TWI549910B - Method of preparing trialkoxysilane - Google Patents

Description

Method for preparing trialkoxysilane Field of invention

The present invention relates to a process for preparing a trialkoxysilane. More specifically, it relates to a process for preparing a trialkoxysilane represented by SiH(OR) ₃ wherein R is a C ₁ -C ₃ methyl, ethyl or propyl group.

Background of the invention

The number in brackets [ ] refers to the number of the document incorporated herein by reference.

Trialkyloxane has been widely used in various fields, for example, in the production of tannic acid oligomers of solar energy or semiconductors, the production of decane, hydrazine, and the like.

The method of synthesizing trialkoxydioxane is divided into two basic methods. A method of synthesis in a fixed bed or fluidized bed in a vapor-gas environment. The synthesis in a vapor-gas environment is carried out by passing the vaporized alcohol through a crucible comprising a catalyst in a fixed bed or a fluidized bed. However, fixed bed reactors are not widely used because it is difficult to maintain the entire reactor at a uniform and constant temperature. If the synthesis is carried out directly on a fluidized bed, the above disadvantages can be eliminated.

According to reference [1], diluting the vaporized alcohol with a gas suppresses or minimizes the temperature increase of the fluidized bed. The diluent gas may be argon, nitrogen, helium, neon, hydrogen, and other gases. However, if supplemental materials are applied, the manufacturing cost will increase, and the addition of the inert gas will increase the trialkoxide. With the loss of alcohol. The synthesis under reduced pressure can improve the yield of the target material trimethoxy decane. At this point, under normal pressure, the enthalpy conversion rate is 90%, and the selectivity is 84.2% and 65% and 48.8%, respectively. However, when the pressure is lowered, the reaction rate is lowered, thereby lowering the yield.

Reference [2] suggests a technique for passing hydrogen and vaporized alcohol through a contact substance. If hydrogen is applied in the manufacture of a trialkoxide, equipment for preparing and purifying hydrogen is required, thus increasing the manufacturing cost. When the contact substance is activated by nitrogen and zinc is added as an accelerator at a reaction temperature of 280 ° C or lower, the content of triethoxy decane contained in the reaction mixture is 87%, and has a very low enthalpy conversion rate of 23 %.

The activation of the contact species including ruthenium and the catalyst is carried out stepwise at 450 ° C or lower in [1] and in the range of 300 to 350 ° C in references [2] and [5]. Under nitrogen, or other inert gas atmosphere.

References [6] to [9] disclose a method of applying hydrogen gas for activating ruthenium and a catalyst. The hydrogen activation system is carried out in a fixed bed or a fluidized bed at about 400 °C. The mixture of rhodium and catalyst comprises 1.5% or more copper. However, its selectivity, reactivity, and reaction stability were not provided.

Referring to references [1] to [9], the synthesis reaction in a fluidized bed to obtain triethoxyoxane results in the yield of triethoxyoxane and the conversion of ruthenium if the reaction is carried out under atmospheric pressure. The rate is not high. If the reaction is carried out under reduced pressure, the main synthetic index increases, but the advantages are offset by the technical characteristics. In addition, if the liquefied material is further injected together with the alcohol, it is synthesized in the fluidized bed, although some are combined. The index has increased, but it will cause problems. Because of the cockroaches and catalysts, a filtration process is needed.

Another synthesis method is a direct reaction with an alcohol in a liquid solvent in a reactor equipped with a stirring apparatus in the form of a suspension. Recently, this method has been widely used because by using a solvent, the temperature is maintained uniform in the reaction mixture, the overheating reaction environment is greatly reduced, and the side reaction is suppressed, and the selectivity of the trialkoxide and the ruthenium The conversion rate has increased.

Since the synthesis reaction of the trialkoxysilane is carried out at a high temperature of about 300 ° C, the solvent used in the synthesis reaction cannot be decomposed at this high temperature. The solvent should be capable of maintaining a uniform temperature in the reaction system. Further, the niobium powder needs to be uniformly dispersed in the solvent, and the solvent does not cause oxidation in a reaction temperature range from 100 to 300 °C.

References [10] and [11] suggest alkylating benzene, while reference [12] suggests alkylating naphthalene - "THERMINOL" oil. THERMINOL ^® 59, 60, 66; DOWTHERM ^® HT, MARLOTHERM ^® S, MARLOTHERM ^® and others are disclosed in detail in references 13 and 25.

In references [13], [14] and [15], the amount of solvent used in the synthesis reaction is determined such that the ratio of solvent: hydrazine can be from 1:2 to 4:1, preferably from 1:1 to The number of 2:1.

According to references [16] to [20], after the reaction material of hydrazine and alcohol is added, the activation of the reaction requires a long induction period, for example, 1 to 12 hours. It is known that this induction period is mainly required because an oxide film is formed on the surface of the crucible. In order to shorten the induction period, it is necessary to synthesize a trialkoxide. An activation step is added to the reaction.

A method of activation is described in detail in reference [13]. The activation process can be carried out in a reactor or in separate equipment. The hydrazine activated in a separate apparatus can be transferred to a reactor in a dry inert environment. The activation reaction is carried out at 20 to 400 ° C, preferably 150 to 300 ° C. Hydrogen and nitrogen are used as the activating gas, and methanol is used to activate the reaction between hydrazine and ethanol because methanol is more active than hydrazine or higher alcohol. For example, if 5% methanol is added to ethanol, the reaction rate is greatly increased. In this regard, the use of hydrogen and nitrogen at 150 to 250 deg.] C, 1kg of activating comprises silicon, copper hydroxide and 14.1g of 2.1kg as a reaction solvent MARLOTHERM ^® S of the suspension over a period of 65 minutes. Methanol was added at a rate of 4.3 g/min at 250 ° C for 5 hours. Thereafter, the temperature was lowered to 230 ° C, and then the supply of methanol was stopped, however, the supply of ethanol was maintained at a constant rate, in which the supply of hydrogen was stopped, while the supply of nitrogen was maintained. The total amount of active material is calculated stoichiometrically and adjusted to an amount sufficient to convert the divalent or monovalent copper catalyst to free copper. In fact, the activation process takes a long time, and it must be equal, because of the large surface of the bismuth-copper material, in which the diameter of the ruthenium particles is in the range of 50 to 300 μm. In the meantime, the particle size of the catalyst is limited. The size of the microparticles needs to be in the range of 1 to 100 μm, preferably 0.1 to 50 μm, more preferably 0.1 to 30 μm. Meanwhile, the specific surface area of the catalyst in the raw material may be in the range of 0.1 to 2 m ² /g, preferably 10 to 50 m ² /g. The direct synthesis using hydrazine can be carried out in both periodic mode as well as continuous mode. In terms of the periodic mode, although all of the hydrazine is added to the reaction at an early stage, the alcohol is continuously supplied until the reaction of hydrazine is terminated. Depending on the yield, a predetermined amount of hydrazine may be provided intermittently, however the alcohol system is continuously supplied. In the continuous mode, rhodium or a catalyst-containing rhodium can be added to the reactor after the start of the operation. In this regard, the amount of catalyst can be minimized or adjusted so as not to cause side reactions that decompose alcohol. The reaction temperature may be 150 ° C or higher, not exceeding the temperature at which the alcohol and the solvent are decomposed. The reaction can be operated in the range of 200 to 260 °C. The temperature suitable for the reaction of methanol may be 220 to 250 ° C, and the temperature suitable for the reaction of ethanol may be 200 to 240 ° C. The direct synthesis of the trialkoxysilane can be carried out regardless of the pressure, preferably at atmospheric pressure.

References [21] and [22] suggest treating ruthenium with hydrogen fluoride in order to reduce the induction period by removing the oxide film from the surface of the ruthenium before the start of the reaction.

References [10] and [22] suggest that the reaction mass is activated by maintaining a high temperature in a nitrogen, argon or any other inert gas atmosphere, while reference [23] suggests premixing in a grinder in an inert gas atmosphere.矽 with catalyst for 8 hours.

Reference [21] discloses an injection alkyl chloride, hydrogen chloride or ammonium chloride prior to the synthesis, the activated silicon is used, but Reference [24] discloses an injection such as NH ₄ HF ₂ of halide. However, if a halide, an alkyl halide, methanol or the like is added to the reactor prior to the synthesis reaction, a distillation step is additionally required to remove the impurities, thus complicating the manufacturing process of the trialkoxysilane.

Therefore, in the direct synthesis of trialkoxydecane, the induction period is not simply understood, and no effective method for reducing the induction period has been found. If additional reagents are added to the synthesis, the step of further removing the reagents is required, which complicates the manufacturing process of the trialkoxide. And increase manufacturing costs.

Referring to references [11], [13], [14], [17], and [21], the main synthesis reaction of trialkoxane produces oligoalkane, moisture, and other vices due to side reactions. The reaction product, and the accumulation of such side reaction products, reduces the reaction rate. Referring to the reference [14], since the metal contained in the catalyst is a foreign matter in the hydrazine synthesis reaction, metallic copper due to decomposition of the catalyst is accumulated in the solvent. The accumulation of residual ruthenium, impurity-containing ruthenium, and trialkoxide reduces the reaction rate. In this case, in order to reuse the solvent in the synthesis of the trialkoxide, the solvent should be reconstituted.

In order to improve the efficiency of the main synthesis index of the trialkoxysilane, aluminum (amount of 0.01 to 10%, preferably 0.1 to 2%, reference [16]), zinc (reference [2]), and phosphorus oxide are used. And single or multiple bonds of organic or non-organic compounds (Ref. [25]) as reaction accelerators for trialkoxides. However, no information about its effects has been revealed.

Reference [1] discloses a process for preparing a trialkoxysilane which comprises a pulverization step of ruthenium and reacting the pulverized ruthenium with an alcohol in the presence of a catalyst.

Industrial ruthenium pulverized into a particle size of 500 μm in air was used as a reactant. Ethanol and methanol are used as the alcohol reagent, and a copper-containing compound such as copper chloride (CuCl) is used as the catalyst. They are mixed with the pulverized ruthenium, and then the mixture is preheated at 300 ° C or lower for several hours to activate the catalyst, thereby activating the interaction between the alcohol and the hydrazine. This technique can also be applied to other methods similar to those of the reference [1]. In order to promote the interaction between the hydrazine and the alcohol, a halide is added to the additional catalyst, including a halogen element. Examples of organic and non-organic materials are chlorides, fluorides, methyl bromide, ethyl bromide, trichloroethylene, hydrogen fluoride (HF), hydrogen chloride (HCl), HBr, and HI. This method has various disadvantages despite its advantages. Among these disadvantages, preheating the catalyst at a temperature of 300 ° C or lower for a long period of time causes additional energy loss, whereby the total process time is increased and the energy consumption is increased. In addition, the application of gaseous halides to activate the process is not environmentally safe.

Reference [26] discloses a method comprising a pulverization step of ruthenium and an interactive reaction step of pulverizing ruthenium with an alcohol in a heated solvent environment (wherein the reagent has been activated). The pulverization of the crucible was pulverized in the air to a particle size of 500 μm using a ball mill. Ethyl alcohol and methanol are used as the alcohol reagent, and triethoxy decane or trimethoxy decane is obtained as the final product. A copper-containing compound such as copper chloride (CuCl) is used as a catalyst. The polyaromatic oil is used as a solvent, and the main technical process of the interaction between the pulverized hydrazine and the alcohol is carried out in a hot environment of 200 °C. Here, the application of the activating reagent technique is based on the following reasons. In the preparation of the trialkoxide, impurities contained in the raw material are accumulated in the reaction material, so that the reaction material cannot be uniformly consumed, and a part of the solvent is consumed together with the impurities in the side reaction, thus leaving no The reaction 矽. Therefore, the technique of activating the reagent is applied thereto. This technique involves withdrawing and precipitating a suspension of the reaction mixture comprising unreacted hydrazine, adding an appropriate amount of solvent, and recovering the concentrated suspension from the catalyst. This operation is carried out several times during the process when unreacted ruthenium accumulates in the reactor as a deposit. As with other similar methods, although the side reactions are reduced, the yield of the product is increased, the loss of raw materials is reduced, and the yield is increased, the process is very The complexity is because the unreacted helium is separated to replenish the lost solvent and catalyst, and the concentrated mixture of solvent and catalyst is periodically added to the reaction mass. In addition, since the reaction may be slowly slowed down when the reagent is added in a feed-in manner to supplement the consumption, it is not considered to exclude or reduce the induction period.

Quoted references patent

[1] US Patent No. 5,260,471: Process for producing trialkoxysilane / Yashinori Yamada 1993.

[2] US Patent No. 3,072,700: Process for producing silanes / Nicolas P.V. de wit 1963.

[3] Japanese Patent No. 06065258: Preparation of trialkoxysilanes / Harada, Masayoshi, Yamada, Yoshinori, 1994.

[4] GB Patent No. 2263113: Process for producing trialkoxysilanes / Yamada, Yoshinori, Harada, Katsuyoshi, 1993.

[5] Japanese Patent No. 05178864: Preparation of trialkoxysilanes / Yamada, Yoshinori, Harada, Masayoshi, 1993.

[6] US Patent No. 3,641,077: Method for preparing alkoxy derivatives of silicon germanium tin thallium and arsenic / Rochov E.G. 1972.

[7] US Patent No. 2,380,997: Contact masses / Patnode Winton, 1945.

[8] US Patent No. 2,473,260: Preparation of tetramethyl silicate / Rochov E.G. 1946.

[9] US Patent No. 4,314,908: Preparation of reaction mass for the production of methylchlorosilane / Downing James; Wells James, 1982.

[10] US Patent No. 4,727,173: Process for producing trialkoxysilanes / Mendicino F.D. 1988.

[11] US Patent No. 3,775,457: Method of manufacturing alkoxysilanes/ Hisashi Muraoka, Yokohama, Kanagawa-ken, 27.11.73.

[12] US Patent No. 762,939: Process for trialkoxysilane/tetraalkoxysilane mixtures from silicon metal and alcohol, 1988.

[13] US Patent No. 5,783,720: Surface-active advantages in the direct synthesis of trialkoxysilanes / Mendicino, Frank, Childress, 1998.

[14] US Patent No. 6,090,965: Removal of dissolvent silicates from alcohol-silicon direct synthesis solvents / K.M.Lewis, Hua Yu, 2000.

[15] US Patent No. 5,166,384: Method for the removal of siloxane dissolved in the solvent employed in the preparation of trimethoxysilane via methanol-silicon metal reaction / Donald L. Bailey, Thomas E. Childress, Newport, Both of Ohio, 1992.

[16] US Patent No. 5,362,897: Process for producing trialkoxysilane / Katsuyoshi Harada, Yashinori Yamada, 1994.

[17] US Patent No. 4,931, 578: Process for the preparation of alkoxysilane / Yoshiro Ohta, Kamiida-chou, Izumi-ku, 1990.

[18] Japanese Patent No. 06312994: Preparation of alkoxysilanes/ Harada, Masayoshi, Yamada, Yoshinori, 1994.

[19] Japanese Patent No. 06312992: Preparation of alkoxysilanes/ Harada, Masayoshi, Yamada Yoshinori, 1994.

[20] Japanese Patent Application Publication No. sho50-34540: Alkoxysilanes /Masafumi Asano, Kawasaki, Taizo Ohashi, 1984.

[21] Japanese Patent Application Publication No. sho51-1692: Process for producing trialkoxysilanes / Hisashi Muraoka, Yokohama, Masafumi Asano, 1976.

[22] US Patent No. 5,177,234: Preparation of alkoxysilanes by contacting a solution of hydrogen fluoride in an alcohol with silicon / Binh T. Nguyen, 1993.

[23] US Patent No. 4,487,949: Process for preparation of alkyl silicates/ Charles B. Mallon, Belle Mead, N.J., 1984.

[24] EP Patent No. 517398: Preparation of Alkoxysilanes using HF (salt), silicon, and alcohol/ Bank, Speier, John Leopold, 1992.

[25] WO 2007/032865: Process for the direct synthesis of trialkoxysilane.

[26] Russian Patent No. 2235726 C1: Method of preparation alkoxysilanes/ Gorshkov A.S., Markacheva A.A., Storozhenko P.A., 2003.

The above information is disclosed in this Background section only to enhance the understanding of the background of the invention, and thus may contain information that does not form the aforementioned techniques known to those skilled in the art.

Summary of invention

The present invention has been made in an effort to solve the above-mentioned problems related to the prior art as follows.

(i) removing or substantially reducing the induction period in the synthesis reaction.

(ii) continuously removing impurities which may contaminate the solvent in the reaction environment and act as a side reaction catalyst, as well as products of side reactions.

(iii) Synthesis of trialkoxysilane in a continuous mode.

In one aspect, the invention provides a method of preparing a trialkoxydecane, the method comprising: (a) pulverizing cerium (Si) in a solvent environment to particles having a particle size ranging from 30 to 100 μm, wherein the solvent Directly used as a solvent in the synthesis reaction of trialkoxysilane; (b) continuously supplied to the reactor and consumed during the synthesis An equal amount of hydrazine and an absolute alcohol suspension are continuously synthesized for the trialkoxy decane, and the consumption of the suspension is calculated according to the amount of the synthesized trialkoxysilane, using the following Equation 1, and thus supplied to the reactor as the The amount of lanthanum in the element of the suspension is equal to the number of lanthanum after the reaction in order to carry out a continuous and stable reaction: Equation 1 mSi=k1 ̇mTES+k2 ̇mTEOS

Wherein mTES is the mass of triethoxy decane, mTEOS is the mass of tetraethoxy decane collected from the direct reaction per unit hour, and k1 and k2 are respectively represented in the synthesis reaction of triethoxy decane and tetraethoxy decane. a coefficient of the molar ratio of the consumed enthalpy; and (c) continuously extracting the solvent from the reactor using a ceramic filter to remove impurities accumulated in the reactor while continuously supplying the same amount as the suspension as a suspension The solvent of the element of the liquid.

In the exemplary embodiment, the subject matter of the present invention can be achieved in the following manner.

In an exemplary embodiment, the linear dimension is in the range of 20 mm to 20 cm prior to comminution.

In another preferred embodiment, the catalyst required for the pulverization of ruthenium in a solvent environment is added directly to the ruthenium material.

In still another preferred embodiment, the amount of the catalyst, based on the amount of rhodium, may range from 1.0 to 10.0% by weight.

In still another preferred embodiment, the solvent in the synthesis reaction of the trialkoxide can be heated to 160 to 300 °C.

In another example specific example, in order to maintain the continuous mode, The ratio of the solvent and the stability of the catalyst is continuously stirred before being supplied to the reactor.

In another further preferred embodiment, the amount of rhodium, the solvent, and the amount of the catalyst in the reaction environment are constantly maintained throughout the synthesis reaction of the trialkoxide.

In still another further preferred embodiment, the extraction of the solvent containing the impurities generated during the reaction is carried out using a ceramic filter disposed on the main body of the reactor.

In still another exemplary embodiment, the ceramic film may have a pore size in the range of 1 to 10 μm.

In yet another further exemplary embodiment, the solvent used in the extraction can be used in the process by purification.

Other aspects and preferred embodiments of the invention are discussed below.

The above and other features of the present invention are discussed below.

As described above, according to the present invention, in the preparation of the raw material, the crucible as a raw material is pulverized in a solvent atmosphere which is not exposed to the air to suppress the formation of the oxide layer on the surface of the crucible, and to activate the reaction. Therefore, the method is economically comparable to the prior art because the total process time is greatly reduced and the yield is maximized by reducing the induction period in the early stages of the reaction of the hydrazine with the alcohol.

Further, the method can be simplified by the solvent used in the pulverization of ruthenium, and also for the synthesis reaction to be carried out later, and the method can be continuously carried out by continuously providing the suspension consumed in the synthesis reaction.

In addition, this method ensures the stability of the ruthenium particles because of the wet type The method of pulverizing ruthenium suppresses the explosion when the fine dust is generated in contact with oxygen in the air, and the method is economical because the solvent is continuously removed from the reaction environment by extracting the solvent by using a ceramic filter. Impurities, such that the conversion rate of the helium in continuous mode is maintained at a high level without the need for additional processes.

Therefore, according to the process for preparing a trialkoxysilane of the present invention, the yield of the trialkoxysilane and the economic benefit of the synthesis of the trialkoxysilane can be maximized because the total process time can be greatly reduced by reducing the induction period of the synthesis reaction. And the dialoxane can be continuously produced by continuously removing impurities.

Simple illustration

The above and other features of the present invention will now be described in detail with reference to certain exemplary embodiments thereof and the accompanying drawings, which are by way of illustration only. The graphs illustrating the yields of the products (triethoxyoxane (TES)) prepared in Examples 1 to 3 and Comparative Examples versus time are exemplified.

It is understood that the appended drawings are not necessarily to scale, The particular design features of the invention disclosed herein, including, for example, the specified dimensions, orientation, location, and shape, will be determined in part by the particular intended application and the environment in which it is used.

Detailed description

Hereinafter, various specific examples of the invention will be described in detail for reference, examples of which are illustrated in the accompanying drawings and Bright. The invention will be described in conjunction with the exemplary embodiments, and it is understood that this description is not intended to limit the invention to the exemplary embodiments. Rather, the invention is not intended to be limited to the details of the invention, and the various alternatives, modifications, equivalents, and other specific examples within the scope of the inventive concept as defined by the appended claims.

The present invention provides a method of preparing a trialkoxy decane comprising pulverizing a ruthenium in a solvent environment which is not exposed to air, causing the pulverized ruthenium to interact with absolute alcohol, removing impurities, and supplementing by equalizing The amount of raw material consumed activates the reaction mass. The trialkoxysilane can be synthesized by the following sequential steps.

(a) in a liquid environment, preferably in a solvent environment, pulverizing cerium into particles having a particle size ranging from 30 to 100 μm, and the liquid (or solvent) can be directly used for the synthesis of a trialkoxide, which will thereafter As a reaction solvent. Very importantly, in view of the fact that the reaction solvent can be used later, the pulverization of the crucible is carried out in a liquid environment, preferably in a solvent environment.

(b) The suspension of the hydrazine and the solvent, which is equal to the amount consumed during the synthesis, is continuously supplied to the reactor to synthesize the trialkoxide. In this respect, the amount of rhenium supplied to the reactor as an element of the suspension is equal to the amount of rhodium consumed by the reaction in order to carry out a sustained and stable reaction. In this regard, the consumption and supply of the suspension was calculated from the amount of the synthesized trialkoxysilane using Equation 1.

(c) The solvent is continuously withdrawn from the reactor using a ceramic filter to remove impurities accumulated in the reactor while continuously supplying the same amount of solvent as the extract as an element of the suspension.

According to a specific example of the present invention, a trialkoxysilane represented by the following formula I can be produced.

Formula 1 SiH(OR) ₃

In Formula 1, R is a C ₁ -C ₃ methyl, ethyl, propyl or isopropyl group.

According to the physical basis of the prior art example, in the first stage of activating the reagent, the lanthanum as a raw material is pulverized in a solvent environment, not in the air as in the prior art, so that it can be prevented on the surface of the pulverized ruthenium particles. Form a natural oxide. The oxide layer is inevitably formed on the surface of all metal ruthenium which is in contact with oxygen in the air. This oxidation reaction will occur at all temperatures, including room temperature, regardless of the purity of the ruthenium, i.e., in the case of all of the ruthenium ruthenium disclosed in the prior art.

At the same time, the natural oxide layer on the surface of the pulverized cerium particles has a technical problem of preventing the interaction between hydrazine and alcohol, that is, causing the reaction 'induction period'; the reference [1] discloses that the pulverization needs to be heated. A mixture of ruthenium and a catalyst; unreacted ruthenium due to incomplete reaction; and an additional halide catalyst to be used as disclosed in reference [1], or reference [26] discloses the return of the concentrated mixture to a reaction mass. As a result, technology and equipment have become complicated.

These disadvantages can be ruled out according to the methods of the present specific examples, since the lanthanide is pulverized in a liquid, i.e., in a solvent environment, without being exposed to air, so that an oxide layer is not formed on the surface of the pulverized cerium particles. That is, the ruthenium particles have an active surface. This is because the surface is not in contact with air, and it is not oxidized by contact with the solvent. The solvent can be used continuously after the main technical process chemical reaction. Thus, according to the present specific example, since the formation of an oxide layer on the surface of the cerium particles is suppressed at an early stage of the reaction, the reagents used in the main technical processes have been activated to immediately synthesize the trialkoxysilane. .

Further, the particle diameter of the fine particles pulverized by the method according to the present specific example may be in the range of 30 to 100 μm, which is smaller than the size of the particles disclosed in References [1] and [26] by about 10 times, and thus The contact area of the reagent is increased to rapidly reduce the induction period. On the other hand, if the lanthanide is pulverized into this size in air using the method disclosed in the reference [1] or [26], the induction period will increase because the particle size of the ruthenium after pulverization is reduced, 矽The total surface area increases, and the oxide layer naturally forms on the surface of the crucible; and other worse disadvantages.

The main disadvantages of the method disclosed in reference [26] include the need to concentrate the reaction mixture several times due to the newly added reagent in the unreacted hydrazine, the need to periodically withdraw the sediment into the suspension, and the precipitation for a long period of time. . According to the present specific example, these disadvantages are eliminated by performing the operation in the continuous mode. In this regard, according to the present specific example, in order to prevent removal of large reactive cerium particles from the reactor, a method of withdrawing the suspension through a ceramic filter is used. The amount of rhodium supplied as an element of the suspension to the reactor is maintained to be the same as the amount of rhodium involved in the reaction, and the amount participating in the reaction is the amount of the synthesized trialxane and the amount of hydrogen produced by the reaction. Decide. The solvent is continuously withdrawn through the outlet of the reactor, the impurities in the reactants are removed, and the same amount of solvent is added to the reactor as an element of the suspension.

The linear size of the crucible before pulverization is equal to or greater than 20 mm, preferably in the range of 20 mm to 20 cm, so that particles having a large amount of oxide on the surface thereof are prevented from being added to the reaction mixture.

According to the present specific example, the catalyst is added to the ruthenium material before the ruthenium pulverization, and the characteristics obtained are as follows. First, the two materials are comminuted to the same size. Second, when the pulverization is completed, the materials are uniformly mixed in the suspension in the solvent environment. The pore size of the ceramic filter can be in the range of 1 to 10 μm. If the pore size of the ceramic filter is less than 1 μm, the filtration process cannot be properly performed. On the other hand, if the pore size of the ceramic filter is larger than 10 μm, the reactive ruthenium particles are removed via the filter, so the loss of ruthenium is increased. If the initial particle size of the ruthenium particles is in the range of 30 to 100 μm, the suitable pore diameter of the ceramic filter is 5 μm. In this case, the total loss is less than 0.5%.

The method of the present specific example is carried out in the following manner. For example, using a hammer mill (from particle size to 1 mm) and a general planetary ball mill, the original crucible, which is a metal crucible having a purity of 98 to 99%, is pulverized into a desired particle size, wherein The reactor is filled with solvent. The solvent functions as a heat transfer oil, the examples of the solvent-based alkyl benzenes, alkyl naphthalenes and polyaromatic oils, preferably Reference [26] In the disclosed THERMINOL ^® 66 or other polyaromatic oil and the like. According to the present specific example, ruthenium is pulverized in a solvent environment into fine particles having a particle diameter ranging from 30 to 100 μm, and the interaction between hydrazine and alcohol is continuously carried out by continuously supplying a suspension to the reactor by using a digital metering pump. Here, the ruthenium particles are not separated from the solvent. Thereafter, a contact substance having a desired ability and a composition ratio is formed in the reactor.

According to the present specific example, the composition ratio of the suspension supplied for maintaining the continuous reaction (equal to the amount consumed during the synthesis) is arranged by the amount of hydrazine, and the amount of the hydrazine is determined by using Equation 1, from the synthesized trialkoxy The amount of decane is calculated. Thereafter, a suspension composed of hydrazine, the solvent and the catalyst is continuously and stably added to the reaction.

Examples of absolute alcohols used herein include absolute or absolute methanol known in the art. Further, examples of the catalyst include a copper-containing catalyst such as copper chloride (CuCl).

The main process is carried out in a high boiling solvent environment such as THERMINOL ^® 59, THERMINOL ^® 60, THERMINOL ^® 66, DOWTHERM ^® HT, MARLOTHERM ^® S, MARLOTHERM ^® or other polyaromatic oils as described above, from 180 to 260 °C, the same temperature range as described in reference [26]. In other words, the core of the main technical process involves filling the reactor with a suspension (including a catalyst that adds ruthenium, such as ruthenium in a solvent such as the solvent THERMINOL ^® 66, and copper chloride (CuCl) powder), and then After heating the mixture to 180 to 260 ° C, an alcohol such as ethanol or methanol is added to the reactor while vigorously stirring the mixture. The vapor-gas mixture and liquid thus formed are continuously removed from the reactor, and the product is separated using methods well known in the art including those disclosed in references [1] and [26] and the like. The standard material triethoxy decane or trimethoxy decane is separated by a conventional method.

According to the present specific example, the solvent is continuously extracted using a ceramic filter, and particularly because the pulverization method of ruthenium is different, the induction period is greatly reduced.

Thus, since tantalum is pulverized in the air in the prior art, the oxide layer is naturally formed on the surface of the crucible. Therefore, one of the important factors in the synthesis reaction of trialkoxysilane is naturally occurring, that is, during the induction period, when the additional raw material is supplied by withdrawing the suspension in a continuous process, the induction period is required. According to the present specific example, the induction during the early stages of the synthesis of the trialkoxide can be removed and reduced, and the impurities can be continuously removed by using a ceramic filter in a continuous process.

Meanwhile, according to the present specific example, when only the operations (a) described above and other operations disclosed in the prior art are used, the efficiency of the process is greatly improved without the operations (b) and (c). When operations (a) and (b) are used without operation (c), the efficiency of the process is also improved. Therefore, it is also understood that the process of not including operation (b) or operations (b) and (c) may be another invention having improved efficiency.

example

The following examples are illustrative of the invention but are not intended to limit the invention.

An example of the method of the present invention is based on experimental results obtained using equipment specially developed for the synthesis of trialkoxysilane.

Example 1

Triethoxyoxane was prepared in a 9 L reactor comprising electrothermal control devices of the same capacity and an impeller agitator with 4 wings and a rotational speed controlled in the range of 300 to 1500 rpm. Using a planetary grinder, 3.3 kg of metal ruthenium was pulverized into particles having a particle diameter ranging from 30 to 100 μm in a 6.6 kg solvent (THERMINOL ^® 66). In the pulverization process, 0.2 kg of copper chloride (CuCl) as a catalyst was added to the suspension. When the stirrer was continuously operated at 850 rpm, the contact material was heated to 242 + 2 ° C, and then dried in the reactor at a rate of 600 ml / hour using a digital metering pump (GRUNDFOS ^® DME 60-10 AR). Ethanol. Samples were collected from the reactor at the point in time when the liquid product was produced and every 30 minutes thereafter. The analysis results of the samples using Agilent ^® GC7890A of gas chromatography analysis, the synthesis reaction started after alcohol was added to the reactor, the reaction rate begins to increase after 60 minutes. The reaction rate of the synthesis of triethoxyoxane decreased from 180 minutes after the start of the reaction, and since the supply of alcohol began to slow down from 260 minutes. Thus, 1635 g of triethoxy decane and 105 g of tetraethoxy decane were obtained. The selectivity to triethoxy decane was 94%.

Comparative example

The experiment was carried out in the same manner as in Example 1, except that the method of preparing the reagent was different. Using a planetary grinder, the crucible is pulverized in air to particles having a particle size ranging from 30 to 100 μm. The milled silicon 3.3kg, 6.6kg as the solvent 0.2kg THERMINOL ^® 66 and a copper (of CuCl) chloride was added to the catalyst in the reactor to initiate the reaction. Referring to the analysis of the sample, the reaction between the metal ruthenium and the alcohol started 150 minutes after the supply of the alcohol, after which the reaction rate was greatly increased. The synthesis of triethoxydecane slowed down 500 minutes after the alcohol was supplied. At this 500 minutes, 1435 g of triethoxy decane and 614 g of tetraethoxy decane were obtained. The selectivity to triethoxy decane is 70%.

Example 2

The experiment was carried out in the same manner as in Example 1, except that the same enthalpy of consumption as hydrazine was continuously supplied to the reactor, so that in the reaction with absolute ethanol, the mass ratio of the solvent to hydrazine in the suspension was 2:1. In the trialkyloxane In terms of synthesis, the element as a suspension is supplied to the reactor at the same rate as the hydrazine consumption. The number of enthalpy consumed per unit hour is calculated according to the reaction mass balance using the following equation.

Equation 1 mSi=k1 ̇mTES+k2 ̇mTEOS

Here, the mass of mTES is triethoxy decane, the mass of mTEOS is tetraethoxy decane (collected from the direct reaction per unit hour), and the k1 and k2 systems respectively mean triethoxy decane and tetraethoxy decane. The coefficient of the molar ratio of enthalpy consumed in the synthesis. In Example 2, k1 = 0.171 was identified and k2 = 0.135. Thus, using the amount calculated by the above Equation 1, the enthalpy as an element of the suspension was continuously added to the reactor. Simultaneously, the solvent was continuously withdrawn from the reactor through a ceramic filter installed in the reactor body. A solvent including impurities is collected into a recovery container. A vacuum was formed behind the ceramic filter by applying 10 mbar, and unreacted ruthenium and a catalyst were filtered off to discharge the solvent. In this regard, the solvent is continuously withdrawn from the reactor through the ceramic filter, and the amount of solvent discharged is twice the mSi provided by Equation 1, and is equal to the amount added to the reactor as a suspension element. Accordingly, the composition of the contact material can be maintained constant, and the level of composition in the reactor can be maintained constant. Every 3 hours, the sample in the reactor is withdrawn to control the composition of the contact material. The level of the contact material in the reactor is visually determined through the window of the reactor. The synthesis of triethoxyoxane started 10 minutes after the supply of the alcohol to the reactor, and the reaction rate increased rapidly at the beginning of 60 minutes, and greatly increased from this to 120 minutes, when the production rate of the trialkoxide was 420. Stable at 450 g/h. In 500 minutes, the suspension containing 600g of silica, and the solvent is continuously supplied as 1200g of THERMINOL ^® 66. Within 500 minutes, 3380 g of triethoxy decane and 141 g of tetraethoxy decane were obtained. The selectivity to triethoxysilane is 96%.

Example 3

The experiment was carried out in the same manner as in Example 2, in which Equation 1 was used to calculate the amount of hydrazine consumed in the reaction of hydrazine with absolute alcohol, and the hydrazine was continuously supplied to the reactor, so that the mass ratio of the solvent to hydrazine in the suspension was 2:1, but no ceramic filter was installed and no solvent was withdrawn. The synthesis of triethoxyoxane started 9 minutes after the supply of the alcohol to the reactor, and the reaction rate increased rapidly at the first 90 minutes and then stabilized at a yield of 400 g/h of the trialkoxide. After 250 minutes of alcohol supply, the reaction was terminated by a large amount of bubble generation. During this time, in the reactor was continuously added 290g and 580g of the silica suspension as a catalyst THERMINOL ^® 66. Due to the newly added solvent, the amount of contact material in the reactor increases, thus generating bubbles. During 250 minutes, 1600 g of triethoxyoxane and 120 g of tetraethoxyoxane were obtained. The selectivity to triethoxy decane was 93%.

Table 1 below shows the results of Examples 1 to 3 and Comparative Examples.

As described above, according to the method of the present specific example, the crucible is pulverized in a liquid environment to prevent the formation of an oxide layer on the surface of the crucible, and the reactivity is stable in the process (Examples 1, 2, and 3), so that the induction period The early stages of the reaction between hydrazine and alcohol are greatly reduced. Therefore, the process time can be reduced and the yield can be increased, so the process is economical.

In addition, when the suspension was added (Examples 2 and 3), the increase in TES yield, the increase in TES selectivity, and the induction period during the early stages of the reaction were reduced as compared with the comparative examples. When the extraction process was further carried out (Example 2), the TES yield was increased more than twice as compared with the comparative example during the same reaction period.

The method according to the invention can be carried out simply by using equipment which is generally applicable. Since the preparation of the raw material (pulverization of ruthenium) is carried out in a solvent environment as a reaction solvent of the method, the process is simplified.

Since the synthesis method is continuously carried out by continuously supplying the suspension consumed during the synthesis and continuously removing the impurities using the ceramic filter, the total process time is greatly reduced, and the trialkoxysilane is continuously produced, Both yield and economic benefits can be maximized.

The method according to the present invention provides the following effects: - reduction in induction time of synthesis; - continuous synthesis of trialkoxysilane; and - extraction of solvent using a ceramic filter to continuously remove impurities from the reaction environment.

According to the method provided by the present invention, all problems can be solved.

The invention has been described in detail with reference to preferred embodiments. However, those skilled in the art can appreciate that the theory and thoughts of the present invention are not lost. In the event that the changes are made in the specifics, the scope of which is defined by the accompanying patent application and the equivalents.

Fig. 1 is a graph showing the yield versus time of the products (triethoxyoxane (TES)) obtained in Examples 1 to 3 and Comparative Examples.

Claims (12)

A method for preparing a trialkoxy decane, comprising: (a) pulverizing cerium (Si) to a particle having a particle diameter ranging from 30 to 100 μm in a solvent environment not in contact with air, wherein the solvent is directly used as a trialkoxy group a solvent in the synthesis reaction of decane; (b) continuously supplying a suspension of hydrazine and absolute alcohol in an amount equal to the amount consumed during the synthesis in the reactor, continuously synthesizing the trialkoxide, using Equation 1 below, in accordance with The amount of the synthesized trialkoxysilane, the consumption of the suspension is calculated, and the amount of rhodium which is supplied to the reactor as an element of the suspension is equal to the amount of rhodium after the reaction for continuous and stable reaction. : Equation 1 mSi=k1 ̇mTAS+k2 ̇mTAOS where mSi is consumed per unit time, mTAS is the mass of the trialkoxide, and mTAOS is the mass of the tetraalkyloxane obtained by direct reaction per unit hour. K1 and k2 are the molar ratios of rhodium consumed in the synthesis procedure of the trialkoxide and the tetraalkane, respectively; and (c) continuously extracting the solvent from the reactor using a ceramic filter, and removing the accumulated The impurities in the reactor, while continuously feeding the same amount as the extraction solvent of the elements of the suspension. A method of producing a trialkoxysilane according to the first aspect of the invention, wherein the linear size of the crucible is in the range of 20 mm to 20 cm before the pulverization. A method for producing a trialkoxysilane according to the first aspect of the invention, wherein the solvent to rhodium mass ratio is in the range of 1:2 to 2:1. A method for producing a trialkoxysilane according to the first aspect of the invention, wherein 1.0 to 10.0% by weight of the catalyst is directly added to the crucible in which the pulverization procedure is carried out in a solvent environment. A method of producing a trialkoxysilane according to the first aspect of the invention, wherein the catalyst is a copper-containing catalyst. A process for producing a trialkoxysilane according to the first aspect of the invention, wherein in the synthesis reaction of the trialkoxide, the solvent is heated to 160 to 300 °C. A process for the preparation of a trialkoxysilane according to the first aspect of the invention, wherein the operations (a), (b) and (c) are carried out successively, while the copper-containing catalyst, and absolute or absolute ethanol are used in the pulverization of the crucible The solvent is heated to 160 to 300 ° C for use as the absolute alcohol and in a continuous synthesis reaction of a trialkoxide. A method of producing a trialkoxysilane according to the first aspect of the invention, wherein the suspension is continuously stirred before being supplied to the reactor in order to maintain the stability ratio of the hydrazine, the solvent and the catalyst. A method for producing a trialkoxysilane according to the first aspect of the invention, wherein the extraction of the solvent for removing impurities dissolved in the solvent is carried out using a ceramic filter installed in a main body of the reactor. A method of producing a trialkoxysilane according to the first aspect of the invention, wherein the ceramic membrane has a pore diameter in the range of 1 to 10 μm. The method for producing a trialkoxysilane according to the first aspect of the invention, wherein in the entire synthesis reaction of the trialkoxide, the amount of the rhodium, the solvent and the catalyst in the reaction environment are constantly maintained. A method for producing a trialkoxysilane according to the first aspect of the invention, wherein the trialkoxysilane is represented by the following formula 1: wherein: SiH(OR) ₃ wherein R is a C ₁ -C ₃ methyl group, an ethyl group, a propyl group Or an isopropyl group.