- Analysis of the pyrolysis products of dimethyldichlorosilane in the chemical vapor deposition of silicon carbide in argon
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A study of the products and reactions occurring during the chemical vapor deposition of silicon carbide from dimethyldichlorosilane in argon is presented. The silicon carbide solid that formed showed the presence of hydrogen and chlorine as impurities, wh
- Cagliostro,Riccitiello,Carswell
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- Amorphous silicon: New insights into an old material
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Amorphous silicon is synthesized by treating the tetrahalosilanes SiX4 (X=Cl, F) with molten sodium in high boiling polar and non-polar solvents such as diglyme or nonane to give a brown or a black solid showing different reactivities towards suitable reagents. With regards to their technical relevance, their stability towards oxygen, air, moisture, chlorine-containing reaction partners RCl (R=H, Cl, Me) and alcohols is investigated. In particular, reactions with methanol are a versatile tool to deliver important products. Besides tetramethoxysilane formation, methanolysis of silicon releases hydrogen gas under ambient conditions and is thus suitable for a decentralized hydrogen production; competitive insertion into the MeO-H versus the Me-OH bond either yields H- and/or methyl-substituted methoxy functional silanes. Moreover, compounds, such as MenSi(OMe)4-n (n=0-3) are simply accessible in more than 75% yield from thermolysis of, for example, tetramethoxysilane over molten sodium. Based on our systematic investigations we identified reaction conditions to produce the methoxysilanes MenSi(OMe)4-n in excellent (n=0:100%) to acceptable yields (n=1:51%; n=2:27%); the yield of HSi(OMe)3 is about 85%. Thus, the methoxysilanes formed might possibly open the door for future routes to silicon-based products. Amorphous silicon is easily synthesized from tetrahalosilanes SiX4 (X=Cl, F) and molten sodium in different solvents. Reactivity studies prove the resulting materials as versatile tools for the formation of technical important silanes, such as the silicon chloro-, alkoxy-, and methylalkoxy-substituted derivatives (see figure; bl=black, br=brown).
- Spomer, Natalie,Holl, Sven,Zherlitsyna, Larissa,Maysamy, Fariba,Frost, Andreas,Auner, Norbert
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- Preparation of trichlorosilane from hydrogenation of silicon tetrachloride in thermal plasma
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A new method of producing trichlorosilane by hydrogenation of silicon tetrachloride with assistance of DC charged thermo-plasma was proposed. We have studied the dependence of degree of disassociation and ionization of hydrogen on temperature, as well as
- Wu, Qingyou,Chen, Hanbin,Li, Yuliang,Tao, Xumei,Huang, Zhijun,Shang, Shuyong,Yin, Yongxiang,Dai, Xiaoyan
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- Yolk-Shell-Structured CuO?ZnO?In2O3 Trimetallic Oxide Mesocrystal Microspheres as an Efficient Catalyst for Trichlorosilane Production
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Trichlorosilane (TCS), the primary chemical feedstock for production of high-purity Si used in Si-based solar cells, is currently manufactured industrially via a non-catalytic hydrochlorination of metallurgical Si. This process generates a huge amount of undesirable silicon tetrachloride (STC) byproduct. Here we report the synthesis of yolk-shell-structured CuO?ZnO?In2O3 trimetallic oxide mesocrystal microspheres that can be employed as an efficient catalyst to produce TCS catalytically. The CuO?ZnO?In2O3 microspheres with multiple hetero-interfaces were prepared using a facile solvothermal reaction followed by calcination. We found that differing from a single CuO mesocrystal, the electronic density on Cu atoms in the CuO phase within CuO?ZnO and CuO?ZnO?In2O3 can be tuned by varying the composition. When used as a catalyst for Si hydrochlorination reaction to produce TCS, CuO?ZnO?In2O3 shows excellent catalytic performance with very high Si conversion and TCS selectivity. Under the same reaction conditions, the TCS yield increased 13 times relative to the catalyst-free process. This work demonstrates the possibility to decrease the amount of STC needed for the catalytic manufacture of TCS, and provides an approach to the facile synthesis of multi-component mesocrystal materials with a specific structure.
- Guo, Xiangfeng,Ji, Yongjun,Jia, Lihua,Li, Jing,Li, Qiongguang,Li, Xin,Liu, Hezhi,Su, Fabing,Zhang, Yu,Zhong, Ziyi
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- Hydrodechlorination of silicon tetrachloride to trichlorosilane over ordered mesoporous carbon catalysts: Effect of pretreatment of oxygen and hydrochloric acid
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This paper reports on the catalytic reaction for the conversion of silicon tetrachloride (STC) to trichlorosilane (TCS) over pretreated ordered mesoporous carbon (OMC) catalysts by oxygen (denoted as OMC-O2) and hydrochloric acid (denoted as OM
- Kwak, Do-Hwan,Akhtar, M. Shaheer,Kim, Ji Man,Yang, O-Bong
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- REACTION OF 2,4,6-TRI-t-BUTYLPHENYLLITHIUM WITH BROMOTRICHLOROSILANE. GENERATION OF TRICHLOROSILYLLITHIUM, LiSiCl3
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Trichlorosilyllithium, LiSiCl3, is formed by reaction of bromotrichlorosilane with 2,4,6-tri-t-butylphenyllithium or mesityllithium.It is detected as trichlorosilane which is obtained by protonation and characterized by a 29Si NMR shift of 30.9 ppm.Its stability is evaluated.
- Oehme, H.,Weiss, H.
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- Formation of 1,1-dichloro-2-vinyl-1-silacyclopropane by a photoinduced reaction between dichlorosilylene and 1,3-butadiene
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A matrix FTIR study of interaction between SiCl2 and 1,3-butadiene revealed that at low temperatures, it stops at the step of complexation between the reactants. This allowed us to investigate a photochemical version of this interaction resulti
- Boganov, Sergey E.,Promyslov, Vladimir M.,Rynin, Stanislav S.,Krylova, Irina V.,Egorov, Mikhail P.
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- Compensation effect in trichlorosilane synthesis
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In a recent publication [J. Acker, K. Bohmhammel, J. Phys. Chem. B 106 (2002) 5105], the reactions between transition metal silicides and hydrogen chloride were studied by isothermal calorimetric measurements. The obtained apparent activation energies and pre-exponential factors show clearly a linear dependence that is attributed to the compensation effect. An isokinetic temperature of 696.9±22.1 K was determined. According to Larsson's model of selective energy transfer, a characteristic frequency of 969.3±46.5 cm-1 is calculated. The occurrence of the compensation effect is discussed in terms of chemisorption, precursor formation, and the involvement of surface species in essential reaction steps.
- Acker, J?rg,Bohmhammel, Klaus
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- Preparation of trichlorosilane by plasma hydrogenation of silicon tetrachloride
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We have studied silicon tetrachloride hydrogenation in an rf (40.68 MHz) plasma and have determined the trichlorosilane yield as a function of the molar energy input, H2: SiCl4 molar ratio, and pressure. The highest trichlorosilane y
- Gusev,Kornev,Sukhanov
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- The Amine Catalysed Cleavage of Oligochloropolysilanes with HCl
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Tetrakis(trichlorosilyl)silan (neo-Si3Cl12) is cleaved in an amine catalysed reaction by HCl in benzene solution to tris(trichlorosilyl)silan HSi(SiCl3)3 (1).The amine catalysed cleavage of 1 with different amines and solvents is investigated.A new method for preparation of pentachlorodisilane HSi2Cl5 is described and a reaction mechanism for the cleavage is postulated. - Keywords: Oligochlorosilanes; SiSi-Cleavage with HCl; neo-Dodecachloropentasilane; Tris(trichlorosilyl)silane
- Raml, Walter,Hengge, Edwin
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- Reaction of Si with HCl to form chlorosilanes time dependent nature and reaction model
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We propose a chemical vapor deposition (CVD) process with closed gas recycling for making low-cost, crystalline silicon thin films for solar cells, which connects chlorosilane synthesis from Si and HCl with Si thin-film growth by CVD from chlorosilanes. In this work we studied the formation of chlorosilanes by the reaction of Si with HCl at temperatures ranging from 623 to 723 K. The reaction rate is time dependent, and many pores are formed on the surface of particles after reaction. These pores are active sites for chemical reactions, and the reaction rates increase with increasing pore area. The rate can be correlated with the conversion ratio of Si, and the temporal evolution of the reaction rate can be explained by a reaction model called the shrinking-core model with growing pores. By using this model, we estimated the reaction rates per unit area of activated surfaces and converted them into a rate equation that can be used for the reactor design. The incubation time of the reaction can be shortened by pretreating the Si particles in a fluidized bed, which probably creates defects in the native oxide layers on the particles, which in turn become reactive sites.
- Noda, Suguru,Tanabe, Katsuaki,Yahiro, Takashi,Osawa, Toshio,Komiyama, Hiroshi
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- An experimental and theoretical study of spin-spin coupling in chlorosilanes
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An experimental and theoretical study of the absolute value of the one-bond spin-spin coupling constant |1J(Si,H)| in SiH nCl4-n (n = 0-4) dissolved in THF-d8 is presented. We found |1J(Si,H)| to increase with an increasing number of chlorine substituents, and the quantitative changes were found to differ from the values previously reported for the same compounds dissolved in cyclohexane-d12. We also report on the variations in | 1J(Si,H)| as a function of temperature, which we found to be linearly temperature dependent for the chlorine-substituted silanes and temperature independent for SiH4. Furthermore, the temperature dependence of |1J(Si,H)| varied between the different chlorosilanes. Solvent-solute interactions were studied by quantum chemical DFT calculations. The variations in chloro-silane bond lengths upon adduct formation and the different adduct interaction energies may explain the temperature dependences of the coupling constants.
- Thorshaug, Knut,Swang, Ole,Dahl, Ivar M.,Olafsen, Anja
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Bu3SnH is an effective reagent for partial conversion of Si-Cl into Si-H groups. The presented hydrogenation mechanism postulates the coordination of the catalyst (Lewis bases) or the solvent to silicon, giving an intermediate with higher coordinated silicon atom in the first step, followed by the attack of tributyltin hydride by a single electron transfer. This mechanism implies that the intermediate having a hypervalent silicon atom reacts more rapidly than the starting tetracoordinated silane.
- Paetzold,Roewer,Herzog
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- Reactivity of intermetallic compounds: A solid state approach to direct reactions of silicon
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The present work is focused on a new approach to describe, quantify, and compare the reactivity of various transition metal silicide phases toward hydrogen chloride. Thermodynamic and kinetic parameters are obtained from isothermal calorimetric studies of these reactions. The reactivity of the silicide phases is discussed in terms of reaction start temperatures, rate constants, and apparent activation energies. Negative apparent activation energies are observed at low temperatures and are attributed to an initial stage of reaction where chlorine is chemisorbed and then incorporated into the silicide lattice near the surface. At a later time, a chlorine-containing reaction layer is formed having a composition and reactivity remarkably different from that of the bulk phase. On the basis of solid-state investigations, a diffusion model of the microscopic structure of these layers is presented, where a displacement of nickel atoms occurs followed by the occupation of nickel sites by chlorine. A model is suggested in which the electron level of the reaction layer is adjusted by the chlorine content of this layer, resulting in a electronic stabilization of silylenoide species at the surface. The model is applied to explain product distribution in the induction period during the direct reaction of silicon and methyl chloride.
- Acker, Joì?rg,Bohmhammel, Klaus
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- Direct synthesis of tris(chlorosilyl)methanes containing Si-H bonds
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Direct reaction of elemental silicon with a mixture of chloroform and hydrogen chloride has been studied in the presence of a copper catalyst using a stirred reactor equipped with a spiral band agitator at various temperatures from 280 to 340 °C. Tris(chlorosilyl)methanes 1a-e with Si-H bonds were obtained as the major products along with byproducts of bis(chlorosilyl)methanes, derived from the reaction of silicon with methylene chloride formed by the decomposition of chloroform, and trichlorosilane and tetrachlorosilane produced from the reaction of elemental silicon with hydrogen chloride. The decomposition of chloroform was suppressed and the production of polymeric carbosilanes reduced by adding hydrogen chloride to chloroform. The deactivation problem of elemental silicon due to the decomposition of chloroform and polycarbosilanes was eliminated. Cadmium was a good promoter for the reaction, while zinc was found to be an inhibitor for this particular reaction.
- Han, Joon Soo,Yeon, Seung Ho,Yoo, Bok Ryul,Jung, Il Nam
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- Infrared Laser Photochemistry of SiH4-HCl Mixtures
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The infrared laser photochemistry of SiH4-HCl mixtures has been studied in a pressure range of 28-60 torr and in a temperature range of 295-414 K.The gaseous products observed are H2, Si2H6, SiH3Cl, SiH2Cl2, and SiHCl3 with trace amounts of Si3H8 and Si2H5Cl.As is usual in silane decompositions, a solid product containing silicon, hydrogen, and perhaps very small amounts of chlorine was also formed.The photochemical conversion is best described by initial decomposition of SiH4 to SiH2 and H2 followed by competition of SiH4 and HCl for SiH2 molecules.The simultaneous formation of all chlorosilanes suggests that decomposition of the initial product of SiH2-HCl reaction leads in turn to SiHCl and SiCl2 molecules.Studies of the temperature dependence of the rates of the competing reactions indicate that the activation energy for insertion of SiH2 into HCl is less than 1.3 kcal/mol.
- Moore, C. B.,Biedrzycki, J.,Lampe, F. W.
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- METHOD FOR THE DEHYDROGENATION OF DICHLOROSILANE
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Dichlorosilane and trichlorosilane are dehydrogenated at elevated temperature in the presence of an ammonium or phosphonium salt as a catalyst, and a halogenated hydrocarbon or hydrogen halide. The method may be used to synthesize organochlorosilane.
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Paragraph 0102; 0103
(2021/06/22)
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- New vinyl alkoxy silane preparation process
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The present invention discloses a new vinyl alkoxy silane preparation process, which is characterized in that hydrogen chloride produced during a preparation process is adopted as a reactant to synthesize an initial raw material trichlorosilane, the hydrogen chloride is recycled, and the byproduct bis(trialkoxy)silyl ethane is adopted as a reaction solvent during a hydrogen silicon addition process, such that the byproduct emission is reduced, the new impurity introduction is avoided, and the product purity is improved. According to the present invention, the new process has characteristics of stable production, simple preparation process, and mild reaction conditions, and the yield of the product vinyl alkoxy silane is high, and the product purity is more than 99%.
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Paragraph 0041; 0042
(2016/10/08)
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- METHOD FOR HYDROGENATING SILANE COMPOUND
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In the present invention, provided is a method for hydrogenating silane compounds, comprising the steps of supplying hydrogen to a low-temperature plasma reaction apparatus and accordingly generating low-temperature plasmas including hydrogen ions, electrons and hydrogen atom radicals; supplying raw materials including the silane compound to the low-temperature plasma reaction apparatus; and making the silane compound, the hydrogen ion, the electrons and the hydrogen atom radical have the hydrogenating reaction.
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Paragraph 0086 - 0095
(2016/12/12)
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- METHOD FOR PREPARING A HALOSILANE
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A method for preparing a reaction product includes separate and consecutive step (1) and step (2), where: step (1) is contacting, at a temperature from 200 °C to 1400 °C, an ingredient including a silane of formula HaRbSiX(4-a-b), where subscript a is 0 to 4, subscript b is 0 or 1, a quantity (a + b) ≤ 4, each R is independently a monovalent organic group, and each X is independently a halogen atom, with the proviso that when the quantity (a + b) 2; with a copper catalyst; thereby forming a reactant; and step (2) is contacting the reactant with an organohalide at a temperature from 100 °C to 600 °C; thereby forming the reaction product and a spent reactant. The reaction product is distinct from the silane used in step (1), and the reaction product includes a halosilane of formula R2S1X2, where each R is independently a monovalent organic group, and each X is independently a halogen atom.
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Paragraph 0058
(2014/10/03)
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- PROCESS FOR THE PRODUCTION OF SILANE PRODUCTS FROM CALCIUM SILICIDE
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A process for preparing a reaction product including a silane product includes step (i), (ii), and (iii). Step (i) is contacting an organohalide with a calcium silicide at a temperature from 300 °C to 700 °C to form the reaction product including a spent reactant and the silane product. The silane product has formula RmHnSiX(4-m-n), where each R is independently a monovalent organic group, each X is independently a halogen atom; subscript m is 0 to 4; subscript n is 0 to 2; and a quantity (m + n) is 0 to 4. Step (ii) is contacting, at a temperature from 200 °C to 1400 °C, the spent reactant with a silane of formula HaRbSiX(4-a-b), where subscript a is 0 to 4, subscript b is 0 or 1, a quantity (a + b) ≤ 4. The silane of formula HaRbSiX(4-a-b) is distinct from the silane product of formula RmHnSiX(4-m-n). When the quantity (a + b) 2; thereby forming a reactant. Step (iii) is contacting the reactant formed in step (ii) with an additional organohalide at a temperature from 300 °C to 700 °C to form an additional silane product of formula RmHnSiX(4-m-n). Steps (ii) and (iii) are performed separately and consecutively after step (i).
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Paragraph 0052
(2014/11/11)
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- PROCESS FOR SELECTIVE PRODUCTION OF HALOSILANES FROM SILICON-CONTAINING TERNARY INTERMETALLIC COMPOUNDS
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A process includes contacting an organohalide with a ternary intermetallic compound at a temperature of 300 °C to 700 °C to form a reaction product including a halosilane. The ternary intermetallic compound includes three metals. The first metal is Cu or Mg; the second metal is Au, Ni, or Pd; and the third metal is Si.
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Paragraph 0043
(2014/08/06)
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- METHOD OF PREPARING HALOGENATED SILAHYDROCARBYLENES
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A method comprises separate and consecutive steps (i) and (ii). Step (i) includes contacting a copper catalyst with hydrogen gas and a halogenated silane monomer at a temperature of 500 °C to 1400 °C to form a silicon-containing copper catalyst comprising at least 0.1 % (w/w) of silicon. Step (ii) includes contacting the silicon-containing copper catalyst with an organohalide at a temperature of 100°C to 600 °C to form a reaction product. The organohalide has formula HaCbXc, where X is a halogen atom, subscript a is an integer of 0 or more, subscript b is an integer of 1 or more, and subscript c is an integer of 2 or more. The method produces a reaction product. The reaction product includes a halogenated silahydrocarbylene.
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Paragraph 0039
(2014/05/07)
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- Catalyst for hydrodechlorination of chlorosilanes to hydrogen silanes and method for implementing hydrogen silanes using said catalyst
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The invention relates to a method for producing hydrogen silanes of general formula RnCl3-nSiH by converting chlorosilanes of general formula RnCl4-nSi, where R, in both formulas simultaneously and independently of each other, is a hydrogen atom, an optionally substituted or unsubstituted hydrocarbon radical having 1 to 18 carbon atoms, and n can have the value of 1-3, and hydrogen gas in the presence of a catalytic quantity (K): zinc and/or an alloy comprising zinc on a metal oxide carrier.
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Page/Page column 2
(2012/06/18)
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- METHOD OF MAKING A TRIHALOSILANE
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A method of making a trihalosilane comprising contacting an organotrihalosilane according to the formula RS1X3 (I), wherein R is C1-C10 hydrocarbyl and each X independently is halo, with hydrogen, wherein the mole ratio of the organotrihalosilane to hydrogen is from 0.009:1 to 1:2300, in the presence of a catalyst comprising a metal selected from (i) Re, (ii) a mixture comprising Re and at least one element selected from Pd, Ru, Mn, Cu, and Rh, (iii) a mixture comprising Ir and at least one element selected from Pd and Rh, (iv) Mn, (v) a mixture comprising Mn and Rh, (vi) Ag, (vii) Mg, and (viii) Rh at from 300 to 800 °C to form a trihalosilane.
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Page/Page column 22-23
(2012/06/30)
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- PROCESS FOR RECOVERY OF HIGH BOILING WASTE
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Waste streams from different chloromonosilane production processes are combined and reacted in a single recovery process. Useful monosilane species may be obtained with a single recovery process.
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Page/Page column 9
(2010/08/08)
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- Process and apparatus for the hydrogenation of chlorosilanes
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Hydrogenation of a chlorosilane takes place in a reactor having a graphite reaction chamber with a surface which contacts the chlorosilane and a graphite electric heating element which also contacts the chlorosilane, wherein an Si-containing compound and
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Page/Page column 4
(2008/06/13)
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- Method for the production of hsicl3 by catalytic hydrodehalogenation of sicl4
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The invention relates to a process for the catalytic hydrodehalogenation of SiCl4 to form HSiCl3, which comprises bringing a gaseous feed mixture comprising hydrogen and silicon tetrachloride into direct contact with at least one hea
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Page/Page column 2-3
(2008/06/13)
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- PROCESS FOR THE PRODUCTION OF HYDROCHLOROSILANES
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Hydrogen-containing chlorosilanes are prepared by reacting hydrogen with silicon tetrachloride and/or hydrogen chloride and silicon wherein the surface of the silicon has been modified by a chemical vapor deposition of one or more catalytic materials, suc
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Page/Page column 8
(2008/06/13)
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- Silane molecules with pre-activated and protein-resistant functionalities and silane films comprising such molecules
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The present invention provides a silane molecule which combines pre-activated and protein-resistant functionalities in one molecule; the molecule has a general formula: A-(CH2)n—(O[CH2]t)m—(CH2)v—Y??(1) wherein A is a functional group for binding to a substrate and Y is a functional group for binding to biomolecules. The invention furthermore provides a method for the synthesis of such a silane molecule and a method for depositing a monolayer of such silane molecules onto a substrate. Such a monolayer of silane molecules may be used in biosensors, DNA/protein micro-arrays or other sensor applications. For further lowering the protein binding to the surface of the biosensor, the monolayer may furthermore comprise second silane molecules with formula: B—(CH2)o—(OCH2CH2)r-Z??(4)
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- Reactions of Tetrachlorogermane with Allyl Chloride and Methallyl Chloride in the Presence of Hexachlorodisilane as an Initiator
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Allyl chloride and methallyl chloride react with tetrachlorogermane in the presence of hexachlorodisilane to give as major products allyltrichlorogermane and allyltrichlorosilane in the former case and (2-methyl-2-propenyl)trichlorogermane and (2-methyl-2-propenyl)trichlorosilane in the latter case. The reaction schemes are proposed and discussed.
- Chernyshev,Komalenkova,Yakovleva,Bykovchenko,Khromykh,Bochkarev
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p. 894 - 897
(2007/10/03)
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- Tris(silyl) alkanes and their preparation methods
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The present invention relates to a process for preparing tris(silyl)alkanes comprising directly reaction a mixture of organic compounds having a trichloromethyl group represented by formula I and hydrogen chloride or alkyl chlorides represented by formula II, with metallic silicon to give the tris(silyl)alkanes represented by formula III, IV, V and VI: STR1 wherein R represent independently hydrogen or methyl and R' represents hydrogen, alkyl(C1 -C4), or CH2 CH2 Cl.
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- Selective and sequential reduction of polyhalosilanes with alkyltin hydrides
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The reactions between alkyltin hydrides and a variety of polyhalo- and mixed halosilanes have been investigated. For SiCl4 and SiCl3H, the reductions proceed in a stepwise manner to yield the monoreduced species as the major products. The reduction of SiBr4 occurs much faster to yield a mixture of SiBr3H and SiH4, or, in the vapor phase, SiBr3H as the sole product. SiF3X (X = Br, Cl) is converted into SiF3H, with no further reduction of SiF3H observed upon addition of a second equivalent of alkyltin hydride. SiF2HX compounds (X = Br, Cl) are obtained from SiF2X2 and are converted into SiF2H2 with excess Me3SnH. Redistribution becomes competitive with reduction in reactions between Me3SnH and SiFBr3, leading to mixtures of SiH4, SiF2H2, and SiF3H. The major products in the reaction between SiCl2Br2 and Me3SnH are SiCl3H and SiH4 (no SiCl2H2 was observed). Several probable intermediates were independently synthesized and allowed to react with Me3SnH. Together with deuterium labeling experiments, these reactions shed light on the mechanisms involved in these systems. In particular, the reactions appear not to proceed via free radicals.
- D'Errico, John J.,Sharp, Kenneth G.
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p. 2177 - 2180
(2008/10/08)
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- Reaction of Magnesium Silicide and Silicon Tetrachloride/Trichlorosilane in Presence of Hydrogen
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The formation of silane (SiH4) has been observed during the reaction of silicon tetrachloride and hydrogen (SiCl4 + H2) with magnesium silicide (Mg2Si) at 400-500 deg C.The silane formed decomposes to give silicon in the vicinity of Mg2Si charge.A mixture of trichlorosilane + H2 reacts with Mg2Si at 250 deg C to afford silane which has been separated and decomposed to high purity silicon.The reaction of SiHCl3 + H2 with Mg2Si gives optimum conversion when SiHCl3:H2 ratio is 1:4 at the reaction temperature of 250 deg C.
- Mulla, I. S.,Choube, A. C.,Dongare, M. K.,Sinha, A. P. B.
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p. 756 - 758
(2007/10/02)
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- KINETIC FEATURES OF THE REACTION OF SILANE WITH CHLORINE AND NITROGEN TRICHLORIDE IN RAREFIED FLAMES.
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A new, branched-chain process has been found, the reaction of silane with nitrogen trichloride. It was established that the rate of reaction of SiH//4 with NCl//3 and Cl//2, the spectral composition, and the intensity of the chemiluminescence of the flame, as well as the dependence of the nature of these quantities on the initial pressure, undergo discontinuous changes when the ratio of the concentrations of the initial reactants is varied within the autoflammability region close to a particular value. Regimes of twofold inflammation of SiH//4 with Cl//2 and NCl//3 in a closed volume have been found: the flame of the two inflammations which follow one another in this regime changes color. This indicates a change in the mechanism of combustion.
- Azatyan,Markevich
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p. 1120 - 1126
(2008/10/08)
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- Process for the preparation of organoalkoxysilanes
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An improvement in a process for the esterification of a organochlorosilane by feeding alcohol into a chlorosilane maintained within a reaction zone without said alcohol contacting said chlorosilane in the gas phase wherein the esterification is performed stepwise with extraction of hydrogen chloride which has developed, the improvement which comprises employing in at least a final esterification step an organochlorosilane of the formula wherein R represents an optionally halogen-substituted alkyl radical which can also contain an oxygen or sulfur atom in the chain, or a halogen or a NO2 group or a protected phenolic group containing aryl radical, a equals 0, 1, or 2, b equals 1 or 2, and a+b amounts to a maximum of 3, said final esterification step being performed with the addition of heat.
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