Title of Invention

LAYERED AMALGAM AND ITS PRODUCTION

Abstract The invention relates to a method for production of a layer composite, comprising a metal support substrate and a silicate layer with the following method steps: a) production of the metal support substrate, b) production of silicate crystals and/or silicate particles by means of solvothermal synthesis, said solvothermal synthesis being carried out in at least one ionic liquid and c) coating of at least one surface of the metal support substrate with the silicate crystals and/or silicate particles produced in b).
Full Text Layered Amalgam and Its Production
The present invention relates to a metliod for producing a layered amalgam comprising a metallic
carrier layer and a silicate layer, and the usage of such layered amalgams in heat
pump technology.
Silicates are salt forms of the orthosilicic acids Si(0H)4 and their condensation products. They
are not only the most diverse class of minerals; they are also of major technical importance.
Glass, porcelain, enamel, earthenware, concrete and soluble glass are technically important
products that are made of silicates.
Silicates can be divided into the following groups according to their structure: a) silicates with
discrete anions like nesosilicates (inselsilicates, orthosilicates with anion [Si04]'*'), sorosilicates
(group-silicates, all [Si04]-tetrahedrons being combined in one finite group), cyclosilicates (ring
silicates, where [Si04]-tetrahedrons form rings), b) inosilicates (chain and band silicates, where
[Si04]-tetrahedrons form chains, i.e. one-dimensional unlimited shapes that can be seen as
polymers of the anion [SiOa] "), c) phyllosilicates (sheet and compound silicates, where the
[Si04]-tetrahedrons form a chain on one level, they form compound grids and can be seen as
polymers of the anion [Si40io]'^') and d) tectosilicates (frame silicates, where the
[Si04]-tetrahedrons form three-dimensional networks). Zeolites and feldspars are technically the
most important mineral silicates.
Zeolites are mineral silicates and especially aluminusilicates with a chemically complex structure
which is characterized through the formation of porous tetrahedron networks. According to the
general definition by IZA (International Zeolite Association) zeolites are minerals that form
tetrahedron networks with a network density of more than 19 tetrahedron atoms per 1000 A'.
Zeolites have a structure with inner hollow spaces that will reach the size of a molecule.
Therefore zeolites can incorporate foreign atoms or foreign molecules into their microporous
structure, e.g. zeolites can save huge amounts of water and release it when they are heated up.
Zeolite materials in contact with a heat exchanger can therefore be easily used to create a latent
heat store. According to the prior art, fills of zeolite or materials containing zeolites that are
WO 2007/017015 A2 Page 1

poured into open-pored solids like metal sponges that are in thermal contact with a heat
exchanger are used for this process. Please see DE 101 59 652 C2, for example, for this process.
Fills of zeolite are not suitable for applications that require heat addition to zeolites or heat
removal from zeolite materials because the thermal contact to the neighbouring heat exchanging
structures is insufficient. Furthermore, especially for latent heat stores, the working medium
customarily referred to as sorptive must be added as sorb material to the zeolite in an effective
manner. This requires macroscopic channel structures in the sorb material. For this reason the
pulverised synthesized zeolite will be pressed into bigger units in the shape of pellets with the
help of a binder for such purposes. Unfortunately most binders influence and change the relevant
properties of zeolites in a negative way. In addition, the usage of pellets does not guarantee
enough thermal contact to neighbouring heat exchangers. For this reason the usage of systems of
heat exchangers to which a zeolite coating is applied is recommended. Typically, in known
processes for coating substrates with zeolites there is first a synthesis interval where the zeolite
material is created. This zeolite material can be treated mechanically afterward, e.g. it can be
ground or reduced in size, so that a powdered zeolite is created. Afterward the pre-synthesised
zeolite material will be mixed with a binder and coated onto the carrier substrate.
However, it is very difficult to coat the whole surface of the heat exchanger with a zeolite
coating of uniform thickness, especially on complex three-dimensional heat exchange structures.
Furthermore, such a post synthesis coating process consists of many production steps. In
addition, most binders change the properties of zeolites because the molecules that are to be
bound do not have free access to the inner microporous structure of the zeolite particles.
A number of suggestions have been made with regard to the synthesis of silicates in the
literature. The most interesting ones are the sol-gel synthesis procedure and hydrothermal
synthesis. Hydrothermal synthesis is generally the synthesis of minerals and chemical
compounds through crystallization of highly-heated aqueous solutions, i.e. hydrothermal
solutions with a temperature of more than 100 °C and a pressure of more than 1 bar. In most
cases hydrothermal synthesis is carried out in pressure containers because the temperatures used
to carry out the process are far higher than the boiling point of water, most even above its critical
WO 2007/017015 A2 Page 2

temperature of TK "- 374 °C. In its supercritical state water dissolves some water-insoluble
materials. The increased ability to dissolve is most likely derived from compression because the
smaller physical distance increases the interaction with the dissolved material. Therefore there is
a possibility for producing mesoscopic inorganic colloids, crystals or powders in aqueous
systems during hydrothermal synthesis. This synthesis generally produces particles having a
diameter of only a few |Jm.
Apart from these procedures that have been known for some time, a new process for producing
silicate coatings through a spin coating procedure has recently emerged. The production of
porous coatings, porous coatings themselves and the use of these coatings in microelectronics are
described in WO 02/ 032 589 Al. The coatings can consist of periodically porous particles of
one zeolite where the particles have a diameter of only a few nanometers and the coatings have a
thickness of 30 to 1000 nm. The described coatings are applied to a silicon surface.
A major problem in the hydrothermal synthesis of silicates is nucleation, which determines the
morphology and the particle size distribution of the formed particles. In thermodynamic terms
the formation of seed crystals and generally all crystals or particles represents a phase formation
and is therefore subject to its own specific laws. Due to entropy decrease it is highly unlikely that
a spontaneous formation of particles will occur because particles consist of a number of particles.
Therefore a precipitation or a formation of particles, powders or crystals always requires an
induction phase in which the primary seed crystals are formed. A broad particle size distribution
and an energetically minimized particle surface are the result if the formation of seed crystals
during the induction phase is slow. If the formation of seed crystals is fast, growth will be
homogeneous, particle size will be small, and size distribution will be narrow.
The processes of nucleation in solution and/or on the substrate, transportation of seed crystals
onto the surface and their most homogeneous, lateral growth on the substrate surface are
necessary requirements for the precipitation of dense silicate coatings on a metallic substrate
during hydrothermal synthesis.
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Therefore one object of the present invention is to offer a process that can produce an even and
homogeneous coating of a metaUic carrier with silicates within a short coating time. A further
object of the invention is to offer a process for creating a silicate coating that consists of
individual particles with a very narrow particle size distribution. Moreover, a lateral
homogeneous precipitation of thick silicate coatings on a metallic substrate that can be achieved
directly shall be offered. Another object of the invention is to offer a layered amalgam that can
be produced using a cost-effective method.
These objects are attained with a process for the production of a layered amalgam made up of a
metallic carrier substrate and a silicate coating, comprising the following process steps:
a) preparation of the metallic carrier substrate, b) production of silicate crystals and/or silicate
particles through solvo-thermal synthesis in at least one ionic liquid and c) coating of at least one
surface of the metallic carrier substrate with the silicate crystals and/or silicate particles produced
inb).
Here and in what follows, a solvo-thermal synthesis is a hydrothermal analogue synthesis in a
solvent other than water, where the temperature and pressures are regulated according to the
various solvents. In this context a coating is a continuous substance layer that covers a whole
area with only very few surface defects. Further, an ionic liquid is a salt which is liquid at room
temperature and is made up of a complex inorganic cation or an organic cation containing
niti^ogen, oxygen, sulphur, phosphorous or other homologs as the heteroatom, and inorganic or
organic anions. Cation and anion can be formed through derivatization in such a way that they
require a lot of room and extend the area of existence of the solution. These ionic liquids have
very low melting points because they are sahs. In addition, ionic liquids have broad thermal fluid
area and good thermal stability and are hydrolysis-resistant. Because of their physicochemical
properties as melted salts, i.e. because cations and anions without solvate shells are freely
movable, ionic liquids generally have no intrinsic vapour pressure in thermal stabihty. It is as yet
unclear whether in isolated cases pairs of ions or even single ions can be vaporized from the
solution into the gas phase through thermal excitation. An overview of the types and properties
of ionic fluids can be found in P. Wasserscheid, T. Welton "Ionic Tiquids in Synthesis" Wiley
VCH2003.
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Surprisingly it has been discovered that nucleation is achieved 1000 times faster if at least one
ionic liquid is used as solvent in the solvothermal synthesis of silicates, in comparison with the
known hydrothermal synthesis. Therefore, if an ionic liquid and not water is used as the solvent
in the synthesis of silicate crystals and/or silicate particles, significantly shorter synthesis times
are possible, corresponding to about half the synthesis time in water. In addition, if at least one
ionic liquid is used as the solvent, the equipment that is more involved in terms of security
technology as compared with the known hydrothermal synthesis is not necessary. Because of
lower pressures in general the security equipment necessary for high pressures is not needed. It
was also surprising to see that the synthesis of undesired species that can be found in an aqueous
environment or when water is used as the solvent can be suppressed to a large extent. Another
advantage of the use of ionic liquids as the solvent in the solvothermal synthesis of silicates is
that the choice of anions and cations of ionic liquids adds properties to the solution that can be
achieved in hydrothermal synthesis only through the combination of water as solvent and
dissolved neutral molecules or electrolytes.
According to a second preferred process, the synthesis of silicate crystals and/or silicate particles
is carried out in a mixture of at least two different ionic liquids.
The ionic liquid or the mixture of at least two different ionic liquids used according to the
invention will preferably contain at least one salt made up of a hydrophilic or hydrophobic anion
X, particularly a hydrophilic or hydrophobic univalent, divalent or trivalent anion X"^" with m
1, 2 or 3 and a five- or six-sided, aromatic, partially saturated or unsaturated, nitrogen-containing
heterocyclene-cation, an ammonium cation or a guanidinium cation. Especially, the salt can be a
pyrrolium salt [Formula (I)], imidazolium salt [Formula (II)], imidazolidinium salt [Formula
(III), pyridinium salt [Formula (IV)], ammonium salt [Formula (V)] or a guanidinium salt
[Formula (VI)] with the following structures:
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wherein X'"" is a mono-, di- or trivalent anion with m = 1,2 or 3, wherein n is the number of
monovalent cations in the salt and has the value n = 1, 2 or 3, and n represents the valence of the
anion, wherein Rl can be an alkyl, alkene or aryl group, wherein R2 and R3 can be equal to or
different from hydrogen, an alkyl, alkene or aryl group, with the measure that R2 and R3 have
the same or different meanings, and at least one group of R2 or R3 is an alkyl, alkene or
aryl group,
wherein R4, R5, R6, R7 and R8- can be equal to or different from hydrogen, an alkyl, alkene or
aryl group with the measure that at least one group R4, R5, R6, R7 or R8 is an alkyl, alkene or
aryl group, and that R4, R5, R6, R7 and R8 can have the same or different meanings.
In particular, the ionic liquid or the mixture of at least two ionic liquids can thereby comprise at
least one salt, having a hydrophilic or hydrophobic anion X, especially a mono-, di- or trivalent
X*"" anion with m = 1, 2 or 3 and as a cation a five or six-sided, aromatic, partially saturated or
WO 2007/017015 A2 Page 6

unsaturated, nitrogen-containing heterocyclene cation, an ammonium cation or a guanidinium
cation according to one of the formulas I to VI.
wherein n is the number of monovalent cations in the salt and has the value n 1, 2 or 3, and n
corresponds to the valence of the anion, wherein Rl can be an alkyl, alkene or aryl group,
wherein R2 and R3 are equal to or different from hydrogen, an alkyl, alkene or aryl group, with
the measure that R2 and R3 can have the same or different meanings, and at least one group R2
or R3 is an alkyl, alkene or aryl group, wherein R4, R5, R6, R7 and R8 are equal to or different
from hydrogen, an alkyl, alkene or aryl group with the measure that at least one group R4, R5,
R6, R7 or R8 is an alkyl, alkene or aryl group and that R4, R5, R6, R7 and R8 can have the same
or different meanings, and wherein the alkyl group or alkene group is a linear, branched,
saturated and/or unsaturated alkyl group with a carbon chain length of C-1 to C-30 and
especially preferably is a methyl-, ethyl-, n-propyl-, 1-methylethyl-, n-butyl-, 1-methylpropyl-,
2-methylpropyl-, 1,1-dimethylethyl-, n-pentyl-, 1-methylbutyl-, 2-methylbutyl-, 3-methylbutyl-,
1-ethylpropyl-, 2-ethylpropyl-, 1,1-dimethylpropyl-, 1,2-dimethylpropyl-, 2,2-dimethylpropyl-,
n-hexyl-, 2-ethylhexyl-, n-heptyl-, n-octyl-, n-nonyl-, n-decyl-, n-undecyl- or n-dodecyl group.
In the invented process the preferred implementation of ionic liquid or the mix of at least
two ionic liquids includes at least one salt, comprising a mono- di- or trivalent X"^" anion with
m = 1, 2 or 3, and as a cation a five- or six-sided, aromatic, partially saturated or unsaturated,
nitrogen-containing heterocyclene cation, an ammonium cation or a guanidinium cation, as
shown in one of the formulas I to VI,
wherein n is the number of monovalent cations in the salt and has the value n ^-- 1, 2 or 3, and
n corresponds to the valence of the anion, wherein Rl can be an alkyl, alkene or aryl group,
wherein R2 and R3 can be equal to or different from hydrogen, an alkyl, alkene or aryl group,
with the measure that R2 and R3 can have the same or different meanings, and at least one group
R2 or R3 is an alkyl, alkene or aryl group,
wherein R4, R5, R6 , R7 and R8 can be equal to or different from hydrogen, an alkyl, alkene or
aryl group, with the measure that at least one group R4, R5, R6, R7 or R8 is an alkyl, alkene or
aryl group, and that R4, R5, R6, R7 and R8 can have the same or different meanings, and
wherein X'^" is an anion from the group tetrafluoro borate (BF4"), alkyl borate, especially
tetraalkyl borate (B(0R)4" with R=alkyl), especially triethylhexyl borate (C2H60)3(C6Hi20)B"),
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phosphate (P04^"), halogeno phosphate especially hexafluoro phosphate (PFe'), organic
phosphates especially alkyl phosphates or aryl phosphates (RO-PO3" with R - alkyl or aryl),
nitrate (NO3"), sulphate (S04^'), organic sulphates, especially alkyl sulphates or aryl sulphates
(ROSO3" with R = Alkyl or Aryl), organic sulfonates especially alkyl sulfonates or aryl
sulfonates (R-SO3" with R = Alkyl or aryl), especially toluol sulfonyl (p-CH3(C6H4)-S03").
carboxylate (R-COO" with R - alkyl), methanide ([HCR^R^] and [CR'^R'^R'"] with R^ R^ R'" -
CN, NO or NO2, wherein R^ R', R'" can be the same or different), halogen, especially fluoride
(F'j, chloride (Cf) or bromide (Br") or pseudohalogenide especially azide (N3"), cyanide (CN),
cyanate (OCN"), fulminate (R2CNO') with R = Alkyl or Aryl) or thiocyanate (SCN") and wherein
especially each alkyl group R of the X""' anions or, if two alkyl groups R are provided, each alkyl
group R of the X"^' anions is the same or different linear, branched, saturated and/or unsaturated
alkyl group with a carbon chain length of C-1 to C-30, and especially preferably a methyl-,
eth'yl-n-propyl-, 1-methylethyl-, n-butyl-, 1-methylpropyl-, 2-methylpropyl-, 1,1-dimethylethyl-,
n-pentyl-, 1-methylbutyl-, 2-methylbutyl-, 3-methylbutyl-, 1-ethylpropyl-, 2-ethylpropyl-,
1,1-dimethylpropyl-, 1,2-dimethylpropyl-, 2,2-dimethylpropyl-, n-hexyl-, 2-ethylhexyl-,
n-heptyl-, n-octyl-, n-nonyl-, n-decyl-, n-undecyl- or n-dodecyl group.
It is further preferred that the ionic liquid is comprised of 1,3-dialkylimidazolium cations and a
hydrophilic or hydrophobic anion X, especially a mono-, di- or trivalent X"' anion with m = 1, 2
or 3 according to Formula II,

wherein n is the number of monovalent cations in the sah and has the value n ^ 1, 2 or 3, and n
corresponds to the valence of the anions, wherein R2 and R3, independently of one another, can
be a linear, branched, saturated and/or unsaturated alkyl group with a carbon chain length from
C-1 to C-30, and wherein X"^" is an anion from the group tetrafluoro borate (BF4"), alkyl borate
(B(0R)4" with R = alkyl), phosphate (P04^"), halo geno phosphate (PY6" with Y = halogen), alkyl
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or aryl phosphate (RO-PO3" with R = alkyl or aryl), nitrate (NO3"), sulphate (S04^"), alkyl or aryl
sulphates (RO-SO3" with R - alkyl or aryl), alkyl or aryl sulfonates (R-SO3" with R - alkyl or
aryl), carboxylate (R-COO" with R = alkyl), niethanide ([HCR**R']" and [CR*^RV°]" with R^ R^
R'*^ = CN, NO or NO2, wherein R^ R', R'° can be the same or different), fluoride (F"), chloride
(CI"), bromide (Br'), azide (N3") cyanide (CN"), cyanate (OCN"), fulminate (R2CNO" with R =
alkyl or aryl) or thiocyanate (SCN'), and wherein each alkyl group R of the X"^' anions or, if two
alkyl groups R are provided, each alkyl group R of the X""" anions is the same or different linear,
branched, saturated and/or unsaturated alkyl group with a carbon chain length of C-1 to C-30.
It can especially also be preferred that the ionic liquid or the mixture of at least two ionic liquids
is comprised of 1,3-dialkyl imidazolium cations (Formula II, wherein R2, R3, independently of
one another, are alkyls) and a hydrophilic or hydrophobic X anion, especially mono-, di- or
trivalent anions X'"' with m - 1, 2 or 3,
wherein alkyl means, independently of one another, a linear, branched, saturated and/or
unsaturated alkyl group with a carbon chain length from C-1 to C-30, and especially means
methyl-, ethyl- n-propyl-, 1-methylethyl-, n-butyl-, 1-methylpropyl-, 2-methylpropyl-,
1,1-dimethylethyl-, n-pentyl-, 1-methylbutyl-, 2-methylbutyl-, 3-methylbutyl-, 1-ethylpropyl-,
2-ethylpropyl-, 1,1-dimethylpropyl-, 1,2-dimethylpropyl-, 2,2-dimethylpropyl-, n-hexyl-,
2-ethylhexyl-, n-heptyl-, n-octyl-, n-nonyl-, n-decyl-, n-undecyl- or n-dodecyl, and
wherein X""' is especially an anion from the group tetrafluoro borate (BF4'), alkyl borate,
especially tetraalkyl borate (B(0R)4" with R = alkyl), especially triethylhexyl borate
(C2H60)3(C6Hi2)B"), phosphate (P04^"), halo geno phosphate especially hexafluoro phosphate
(PFg"), organic phosphates especially alkyl phosphates or aryl phosphates (RO-PO3" with R ^
alkyl or aryl), nitrate (NO3"), sulphate (S04^"), organic sulphates, especially alkyl sulphate or aryl
sulphate (ROSO3" with R = alkyl or aryl), organic sulfonates, especially alkyl sulfonates or aryl
sulfonates (R-SO3" with R ^ alkyl or aryl), most especially toluol sulfonyl (p-CH3(C6H4)-S03"),
carboxylate (RCOO" with R = alkyl), methanide ([HCR^R*^]" and [CR^R'^R"']" with R^ R^ R'° -
CN, NO or NO2, wherein R^ R', R"^ can be the same or different), halogen, especially fluoride
(F"), chloride (CI") or bromide (Br") or pseudohalogenide especially azide (N3") cyanide (CN),
cyanate (OCN"), fulminate (R2CNO" with R = alkyl or aryl) or thiocyanate (SCN'), and wherein
especially each alkyl group R of the anions X"^' or, if two alkyl groups R are provided, each alkyl
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group R of the anions X""" is the same or a different linear, branched, saturated and/or
unsaturated alkyl group with a carbon chain length of C-1 to C-30 and further is especially
preferably a methyl-, ethyl- n-propyl-, 1-methylethyl-, n-butyl-, 1-methylpropyl-,
2-methylpropyl-, 1,1-dimethylethyl-, n-pentyl-, 1-methylbutyl-, 2-methylbutyl-, 3-methylbutyl-,
1-ethylpropyl-, 2-ethylpropyl-, 1,1-dimethylpropyl-, 1,2-dimethylpropyl-, 2,2-dimethylpropyl-.
n-hexyl-, 2-ethylhexyl-, n-heptyl-, n-octyl-, n-nonyl-, n-decyl-, n-undecyl- or n-dodecyl group.
According to an especially preferred process, the ionic liquid or the mixture of at least two ionic
liquids is comprised of a minimum of one l-alkyl-3-methylimidazolium halogenide [Formula
(II) wherein R3 = methyl and R2 ^ alkyl], wherein alkyl means a linear or branched, saturated
carbon with a carbon chain length from C-1 to C-30, and especially is a methyl-, ethyl- n-propyl-
, 1-methylethyl-, n-butyl-, 1-methylpropyl-, 2-methylpropyl-, 1,1-dimethylethyl-, n-pentyl-,
1-methylbutyl-, 2-methylbutyl-, 3-methylbutyl-, 1-ethylpropyl-, 2-ethylpropyl-,
1,1-dimethylpropyl-, 1,2-dimethylpropyl-, 2,2-dimethylpropyl-, n-hexyl-, 2-ethylhexyl-,
n-heptyl-, n-octyl-, n-nonyl-, n-decyl-, n-undecyl- or n-dodecyl group, and wherein halogenide is
chloride or bromide.
There are further possibilities for anion-cation combinations which can be suitable for ionic
liquid. In particular, through the systematic combination of anion and cation salts, ionic liquids
as solvothermal solvent phases can be produced with specific properties, such as, for example, a
melting point and thermal stability. In a preferred variant of the invention the ionic liquid
represents a Bronsted acid and/or its salt, and serves thereby as a proton/cation source and/or
contains a Bronsted acid and/or its salts, which serve as a proton/cation source.
In addition, it can further be foreseen that the ionic liquid or the mixture of at least two ionic
liquids additionally comprises promoter ions, wherein these are selected from the group of
phosphate {P04^'), organic phosphates (RO-PO3'), nitrate (NO3"), sulphate (S04^"), organic
sulphates (RO-SO3"), carboxylate (R-COO"), methanide ([HCRV^]" or [CR^R'^R'"]' with R^ R^
R'" = CN, NO or NO2, wherein R^ R^ R'^ can be the same or different), fluoride (F"), chloride
(Cr), bromide (Br"), azide (N3"), cyanide (CN"), cyanate (OCN), fulminate (R2CNO") or
thiocyanate (SCN"). In particular, the organic groups R can be an alkyl residue. These promoter
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ions can be added as an additive to an ionic liquid in any form, i.e. independent of an
attached counterion.
In ionic liquids, inorganic syntheses and especially silicate syntheses can be conducted under
relatively mild conditions, which lead to a targeted synthesis of silicates with defined structural
components. On one hand, synthesis can be carried out under temperatures that are below a
specific level; the synthesis can especially be conducted at a temperature under 250 °C,
especially under 200 °C and especially preferably between 50 °C and 150 °C. On the other hand,
the synthesis can be carried out in a water-free or controlled water-containing environment. In
an especially preferred process, synthesis is carried out in a controlled water-containing
environment, wherein the amount of water is at most double the amount of the stoichiometric
parts of water based upon the quantity necessary for the synthesis of the respective silicates. In
such a reaction medium, secondary reactions, which take place in a hydrothermal synthesis based
upon system conditions, is almost completely suppressed, whereby a nearly optimal reaction
condition for targeted synthesis is made available. Afterwards, in a preferred method of the
invention, the synthesis of silicates is performed at the highest at 150 °C and especially 50 °C to
150 °C and especially in an autoclave at 50 °C to 150 °C. In particular the synthesis of silicates
is carried out in an autoclave at 50 °C to 150 °C and with a quantity of water that is at most
double the stoichiometric quantity in relation the silicate to be synthesized. The autoclave is a
closed vessel which remains closed during the entire reaction time, so that the total pressure
established with the dialled-in temperature is maintained. With this, the solvothermal conditions
are established in a very simple way. Through the use of ionic liquids as solvents and the
controlled amount of water, the high-pressure autoclaves that are necessary for hydrothermal
synthesis can be dispensed with.
In addition, it can be foreseen that the solvothermal synthesis can be carried out in an autoclave
system with convection. This convection establishes a laminar flow on the metallic carrier
substrate surface. Through this, the surface is supplied with an especially even concentration of
synthesized silicates, or with the even concentration of dissolved components established with
the laminar flow, a very uniform growth of silicates on the metal surface results. This represents
a significant difference from the classic hydrothermal synthesis, in which only a material
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transport through convection in a gravity field is ensured, which is supported by an internal
stirring process, which does not for its part lead to a laminar flow. In particular, this is a process
in which the process steps (b) and (c) can be carried out at the same time. In an especially
preferred process the synthesis of the silicates follows process step (b) and the coating follows
process step (c) in a muhi-chamber autoclave, so that the process steps (b) and (c) can be carried
out at the same time. A multi-chamber autoclave is understood to be a pressure vessel which has
at least two compartments, wherein each compartment is isothermically isolated from the
remaining compartments. In a first compartment, the metal carrier substrate is brought in,
whereas in the at least second compartment a convection current is present, through which a
laminar current is generated on the surface of the metal carrier substrate. With this, there can be
a fast nuclear build-up at each point in the ionic liquid caused by the ionic liquid, and these
nuclei can be placed in a very uniform concentration on the metallic surface, and/or a very
homogenous nuclear formation can take place on the metallic surface. This homogeneous
nuclear formation in the ionic liquid and/or on the metallic surface of the carrier substrate causes
a growth of homogenous silicate layers on the metal surface.
In the manufacture of the particles, crystals or the resulting or in-situ constructed layers, the ionic
liquids can further be used as stabilizing agents on the surface of the growing particles. Anionic
or cationic constructed parts can thereby take over the role as stabilisers, which in the classic
systems are added as molecular additives. In this way, solvothermal systems can be built, which
significantly extend the property and application spectrum of classic water-based systems.
With the method recommended here, a layered amalgam can be produced whose silicate layer is
very homogeneous with regard to its layer thickness at each part of the layered amalgam, and in
addition is very homogeneous with regard to the individual particles from which the silicate layer
is made. Through the faster nucleus build-up, as compared with classic hydrothermal synthesis,
the nucleus build-up is easier in comparison with particle or crystal growth. Therefore, particles
or crystals and layers result from the recommended process, which have a very narrow particle
size distribution. This narrow particle size distribution in turn guarantees a homogeneous silicate
layer on the metal carrier substrate. A cohesive silicate layer will therefore be attained by newly
formed nuclei growing on already established nuclei on the metal carrier substrate.
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Accordingly, in a preferred method an especially homogeneous silicate layer can have a layer
thickness of at least 10 microns, especially 10 microns and at the highest 200 microns, and most
especially at least 50 microns and at the highest 150 microns. In a further preferred method, the
silicate layer has particles or crystals that have a particle diameter of at most 200 nm, especially
10 to 150 nm.
In keeping with the classic synthesis method for silicates and especially for zeolites, the starting
materials necessary for the build-up of the silicate structure or the zeolite structure are placed in
an aqueous solution or suspension. Such an aqueous suspension comprises a first component,
which is a source for cations from the first or second main group of the Periodic Table, and
water. In addition, there is a second component, which is a source for at least a network building
eleinent from the third, fourth or fifth main group of the Periodic Table. The amount of water in
the solution or suspension is chosen such that at most a double stoichiometric quantity that
corresponds to the silicate to be synthesized is present.
In particular, with the above-mentioned new method, a synthesis of aluminium silicates and
especially of zeolites of the general formula (VII) can be carried out:
M2/zO • AI2O3-X Si02 ■ yUiO (VII)
wherein M: is one or more as a cation from the group of alkali or alkaline-earth elements,
hydrogen and/or ammonia,
Z: is the valence of the cation or the total of the valences of the cations,
X: is 1.8 to 12, and
Y: is 0 to 8.
The further synthesis conditions for the manufacture of durable silicate layers or zeolite layers on
the metal carrier substrate can be chosen within the framework of the expert measurement
according to the classic silicate synthesis. In this, as the metallic carrier substrates especially a
metallic substrate made of copper, aluminium, iron, alloys of these, or stainless steel should
be chosen.
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With the above-described invention, a layered amalgam is further produced via the
above-described process. This layered amalgam can especially be used in a heat exchanger.
Accordingly, with the present invention a heat exchanger is also recommended, which is
produced using the above-described process. These layered amalgams are especially
characterized by an effective energy transfer in a heat exchanger.
In particular, with the present invention a heat exchanger is also proposed, which has a metallic
carrier substrate and a silicate layer, which in turn contains silicate particles or silicate crystals,
which have a maximal particle size of 200 nm, especially maximally 150 nm and especially
preferably a particle size of 50 to 150 nm.
In what follows, the method will be detailed with reference to an exemplary embodiment.

WO 2007/017015 A2

Page 14

Claims
1. Method for the manufacture of a layered amalgam comprising a metallic carrier substrate
and a silicate layer with the method steps
a) prepare the a metallic substrate,
b) produce silicate crystals and/or silicate particles using solvothermal synthesis
c) coat at least one surface of the metallic carrier substrate with the silicate crystals
and/or silicate particles produced under (b), characterized in that the solvothermal synthesis is
carried out in at least one ionic liquid.

2. Method according to claim 1 characterized in that the synthesis is carried out in a mixture
of at least two different ionic liquids.
3. Method according to claim 1 or 2 characterized in that the ionic liquid comprises
1,3-dialkylimidazolium cations and hydrophilic or hydrophobic anions X, especially mono-,
di-or trivalent anions X"^" with m = 1, 2 or 3, wherein alkyl, independently of one another, refers
to a linear, branched, saturated and/or unsaturated alkyl group with a carbon chain length of C-1
to C-30.
4. Method according to at least one of the above-named claims through which it is
deihonstrated that the ionic liquid comprises at least a l-alkyl-3-methylimidazolium halogenide,
wherein alkyl refers to a linear or branched and/or saturated or unsaturated hydrocarbon with a
carbon chain length of C-1 to C-30, and wherein halogenide means chloride or bromide.
5. Method according to at least one of the above-named claims through which it is
demonstrated that the ionic liquid further comprises promoter ions, which are different from the
anions of the ionic liquids, and that these promoter ions are chosen from the group of phosphate
(P04^"), organic phosphates (RO-PO3"), nitrate (NO3"), sulphate (S04^"), organic sulphates
(RO-SOsO, carboxylate (R-COO"), methanide ([HCRV]" and [CRVR'*^]' with R\ R^ R'"
CN, NO or NO2, wherein R^ R'^, R'° can be the same or different), fluoride (F), chloride (Cf),
WO 2007/017015 A2 l^igiTs

bromide (Br-), azide (N3"), cyanide (CN), cyanate (OCN"), fulminate (R2CNO") or
thiocyanate (SCN').
6. Method according to claim 1 or 2 characterized in that the synthesis of silicate crystals
and/or silicate particles is conducted in an autoclave at a maximum of 150 °C, especially in the
form of a solvothermal synthesis in an autoclave with convection current.
7. Method according to at least one of the above-mentioned claims through which it is
demonstrated that the method step (b) produce the silicate crystals and/or silicate particles and
the method step (c) coat the carrier substance are performed at the same time.
8. Method according to at least one of the above-named claims through which it is
demonstrated that the metallic substrate is made of copper, aluminium, iron, alloys of these, or
stainless steel.
9. Method according to at least one of the above-named claims through which it is
demonstrated that the silicate layer consists of an aluminium silicate, preferably a zeolite of the
general formula
M2/zO • AI2O3 - xSi02 • yH20 (VII)
wherein M: is one or more a cation from the group of alkali or alkaline-earth elements,
hydrogen and/or ammonia,
Z: is the valence of the cation or the sum of the values of the cations,
X: is 1.8 to 12, and
Y: is 0 to 8
10. Method according to at least one of the above-named claims through which it is
demonstrated that the silicate layer comprises silicate crystals and/or silicate particles which have
a maximum particle diameter of 200 nm and especially 10 to 150 nm.
WO 2007/017015 A2 Page 16

11. Method according to at least one of the above-named claims through which it is
demonstrated that the silicate layer has a layer thickness of at least 10 microns, especially from at
least 10 microns to a maximum of 200 microns and especially preferably from at least
50 microns to a maximum of 150 microns.
12. Layered amalgam produced according to at least one of the above-named claims.
13.. Heat exchanger comprising a layered amalgam according to claim 12.
14. Use of a layered amalgam according to claim 12 for energy exchange in a
heat exchanger.




WO 2007/017015 A2

Page 17

The invention relates to a method for production of a layer composite, comprising a metal support and a silicate layer with the following method steps: a) production of the metal support substrate, b) production of silicate crystals and/or silicate particles by means of solvothermal synthesi, said solvothermal synthesis being carried out in at least one ionic liquid and c) coating of at least one surface of the metal support substrate with the silicate crystals and/or silicate particles
produced in b) .

Documents:

01029-kolnp-2008-abstract.pdf

01029-kolnp-2008-claims.pdf

01029-kolnp-2008-correspondence others.pdf

01029-kolnp-2008-description complete.pdf

01029-kolnp-2008-form 1.pdf

01029-kolnp-2008-form 2.pdf

01029-kolnp-2008-form 3.pdf

01029-kolnp-2008-form 5.pdf

01029-kolnp-2008-international publication.pdf

01029-kolnp-2008-pct request form.pdf

1029-KOLNP-2008-(16-05-2013)-CORRESPONDENCE.pdf

1029-KOLNP-2008-(16-05-2013)-DESCRIPTION (COMPLETE).pdf

1029-KOLNP-2008-(16-05-2013)-FORM-1.pdf

1029-KOLNP-2008-(16-05-2013)-FORM-2.pdf

1029-KOLNP-2008-(16-05-2013)-OTHERS.pdf

1029-KOLNP-2008-(19-07-2013)-CORRESPONDENCE.pdf

1029-KOLNP-2008-(19-07-2013)-OTHERS.pdf

1029-KOLNP-2008-(19-07-2013)-PETITION UNER SECTION 8(1).pdf

1029-kolnp-2008-CANCELLED PAGES.pdf

1029-KOLNP-2008-CORRESPONDENCE 1.1.pdf

1029-kolnp-2008-CORRESPONDENCE.pdf

1029-kolnp-2008-DECISION.pdf

1029-kolnp-2008-EXAMINATION REPORT.pdf

1029-kolnp-2008-FORM 18-1.1.pdf

1029-kolnp-2008-form 18.pdf

1029-kolnp-2008-FORM 26.pdf

1029-kolnp-2008-GRANTED-ABSTRACT.pdf

1029-kolnp-2008-GRANTED-CLAIMS.pdf

1029-kolnp-2008-GRANTED-DESCRIPTION (COMPLETE).pdf

1029-kolnp-2008-GRANTED-FORM 1.pdf

1029-kolnp-2008-GRANTED-FORM 2.pdf

1029-kolnp-2008-GRANTED-FORM 3.pdf

1029-kolnp-2008-GRANTED-FORM 5.pdf

1029-kolnp-2008-GRANTED-LETTER PATENT.pdf

1029-kolnp-2008-GRANTED-SPECIFICATION-COMPLETE.pdf

1029-kolnp-2008-INTERNATIONAL PUBLICATION.pdf

1029-kolnp-2008-INTERNATIONAL SEARCH REPORT & OTHERS.pdf

1029-kolnp-2008-OTHERS.pdf

1029-KOLNP-2008-PA.pdf

1029-kolnp-2008-PETITION UNDER RULE 137.pdf

1029-kolnp-2008-REPLY TO EXAMINATION REPORT.pdf


Patent Number 262761
Indian Patent Application Number 1029/KOLNP/2008
PG Journal Number 37/2014
Publication Date 12-Sep-2014
Grant Date 11-Sep-2014
Date of Filing 10-Mar-2008
Name of Patentee SORTECH AG
Applicant Address WEINBERGWEG 23, 06120 HALLE
Inventors:
# Inventor's Name Inventor's Address
1 WOLF, MARKUS AM DORFBACH 16A, 79111 FREIBURG
2 JASCHKE, STEFAN IM BESCH 4, FL-9494 SCHAAN
PCT International Classification Number B01J 20/18
PCT International Application Number PCT/EP2006/006417
PCT International Filing date 2006-07-01
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 10 2005 038 044.1 2005-08-10 Germany