WO2014113124A1

WO2014113124A1 - Process for selective production of halosilanes from silicon-containing ternary intermetallic compounds

Info

Publication number: WO2014113124A1
Application number: PCT/US2013/068381
Authority: WO
Inventors: Aswini DASH; Dimitris Katsoulis
Original assignee: Dow Corning Corporation
Priority date: 2013-01-21
Filing date: 2013-11-05
Publication date: 2014-07-24

Abstract

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.

Description

Process for Selective Production of Halosilanes From Silicon-Containing Ternary

Intermetallic Compounds

[0001] Methods of preparing halosilanes are known in the art. Typically, halosilanes are produced commercially by the Mueller-Rochow Direct Process, which comprises passing a halide compound over zero-valent silicon (Si⁰) in the presence of a copper catalyst and various optional promoters. Mixtures of halosilanes are produced by the Direct Process. When an organohalide is used, a mixture of organohalosilanes is produced by the Direct Process. When a hydrogen halide is used, a mixture of hydridohalosilanes is produced by the Direct Process.

[0002] The typical process for making the Si⁰ used in the Direct Process consists of the carbothermic reduction of S1O2 in an electric arc furnace. Extremely high temperatures are required to reduce the S1O2, so the process is energy intensive. Consequently, production of Si⁰ adds costs to the Direct Process for producing halosilanes. Therefore, there is a need for a more economical method of producing halosilanes that avoids or reduces the need of using Si⁰.

[0003] Various halosilanes find use in different industries. Hydridotrihalosilanes, such as trichlorosilane (HSiCl3), are useful as reactants in chemical vapor deposition processes for making high purity polycrystalline silicon, which is used in solar cells (solar grade polysilicon) or electronic chips (semiconductor grade polysilicon). Alternatively, hydridotrihalosilanes can be hydrolyzed in known processes to produce polysiloxanes, such as resins. Tetrahalosilanes can be used as precursors to make hydridohalosilanes and organohalosilanes. Diorganodihalosilanes, such as dimethyldichlorosilane, are hydrolyzed to produce a wide range of polyorganosiloxanes, such as

polydiorganosiloxanes. Organohydridohalosilanes can be used to make

polyorganohydridosiloxanes, which are useful as waterproofing agents; alternatively organohydridohalosilanes can be used as raw materials for making other

organohalosilanes. Therefore, there is a need for a method of selectively producing desired halosilanes.

BRIEF SUMMARY OF THE INVENTION

[0004] A process for preparing a reaction product comprising a halosilane comprises: contacting an organohalide with a ternary intermetallic compound comprising Si and two other metals at a temperature of 300 °C to 700 °C to form the reaction product.

DETAILED DESCRIPTION OF THE INVENTION

[0005] The Brief Summary of the Invention and the Abstract are hereby incorporated by reference. All ratios, percentages, and other amounts are by weight, unless otherwise indicated. The articles "a", "an", and "the" each refer to one or more, unless otherwise indicated by the context of the specification. The prefix "poly" means more than one. Abbreviations used herein are defined in Table 1 , below.

Table 1 - Abbreviations

[0006] "AlkyI" means an acyclic, branched or unbranched, saturated monovalent hydrocarbon group. Examples of alkyl groups include Me, Et, Pr, 1 -methylethyl, Bu, 1 - methylpropyl, 2-methylpropyl, 1 ,1 -dimethylethyl, 1 -methylbutyl, 1 -ethylpropyl, pentyl, 2- methylbutyl, 3-methylbutyl, 1 ,2-dimethylpropyl, 2,2-dimethylpropyl, hexyl, heptyl, 2- ethylhexyl, octyl, nonyl, and decyl. Alkyl groups have at least one carbon atom.

Alternatively, alkyl groups may have 1 to 12 carbon atoms, alternatively 1 to 10 carbon atoms, alternatively 1 to 6 carbon atoms, alternatively 1 to 4 carbon atoms, alternatively 1 to 2 carbon atoms, and alternatively 1 carbon atom.

[0007] "Aralkyi" and "alkaryl" each refer to an alkyl group having a pendant and/or terminal aryl group or an aryl group having a pendant alkyl group. Exemplary aralkyi groups include benzyl, tolyl, xylyl, phenylethyl, phenyl propyl, and phenyl butyl. Aralkyi groups have at least 4 carbon atoms. Monocyclic aralkyi groups may have 4 to 12 carbon atoms, alternatively 4 to 9 carbon atoms, and alternatively 4 to 7 carbon atoms. Polycyclic aralkyi groups may have 7 to 17 carbon atoms, alternatively 7 to 14 carbon atoms, and alternatively 9 to 10 carbon atoms.

[0008] "Alkenyl" means an acyclic, branched, or unbranched unsaturated monovalent hydrocarbon group, where the monovalent hydrocarbon group has a double bond. Alkenyl groups include Vi, allyl, propenyl, and hexenyl. Alkenyl groups have at least 2 carbon atoms. Alternatively, alkenyl groups may have 2 to 12 carbon atoms, alternatively 2 to 10 carbon atoms, alternatively 2 to 6 carbon atoms, alternatively 2 to 4 carbon atoms, and alternatively 2 carbon atoms.

[0009] "Alkynyl" means an acyclic, branched, or unbranched unsaturated monovalent hydrocarbon group, where the monovalent hydrocarbon group has a triple bond. Alkynyl groups include ethynyl and propynyl. Alkynyl groups have at least 2 carbon atoms.

Alternatively, alkynyl groups may have 2 to 12 carbon atoms, alternatively 2 to 10 carbon atoms, alternatively 2 to 6 carbon atoms, alternatively 2 to 4 carbon atoms, and alternatively 2 carbon atoms.

[0010] "Aryl" means a cyclic, fully unsaturated, hydrocarbon group. Aryl is exemplified by, but not limited to, Ph and naphthyl. Aryl groups have at least 5 carbon atoms.

Monocyclic aryl groups may have 6 to 9 carbon atoms, alternatively 6 to 7 carbon atoms, and alternatively 6 carbon atoms. Polycyclic aryl groups may have 10 to 17 carbon atoms, alternatively 10 to 14 carbon atoms, and alternatively 12 to 14 carbon atoms.

[0011] "Carbocycle" and "carbocyclic" refer to a hydrocarbon ring. Carbocycles may be monocyclic or alternatively may be fused, bridged, or spiro polycyclic rings. Carbocycles have at least 3 carbon atoms. Monocyclic carbocycles may have 3 to 9 carbon atoms, alternatively 4 to 7 carbon atoms, and alternatively 5 to 6 carbon atoms. Polycyclic carbocycles may have 7 to 17 carbon atoms, alternatively 7 to 14 carbon atoms, and alternatively 9 to 10 carbon atoms. Carbocycles may be saturated or partially unsaturated. [0012] "Cycloalkyl" refers to a saturated hydrocarbon group including a saturated carbocycle. Cycloalkyl groups are exemplified by cyclobutyl, cyclopentyl, cyclohexyl, and methylcyclohexyl. Cycloalkyl groups have at least 3 carbon atoms. Monocyclic cycloalkyl groups may have 3 to 9 carbon atoms, alternatively 4 to 7 carbon atoms, and alternatively 5 to 6 carbon atoms. Polycyclic cycloalkyl groups may have 7 to 17 carbon atoms, alternatively 7 to 14 carbon atoms, and alternatively 9 to 10 carbon atoms.

[0013] "Metallic" means that the metal has an oxidation number of zero.

[0014] "Purging" means to introduce a gas stream to the reactor containing the ternary intermetallic compound to remove unwanted gaseous or liquid materials.

[0015] "Residence time" means the time which a material takes to pass through a reactor system in a continuous process, or the time a material spends in the reactor in a batch process. For example, residence time may refer to the time during which one reactor volume of the intermetallic compound makes contact with the organohalide as the intermetallic compound passes through the reactor system in a continuous process or during which the intermetallic compound is placed within the reactor in a batch process. Alternatively, residence time may refer to the time for one reactor volume of reactant gases to pass through a reactor charged with the intermetallic compound, e.g., the time for one reactor volume of the organohalide to pass through a reactor charged with the intermetallic compound.

[0016] "Treating" means to introduce a gas stream to the reactor containing the ternary intermetallic compound to pre-treat the ternary intermetallic compound before contacting it with the organohalide.

[0017] The process for preparing the reaction product comprising the halosilane comprises: contacting the organohalide with the ternary intermetallic compound comprising Si and two other metals at a temperature of 300 °C to 700 °C to form the reaction product.

[0018] The organohalide may have the formula RX, where R is a monovalent organic group and X is a halogen. R may be selected from the group consisting of alkyl, aralkyl, alkenyl, alkynyl, aryl, and carbocyclic, as defined above. Alternatively, R may be an alkyl group or a cycloalkyl group. The alkyl groups for R may have 1 to 10 carbon atoms, alternatively 1 to 6 carbon atoms, and alternatively 1 to 4 carbon atoms. The cycloalkyl groups for R may have 4 to 10 carbon atoms, alternatively 6 to 8 carbon atoms. Alkyl groups containing at least three carbon atoms may have a branched or unbranched structure. Alternatively, R may be Me, Et, or Ph. Alternatively, R may be Me.

Alternatively, X may be Br, CI or I; alternatively Br or CI; and alternatively CI. Examples of the organohalide include, but are not limited to, methyl chloride, methyl bromide, methyl iodide, ethyl chloride, ethyl bromide, ethyl iodide, cyclobutyl chloride, cyclobutyl bromide, cyclohexyl chloride, and cyclohexyl bromide.

[0019] Alternatively, the organohalide may be an aliphatic hydrocarbyl halide. The aliphatic hydrocarbyl halide may be a compound of formula H_xC_yX_z, where subscript x represents average number of hydrogen atoms present, subscript y represents average number of carbon atoms present, and subscript z represents average number of halogen atoms present. Subscript x is 0 or more, subscript y is 1 or more, and subscript z is 1 or more. When the organohalide is a noncyclic aliphatic hydrocarbyl halide, then a quantity (x + z) = a quantity (2y + 2). When the organohalide is a monocyclic cycloalkyl halide, then the quantity (x + z) = 2y. Each X is independently a halogen atom, as described above. Alternatively, subscript y may be 1 to 10, alternatively 1 to 6, alternatively 1 to 4, and alternatively 1 . Alternatively, subscript z may be 1 to 4. Alternatively, subscript z may be at least 2, alternatively 2 to 4. Examples of suitable organohalides include, but are not limited to, methyl chloride (H3CCI), methylene chloride (H2CCI2), chloroform (HCCI3), carbon tetrachloride (CCI4), and dichloroethane.

[0020] The ternary intermetallic compound comprises Si and two other metals. A first other metal (M¹ ) is selected from Cu and Mg. Alternatively, M¹ is Cu. A second other metal (M²) is selected from Au, Ni, and Pd. Exemplary ternary intermetallic compounds include ternary intermetallic compounds of Cu, Si, and Pd; of Cu, Si, and Ni; of Cu, Si, and Au; and of Mg, Si, and Pd. Exemplary ternary intermetallic compounds include

Pd4Si4Cu2, Pd2Si2Cu6, Ni4Si4Cu2, Ni2Si2Cu6, AU4S14CU2, and Mg2SiPd. Ternary intermetallic compounds are commercially available. Alternatively, the ternary intermetallic compounds may be prepared by conventional methods, such as from the melt of the individual elements at predetermined stoichiometry using a heating apparatus such as electric arc melter. Alternatively, the ternary intermetallic compounds may be prepared by a process comprising vacuum impregnating two metal halides on silicon particles thereby producing a mixture, and mechanochemically processing the mixture under an inert atmosphere, thereby producing a reaction product comprising the ternary intermetallic compound. Ternary intermetallic compounds, such as intermetallic compounds of Cu, Si, and Pd may be prepared in this manner.

[0021 ] The process can be performed in any reactor suitable for the combining of gases and solids or any reactor suitable for the combining of liquids and solids. For example, the reactor configuration can be a batch vessel, packed bed, stirred bed, vibrating bed, moving bed, re-circulating beds, or a fluidized bed. Alternatively, the reactor for may be a packed bed, a stirred bed, or a fluidized bed. To facilitate reaction, the reactor should have means to control the temperature of the reaction zone.

[0022] The temperature at which the intermetallic compound and the organohalide are contacted is at least 300 °C, alternatively 300 °C to 700 °C; alternatively 300 °C to 600 °C; alternatively 300 °C to 500 °C; alternatively 500 °C to 700 °C; alternatively 600 °C to 700 °C; alternatively 500 °C to 600 °C; alternatively 300 °C to 320 °C; alternatively 350 °C to 400 °C; alternatively 370 °C to 400 °C; and alternatively 300 °C to 400 °C. Without wishing to be bound by theory, it is thought that if temperature is less than 300 °C, then the reaction may not proceed at a sufficient speed to produce the desired product; and if the temperature is greater than 700 °C, then the organohalide reactant and/or

organohalosilanes in the reaction product may decompose.

[0023] The pressure at which the organohalide (and, when present, the H2) are contacted with the intermetallic compound can be sub-atmospheric, atmospheric, or super- atmospheric. For example, the pressure may range from 0 kilopascals gauge (kPag) to 2000 kPag; alternatively 100 kPag to 1000 kPag; and alternatively 100 kPag to 800 kPag.

[0024] The mole ratio of H2 to organohalide contacted with the intermetallic compound may range from 10,000:1 to 0.01 :1 , alternatively 100:1 to 1 :1 , alternatively 20:1 to 5:1 , alternatively 20:1 to 4:1 , alternatively 20:1 to 2:1 , alternatively 20:1 to 1 :1 , and alternatively 4:1 to 1 :1 .

[0025] The residence time for the organohalide (and, when present H2) is sufficient for the organohalide (and, when present H2) to contact the intermetallic compound and form the reaction product. For example, a sufficient residence time may be at least 0.01 s, alternatively at least 0.1 s, alternatively 0.1 s to 10 min, alternatively 0.1 s to 1 min, and alternatively 0.5 s to 10 s. The desired residence time may be achieved by adjusting the flow rate of the organohalide (and when present the H2), or by adjusting the total reactor volume, or by any combination thereof.

[0026] When H2 is used, the organohalide and H2 may be fed to the reactor

simultaneously; however, other methods of combining, such as by separate pulses or separate streams, are also envisioned.

[0027] The intermetallic compound is present in a sufficient amount. A sufficient amount of intermetallic compound is enough intermetallic compound to form the halosilane, described below, when the organohalide (and, when present H2) is contacted with the intermetallic compound. For example, a sufficient amount of intermetallic compound may be at least 0.01 mg intermetallic compound/cm³ of reactor volume; alternatively at least 0.5 mg intermetallic compound/cm³ of reactor volume, and alternatively 1 mg to 10,000 mg intermetallic compound/cm³ of reactor volume.

[0028] There is no upper limit on the time for which the process is conducted. For example, the process may be conducted for at least 0.1 s, alternatively 1 s to 30 hr, alternatively 1 min to 8 hr, alternatively 1 hr to 5 hr, and alternatively 3 hr to 30 hr.

[0029] If the organohalide is a liquid at or below standard temperature and pressure (or the temperature and pressure selected for the process), the process may further comprise vaporizing the organohalide by known methods, such as pre-heating, before contacting the organohalide with the intermetallic compound. Alternatively, the process may further comprise bubbling the hydrogen through liquid organohalide to vaporize the organohalide before contacting with the intermetallic compound.

[0030] If the organohalide is a solid at or below standard temperature and pressure, the process may further comprise pre-heating above the melting point and liquefying or vaporizing the organohalide before contacting with the intermetallic compound.

[0031] The process described herein may further comprise purging and/or treating before contacting the organohalide with the intermetallic compound. "Purging" and "Treating" are as defined above. This step comprises introducing an inert gas stream into the reactor containing intermetallic compound. Purging and/or treating may be performed at ambient or elevated temperature, e.g., at least 25 °C, alternatively at least 300 °C, alternatively 25 °C to 500 °C, alternatively 300 °C to 500 °C. Purging may be performed to remove unwanted materials, such as H2, O2, H2O and/or HX, where X is as defined above.

Purging and/or treating may be accomplished with an inert gas, such as N2 or Ar, or with a reactive gas, such as H2 or the organohalide.

[0032] Alternatively, the process may optionally further comprise: contacting the ternary intermetallic compound with H2 before and/or during contacting with the organohalide. H2 can be added to the organohalide stream. Alternatively, H2 and organohalide can be added concurrently to the reactor in separate streams.

[0033] The process may further comprise recovering the halosilane from the reaction product. The halosilane may be recovered from the reaction product by, for example, removing gaseous product from the reactor followed by isolation by distillation. The reaction product produced by the method described and exemplified herein may comprise a halosilane of formula Rm^HnSiX(4-m-n)_> where R and X are as defined and exemplified above; subscript m is 1 , 2, or 3, alternatively m is 1 or 2; subscript n is 0, 1 , or 2, alternatively n is 0 or 1 ; alternatively n is 0; and a quantity (m + n) is 1 , 2, or 3. [0034] The process described herein selectively produces halosilanes. Using the description herein, process conditions (e.g., the selection of ternary intermetallic compound, relative amounts of each metal in the ternary intermetallic compound, process temperature, and the organohalide selected, and whether H2 is added during contacting the ternary intermetallic compound and the organohalide) may be selected to produce a desired halosilane. For example, when M¹ is Mg and M² is Pd, and the temperature is 300 °C to 400 °C, the halosilane may have formula P>aSi (4-a). where R and X are as described above, and subscript a is 1 , 2, or 3.

[0035] Alternatively, in another embodiment M¹ is Cu and M² is Pd, and the process temperature is 300 °C to 400 °C. In this embodiment, the temperature may be 350 °C to 400 °C, and the halosilane has formula Rb^HcSiX(4-b-c)_> where R and X are as described above, subscript b is 1 or 2, and subscript c is 0 or 1 , and a quantity (b + c) = 1 or 2.

Alternatively, in the embodiment where M¹ is Cu and M² is Pd, when the temperature is 300 °C to 320 °C, the halosilane has formula RdSiX(4-d). where R and X are as described above, and subscript d is 1 or 2.

[0036] Alternatively, in another embodiment M¹ is Cu and M² is Au. In this embodiment, where the temperature is 400 °C to 500 °C, the halosilane has formula R_eHfSiX(4_-e-f), where R and X are as described above, subscript e is 1 , 2, or 3, subscript f is 0 or 1 , and a quantity (e + f) is 1 , 2, or 3. Alternatively, in the embodiment where M¹ is Cu and M² is Au, and the temperature 600 °C to 700 °C, the halosilane has formula RHgSiX^.g), where R and X are as described above, and subscript g is 0 or 1 .

[0037] Alternatively, in another embodiment M¹ is Cu and M² is Ni. In this embodiment, where the temperature is 300 °C to 600 °C, the halosilane has formula Rh^HjSiX(4-h-j), where R and X are as described above, subscript h is 1 or 2, and subscript i is 0 or 1 , and a quantity (h + i) = 1 , 2, or 3. Alternatively, in the embodiment where M¹ is Cu and M² is Ni and the temperature is 600 °C to 700 °C, the halosilane has formula HjSiX^.j), where each X is independently a halogen and subscript j is 0 or 1 .

[0038] The process described herein may be used to produce diorganodihalosilanes. Examples of diorganodihalosilanes prepared according to the present process include, but are not limited to, dimethyldichlorosilane (i.e., (CH3)2SiCl2), dimethyldibromosilane, diethyldichlorosilane, and diethyldibromosilane. Examples of other organohalosilanes that may be produced include, but are not limited to, organotrihalosilanes such as

methyltrichlorosilane (i.e.,

Alternatively, the process described herein may be used to produce hydridohalosilanes such as trichlorosilane (i.e., HS1CI3). Alternatively, the process described herein may be used to produce silicon tetrahalides, such as silicon tetrachloride (i.e., S1CI4) . Alternatively, the process described herein may be used to produce organohydridohalosilanes, such as and methyldichlorosilane (i.e., CH3(H)SiCl2) and dimethylchlorosilane (i.e., (CH3)2HSiCI).

EXAMPLES

[0039] These examples are intended to illustrate some embodiments of the invention and should not be interpreted as limiting the scope of the invention set forth in the claims. In these examples, the reaction apparatus used was an open-ended glass tube with quartz wool to hold the ternary silicide in place. The tube was connected to a flow reactor comprising a Lindberg/Blue Minimite 1 inch tube furnace and Brooks mass flow controller to control gas flow. An O-ring was fitted over the glass tube at the inlet to prevent flow of gases around the outside. The reactor effluent was passed through an actuated 6-way valve (Vici) with constant 100 uL injection loop before being discarded. Samples were taken from the reactor effluent by actuating the injection valve and the 100 uL sample passed directly into the injection port of a 6890A Agilent GC and GC-MS equipped with a TCD and a FID for analysis. The hydrogen was ultra high purity hydrogen from Airgas (Radnor, PA). Ternary intermetallic compounds were obtained from ACI alloys.

[0040] In example 1 , 0.6 g of Pd4Si4Cu2 was loaded into the glass tube reactor and treated with 10 seem of an inert gas (either Nitrogen or Argon) at 300 °C for 2 hr. Next, the flow of inert gas was stopped and MeCI was flowed through the reactor. Samples were taken from the reactor effluent and injected into a GC/GC-MS for analysis using an online switching valve. The reaction was run while varying the reaction temperature as well as repetition experiments carried out under the same reaction conditions. The reaction conditions, organohalosilanes produced, and yields are listed in Table 2.

Table 2. Production of Chlorosilanes from Reaction of Pd4Si4Cu₂ with Methyl Chloride

[0041] In example 2, 0.6 g of Pd2Si2Cue was loaded into the quartz glass tube reactor.

The Pd2Si2Cu6 was treated with 10 seem nitrogen at 300 °C for 2 hours. Next, the flow of inert gas was stopped, and MeCI (30 seem) was flowed through the reactor. Samples were taken from the reactor effluent and injected into a GC/GC-MS for analysis. The analysis showed selective formation of MeSiC^ as the organohalosilane product. The reaction was run continuously at 300 °C for 2 hr, and at 400 °C for 1 hr. The liquid condensed was collected and analyzed by GC. Analysis of the reactor effluent showed production of MeSiCI3 (91 %) with the balance being SiCI4 (1 %) and (MeO)SiCI3 (8%).

[0042] In example 3, 0.52 g of Ni4Si4Cu2 was loaded into a quartz glass tube reactor and treated with 10 seem Ar at 300 °C for 2 hr. Next, the flow of inert gas was stopped and MeCI was flowed through the reactor. Samples were taken from the reactor effluent and injected into a GC/GC-MS for analysis using an online switching valve. The reaction was run while varying the reaction temperature and flow rate of MeCI. H2 was also added at different flow rates for some runs. The reaction conditions, organohalosilanes produced, and yields are listed in Table 3.

Table 3. Production of Chlorosilanes from Reaction of Ni4Si4Cu₂ with Methyl Chloride

[0043] In example 4, 0.56 g of Ni2Si2Cu6 was loaded into a quartz glass tube reactor and treated with 10 seem Ar at 300 °C for 2 hr. Next, the flow of inert gas was stopped and MeCI was flowed through the reactor. Samples were taken from the reactor effluent and injected into a GC/GC-MS for analysis using an online switching valve. The process was run while varying the reaction temperature and flow rate of MeCI. H2 was also added at different flow rates for some runs. The reaction conditions, organohalosilanes produced, and yields are listed in Table 4.

Table 4. Production of Chlorosilanes from Reaction of Ni2Si2Cue with Methyl Chloride

[0044] In example 5, 0.55 g of AU4S14CU2 was loaded into a quartz glass tube reactor and treated with 10 seem Ar at 300 °C for 2 hr. Next, the flow of inert gas was stopped and MeCI was flowed through the reactor. Samples were taken from the reactor effluent and injected into a GC/GC-MS for analysis using an online switching valve. The process was run while varying the reaction temperature and flow rate of MeCI. The reaction conditions, organohalosilanes produced, and yields are listed in Table 5.

Table 5. Production of Chlorosilanes from Reaction of AU4S14CU2 with Methyl Chloride

[0045] In example 6, 0.55 g of IVk^SiPd was loaded into a quartz glass tube reactor and treated with 10 seem Ar at 300 °C for 2 hr. Next, the flow of inert gas was stopped and MeCI (3.6 seem) was flowed through the reactor at 350 °C. Samples were taken from the reactor effluent and injected into a GC/GC-MS for analysis using an online switching valve. This analysis showed production of the following organohalosilanes: Me3SiCI (43.6%),

MeSiCl3 (1 .4%), Me2SiCl2 (3.4%) and the balance was mixture of lower and higher carbosilanes. The reaction was run at 400 °C, and this showed production of the following organohalosilanes: Μβββ (30.7%), MeSiCl3 (5.6%), Me2SiCl2 (8.6%) and the balance was mixture of lower and higher carbosilanes.

[0046] With respect to any Markush groups relied upon herein for describing particular features or aspects of various embodiments, it is to be appreciated that different, special, and/or unexpected results may be obtained from each member of the respective Markush group independent from all other Markush members. Each member of a Markush group may be relied upon individually and or in combination and provides adequate support for specific embodiments within the scope of the appended claims.

[0047] It is also to be understood that any ranges and subranges relied upon in describing various embodiments of the present disclosure independently and collectively fall within the scope of the appended claims, and are understood to describe and contemplate all ranges including whole and/or fractional values therein, even if such values are not expressly written herein. The enumerated ranges and subranges sufficiently describe and enable various embodiments of the present disclosure, and such ranges and subranges may be further delineated into relevant halves, thirds, quarters, fifths, and so on. As just one example, a range of "300 to 700" may be further delineated into a lower third, i.e., 300 to 433, a middle third, i.e., 434 to 566, and an upper third, i.e., 567 to 700, which individually and collectively are within the scope of the appended claims, and may be relied upon individually and/or collectively and provide adequate support for specific

embodiments within the scope of the appended claims. In addition, with respect to the language which defines or modifies a range, such as "at least," "greater than," "less than," "no more than," and the like, it is to be understood that such language includes subranges and/or an upper or lower limit. As another example, a range of "at least 0.1 %" inherently includes a subrange from 0.1 % to 35%, a subrange from 10% to 25%, a subrange from 23% to 30%, and so on, and each subrange may be relied upon individually and/or collectively and provides adequate support for specific embodiments within the scope of the appended claims. Finally, an individual number within a disclosed range may be relied upon and provides adequate support for specific embodiments within the scope of the appended claims. For example, a range of Ί to 9" includes various individual integers, such as 3, as well as individual numbers including a decimal point (or fraction), such as 4.1 , which may be relied upon and provide adequate support for specific embodiments within the scope of the appended claims.

[0048] The subject matter of all combinations of independent and dependent claims, both singly and multiply dependent, is expressly contemplated but is not described in detail for the sake of brevity. The disclosure has been described in an illustrative manner, and it is to be understood that the terminology which has been used is intended to be in the nature of words of description rather than of limitation. Many modifications and variations of the present disclosure are possible in light of the above teachings, and the disclosure may be practiced otherwise than as specifically described.

Claims

1 . A process for preparing a reaction product comprising a halosilane, where the process comprises contacting an organohalide with a ternary intermetallic compound comprising Si and two other metals at a temperature from 300 °C to 700 °C to form the reaction product and the halosilane has formula Rm^HnSiX(4-m-n)_> where each R is independently a monovalent organic group; each X is independently a halogen; subscript m is 1 , 2, or 3; subscript n is 0, 1 , or 2; and a quantity (m + n) is 1 , 2, or 3.

2. The process of claim 1 , further comprising one or more steps, where the one or more steps are selected from:

purging and/or treating a reactor containing the ternary intermetallic compound before contacting the organohalide with the ternary intermetallic compound; and/or

vaporizing the organohalide before contacting the organohalide with the ternary intermetallic compound; and/or

liquefying the organohalide before contacting the organohalide with the ternary intermetallic compound; and/or

contacting the ternary intermetallic compound with H2 before and/or during contacting with the organohalide; and/or

recovering the halosilane from the reaction product.

3. The process of claim 1 or claim 2, where the two other metals are Mg and Pd.

4. The process of claim 3, where the temperature is 300 °C to 400 °C, and the halosilane has formula R_aSiX(4_-a), where each R is independently hydrocarbyl, each X is independently a halogen, and subscript a is 1 , 2, or 3.

5. The process of claim 1 or claim 2, where the two other metals are Cu and Pd, and the temperature is 300 °C to 400 °C.

6. The process of claim 5, where the temperature is 350 °C to 400 °C, and the halosilane has formula Rb^HcSiX(4-b-c)_> where each R is independently hydrocarbyl, each X is independently a halogen, subscript b is 1 or 2, and subscript c is 0 or 1 , and a quantity (b + c) = 1 or 2.

7. The process of claim 5, where the temperature is 300 °C to 320 °C, and the halosilane has formula RdSiX(4-d). where each R is independently hydrocarbyl, each X is

independently a halogen, and subscript d is 1 or 2.

8. The process of claim 1 or claim 2, where the two other metals are Au and Cu.

9. The process of claim 8, where the temperature is 400 °C to 500 °C and the halosilane has formula R_eHfSiX(4_-e-f), where each R is independently hydrocarbyl, each X is independently a halogen, subscript e is 1 , 2, or 3, subscript f is 0 or 1 , and a quantity (e + f) is 1 , 2, or 3.

10. The process of claim 8, where the temperature is 600 °C to 700 °C and the halosilane has formula RHgSiX^.g), where each R is independently hydrocarbyl, each X is independently a halogen, and subscript g is 0 or 1 .

1 1 . The process of claim 1 or claim 2, where the two other metals are Cu and Ni.

12. The process of claim 1 1 , where the temperature is 300 °C to 600 °C, and the halosilane has formula R ^HiSiX(4- -i)_> where each R is independently hydrocarbyl, each X is independently a halogen, subscript h is 1 or 2, and subscript i is 0 or 1 , and a quantity (h + i) = 1 , 2, or 3.

13. The process of claim 1 1 , where the temperature is 600 °C to 700 °C, and the halosilane has formula HjSiX^.j), where each X is independently a halogen and subscript j is 0 or 1 .

14. The process of any one of claims 3 to 12, where R is alkyl and X is selected from CI and Br.

15. The process of any one of the preceding claims, further comprising using the halosilane as a reactant in a process to make a product selected from polycrystalline silicon, a polysiloxane, a hydridohalosilane, a polyorganosiloxane, and a

polyorganohydridohalosiloxane.