPLE 20:
The ZSM-5 was modified using two cations like K and Cs. The reaction of 4-
picoline and formaldehyde was carried out over Cs-K-ZSM-5 (lwt%Cs & 3wt% K) at
300°C and 0.5 h"1 W.H.S.V. The experimental conditions were as given in Example-15.
The liquid product selectivity of 4-vinylpyridine was 96.1% at 69.8% conversion of 4-
picoline during 4th hour on stream.
Example 21:
The liquid product selectivities of 4-vinylpyridine were 78.2, 99.3, 96.8, 97.3, and
95.3% at 80.2, 85.1, 91.9, 90.0, and 91.5% conversion of 4-picoline when KO'Bu, KOH,
KF, KsPO4 and KOAc were used as precursors or as a potassium- source to prepare KZSM-
5 (3wt% K, SiO2/Al203= 30), respectively. The experimental conditions were as
given in Example-15.
EXAMPLE 22:
The liquid product selectivities of 4-vinylyridine were 87.8, 89.1, 97.0, and 68.7%
at 63.3, 64.4, 77.6, and 76.6% conversion of 4-picoline over lwt% K-ZSM-5
(SiO2/Al2O3= 30), 2wt%K-ZSM-5 (30), 3wt%K-ZSM-5 (30) and 4wt%K-ZSM-5 (30)
catalysts respectively. The experimental conditions were as given in Example-15.
Similarly the weight percent of cesium (Cs) was varied and conversion and selectivities
were studied (determined). The activity for Cs-ZSM-5 was lower than that for K-ZSM-5
catalysts.
EXAMPLE 23:
The liquid product selectivities of 4-vinylpyridine were 73.4, 63.9, 96.8, 59.9, and
51.6% at 28.8, 57.4, 49.3, 66.2, and 65.3% conversion of 4-picoline at 200, 250, 300, 350
and 400°C reaction temperature over 3wt% Cs-ZSM-5 (SiO2/Al2O3= 30) respectively.
The other experimental conditions were as given in Example-15.
EXAMPLE 24:
The liquid product selectivities of 4-vinylpyridine were 79.8, 96.8, 89.9, and
66.3% at 53.5, 49.3, 52.3, and 54.9% conversions of 4-picoline with 1:1, 1:2, 1:3, and 1:4
molar ratio of 4-picoline/formaldehyde respectively. The catalyst was 3wt% Cs-ZSM-5
(Si(VAl2O3= 30). The other experimental conditions were as given in Example-15.
EXAMPLE 25:
The liquid product selectivities of 4-vinylpyridine were 80.3, 96.8, 96.2, and
93.5% at 66.4, 49.3, 39.2, and 37.1% conversion of 4-picoline at 0.25, 0.5, 0.75 and 1.0 h"
1 weight hourly space velocities respectively. The catalyst was 3wt% Cs-ZSM-5
(Si02/Al2O3= 30) and formaldehyde/4picoline = 2 molar. The reaction temperature was
300°C. The other experimental conditions were as given in Example-15.
EXAMPLE 26:
With the experimental details as given in Example-15, the time on stream was
studied and steady state activity and yields were obtained for 8 hours on stream.
16






We Claim:
1. An improved process for the preparation of vinyl pyridine from corresponding picoline
over modified zeolite catalyst in vapour phase which comprises; reacting picoline with
formaldehyde with a molar ratio of formaldehyde to picoline in the range of 1:1 to 4:1, at
a temperature ranging between 200 to 450°C, at a weight hourly space velocity in the
range of 0.25 hr-1 - 1.00 hr-1 characterized in that over a modified commercial zeolite
catalyst, the said catalyst is selected from the group consisting of ZSM-5, X, Y,
mordenite and MCM-41 and modified with one or two element(s) from alkali and
alkaline earth metal ions to obtain the desired product
2. An improved process as claimed in claim 1, wherein the vinylpyridine obtained is
selected from 2-vinylpyridine and 4-vinylpyridine.
3. An improved process as claimed in claims 1&2, wherein Picoline used is selected from 2-
picoline and 4-picoline.
4. An improved process as claimed in claims 1-3, wherein the modification of the catalyst,
preferably ZSM-5 is carried out by alkali or alkaline earth metal ion selected from the
group consisting of Li+, Na+, K+, Rb+, Cs+, Mg+2, Ca+2, Sr+2, Ba+2 or two cation modified
ZSM-5 like Cs-K-ZSM-5.
5. An improved process as claimed in claims 1-4, wherein the weight percent of the alkali or
alkaline earth metal cation in ZSM-5 catalyst used is in the range of 1 to 4 wt%.
6. An improved process for the preparation of vinyl pyridine from corresponding picoline
over modified zeolite catalyst in vapour phase , substantially as herein described with
reference to the examples accompanying this specification.

Documents:

1092-DEL-2002-Abstract-(14-10-2008).pdf

1092-del-2002-abstract.pdf

1092-DEL-2002-Claims-(07-01-2010).pdf

1092-DEL-2002-Claims-(14-10-2008).pdf

1092-del-2002-claims.pdf

1092-DEL-2002-Correspondence-Others-(07-01-2010).pdf

1092-DEL-2002-Correspondence-Others-(14-10-2008).pdf

1092-del-2002-correspondence-others.pdf

1092-del-2002-correspondence-po.pdf

1092-DEL-2002-Description (Complete)-(07-01-2010).pdf

1092-DEL-2002-Description (Complete)-(14-10-2008).pdf

1092-del-2002-description (complete).pdf

1092-del-2002-form-1.pdf

1092-del-2002-form-18.pdf

1092-DEL-2002-Form-2-(14-10-2008).pdf

1092-del-2002-form-2.pdf

1092-DEL-2002-Form-3-(14-10-2008).pdf

1092-del-2002-form-3.pdf

1092-DEL-2002-Petition-137-(14-10-2008).pdf


Patent Number 248052
Indian Patent Application Number 1092/DEL/2002
PG Journal Number 24/2011
Publication Date 17-Jun-2011
Grant Date 13-Jun-2011
Date of Filing 30-Oct-2002
Name of Patentee COUNCIL OF SCIENTIFIC AND INDUSTRIAL RESEARCH
Applicant Address RAFI MARG, NEW DELHI-110001, INDIA
Inventors:
# Inventor's Name Inventor's Address
1 SHIVANAND JANARDAN KULKARNI INSTITUTE OF CHEMICAL TECHNOLOGY,HYDERABAD, 500 007, A.P.,INDIAN
2 GANGAPURAM MADHAVI INSTITUTE OF CHEMICAL TECHNOLOGY,HYDERABAD, 500 007, A.P.,INDIAN
3 VENKATARAMAN VISWANATHAN INSTITUTE OF CHEMICAL TECHNOLOGY,HYDERABAD, 500 007, A.P.,INDIAN
4 KONDAPURAM VIJAYA RAGHAVAN INSTITUTE OF CHEMICAL TECHNOLOGY,HYDERABAD, 500 007, A.P.,INDIAN
PCT International Classification Number C07D 213/38
PCT International Application Number N/A
PCT International Filing date
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 NA