409results about "Halogenated silanes" patented technology

The invention discloses a preparation method of high-purity diiodosilane, which comprises the following steps: firstly, preparing a p-phenylsilane solution from phenyl trichlorosilane and sodium hydride as raw materials, rectifying and purifying the p-phenylsilane solution, directly reacting the p-phenylsilane solution with iodine to generate diiodosilane, and reacting phenylsilane with iodine to directly generate diiodosilane; in the process of preparing diiodosilane from phenylsilane, conditions are mild, the reaction process is controllable, the reaction time is shortened by controlling the temperature in the synthesis process and increasing the pressure of a reaction system, hydrogen iodide overflow is reduced, sodium hydride is adopted as a reducing agent in the reaction process, and the yield of diiodosilane is increased. The solid waste can be recycled, the cost can be effectively reduced, and industrialization of diiodosilane is facilitated.

The present invention refers to a SiC and Chlorosilane production system 2540, comprising at least one CVD SiC production reactor 850, in particular SiC fluidized bed reactor 850a, in particular according to claim 9, and a Chlorosilane production unit 2550, wherein the Chlorosilane production unit 2550 comprises at least a bed reactor 2416, in particular a fixed bed reactor or a fluidized bed reactor, for generating Chlorosilanes by reacting at least one fraction of the vent gas mixture provided via the vent gas outlet 216 of the CVD SiC production reactor 850 and Si, wherein further fractions of the vent gas mixture at least comprise H2 and a C-bearing molecule, in particular methane, and wherein Si is provided as solid 2398 inside the bed reactor 2416.

The invention relates to a phosphorite wet processing method, and belongs to the technical field of chemical engineering. The phosphorite wet processing method comprises the following steps: A, phosphorite acid leaching: carrying out acidolysis leaching on a phosphorite raw material, and carrying out solid-liquid separation to obtain wet-process phosphoric acid; b, removing metal ions from wet-process phosphoric acid; and C, wet-process phosphoric acid defluorination: extracting fluosilicic acid in wet-process phosphoric acid at 10-70 DEG C by adopting a wet-process phosphoric acid defluorination extraction agent, and carrying out phase splitting to obtain defluorinated purified phosphoric acid and an organic phase loaded with fluosilicate. According to the invention, high-value utilization of low-grade phosphorite resources is realized. According to the method, impurities can be fully removed, the loss rate of phosphoric acid is low, the purity of the finally obtained phosphate product reaches 97% or above, the product quality is high, and the requirements of different fields for high-quality phosphate can be met. The method is simple in process, low in energy consumption and low in cost.

The invention relates to the technical field of polycrystalline silicon system catalysts, in particular to a preparation method of a polycrystalline silicon catalyst for new energy, which comprises the following steps: preparing mesoporous polystyrene microspheres; the preparation method comprises the following steps: dispersing mesoporous polystyrene microspheres in a metal salt solution for precipitation reaction, dispersing the obtained supported polystyrene microspheres in ethanol, then adding stronger ammonia water and tetraethyl orthosilicate for stirring reaction to obtain supported silicon dioxide microspheres; and calcining in a carbon monoxide atmosphere to prepare the polycrystalline silicon system catalyst. According to the preparation method, loading and precipitation of metal salt are carried out by dissolving a large number of mesopores in polystyrene microspheres, then the polystyrene microspheres loaded with metal precipitation particles are fixed by a sol-gel method, and the interior and the surface of the generated silicon dioxide microspheres are mingled with the loaded polystyrene microspheres; and high-temperature reduction calcination is carried out in the atmosphere of carbon monoxide, so that the prepared polycrystalline silicon system catalyst has relatively high tetrachlorosilane conversion rate and long-time use stability.

The invention discloses a catalyst for preparing trichlorosilane and a catalytic preparation method of trichlorosilane. The catalyst is prepared from the following components in percentage by mass: weighed copper nitrate, zinc nitrate, aluminum nitrate, lanthanum nitrate and the balance of a carrier, the preparation method comprises the following specific steps: S1, filling a catalyst; S2, purifying raw material gas; S3, reacting; and S4, separating and purifying a product, namely discharging a reacted gas product from an outlet of a reactor, and condensing through a condenser. In the prepared catalyst, the activity and selectivity of the catalyst are remarkably improved through the synergistic effect of the copper-zinc-aluminum composite oxide and the rare earth element lanthanum, the electronic structure and the surface acid-base property of the catalyst can be adjusted through doping of lanthanum, the reaction of silicon powder and hydrogen chloride is promoted, meanwhile, side reactions are inhibited, and the service life of the catalyst is prolonged. And the yield of trichlorosilane is improved.

The present invention discloses a method for separating nickel and iron from a nickel-iron alloy by chlorination roasting: (1) placing the nickel-iron alloy in a roasting furnace; (2) introducing a gaseous chlorinating agent into the roasting furnace for staged roasting to obtain roasting slag and a roasting gas phase; wherein the gaseous chlorinating agent is a mixture of chlorine and gaseous ferric chloride; and (3) condensing the roasting gas phase obtained in step (2) in stages to obtain solid ferric chloride and liquid silicon tetrachloride, respectively. The present invention controls the composition of the chlorinating agent during the chlorination roasting process to achieve selective and directional volatilization of iron into the gas phase while preventing nickel from being chlorinated. Thus, nickel and iron in the nickel-iron alloy can be separated in a single step, and the process flow is short.

The invention belongs to the technical field of trichlorosilane purification, and discloses an adsorbent for adsorbing phosphorus impurities in trichlorosilane and a preparation method and application thereof.The preparation method comprises the steps that activated carbon is immersed in a solution containing ammonium metavanadate and oxalic acid, ultrasonic treatment and drying are conducted, and a vanadium oxide / carbon material mixture is obtained; calcining the vanadium oxide / carbon material mixture, and performing reduction treatment to obtain the oxygen vacancy-rich activated carbon loaded vanadium oxide adsorbent. The activated carbon loaded vanadium oxide adsorbent rich in oxygen vacancies is prepared by using a dipping-calcining-reducing method, and phosphorus impurities are adsorbed and removed by using the interaction of the activated carbon loaded vanadium oxide adsorbent and PCl3. The active carbon loaded vanadium oxide adsorbent rich in oxygen vacancies interacts with PCl3, so that trace PCl3 can be efficiently removed.

A method for preparing diiodosilane, according to one aspect of the present invention, may comprise: a step of injecting an iodine source into a reaction vessel; a step of injecting an inert gas into the reaction vessel and purging same; a first synthesis step of adding a non-coordinating solvent and an ethylene diamine-based catalyst to the reaction vessel, and then stirring same to synthesize a reaction solution; a second synthesis step of maintaining the temperature inside the reaction vessel at a predetermined temperature, injecting dichlorosilane (DCS) into the reaction solution for a predetermined period of time, and then stirring same to increase the yield; a step of filtering out solids from the reaction solution and washing same; and a step of concentrating and reducing the pressure of the reaction filtrate obtained after the washing step, thereby recovering diiodosilane, and can prepare diiodosilane with high yield and / or high purity at low cost.

The invention provides an efficient trichlorosilane synthetic furnace and an intelligent temperature control method thereof. The efficient trichlorosilane synthetic furnace comprises a reactor body and an intelligent temperature control module, the reactor body comprises a shell; the shell comprises a conical area and a cylindrical area; the cylindrical area sequentially comprises a lower-section reaction area, a middle-section reaction area and an upper-section reaction area from bottom to top, and cooling devices are independently arranged on the outer sides of the reaction areas respectively; an internal part is arranged in the lower section reaction area; the intelligent temperature control module comprises a temperature sensor unit, an intelligent control unit and a flow adjusting unit. According to the invention, by arranging the internal part and the intelligent temperature control module, intelligent temperature control is realized, the temperature uniformity of each reaction area in the trichlorosilane synthetic furnace is effectively improved, and the conversion rate of trichlorosilane is greatly improved.

The invention relates to the technical field of semiconductor materials, in particular to a method for preparing a semiconductor material from high-purity quartz sand. The method comprises the following steps: firstly, grafting and modifying the surface of quartz sand through 3-aminopropyltriethoxysilane, complexing metal impurities by using amino functional groups, and improving the purity of a precursor from the source; secondly, hydrogen / deuterium gas pulse back-and-forth switching is adopted, surface hydrogen atom dynamics is regulated and controlled through the isotope effect, and an etching-nucleation synergistic window is created; and finally, through sequential alternate supply of silane and disilane, time separation of a weak bond etching period and a high-activity nucleation period is realized. The prepared semiconductor material shows excellent performance, and compared with a traditional method, the technical problem of low-temperature deposition of a high-quality semiconductor film is solved through full-process optimization from a material source to a deposition end.

The invention belongs to the field of inorganic chemical industry, and particularly relates to a method and a system for efficiently utilizing a phosphate fertilizer byproduct, the method comprises the following steps: carrying out acidolysis on fluosilicic acid with the concentration of more than or equal to 45% wt and concentrated sulfuric acid to generate a mixed solution of silicon tetrafluoride gas and fluorosulfonic acid; the mass ratio of the fluosilicic acid to the concentrated sulfuric acid is controlled to be 1: (4-15); pyrolyzing the obtained fluorosulfonic acid to generate dilute sulphuric acid, hydrogen fluoride and water vapor, forming 98% concentrated sulphuric acid from part of dilute sulphuric acid and fuming sulphuric acid, drying hydrogen fluoride to obtain crude hydrogen fluoride gas, and condensing and rectifying to obtain anhydrous hydrogen fluoride; the rest dilute sulphuric acid is partially compounded and then returned for acidolysis, and the rest dilute sulphuric acid is used for producing white carbon black and flows back to a wet-process phosphoric acid system; and circularly absorbing the obtained silicon tetrafluoride gas by using secondary concentrated fluosilicic acid to obtain fluosilicic acid with the mass concentration of more than or equal to 45%, recycling the fluosilicic acid for acidolysis reaction, and modifying the concentrated by-product silicon dioxide to obtain the high-activity white carbon black. The problems of energy consumption and cost are solved, and efficient circulation and poly-generation of fluorine and silicon resources are achieved in the whole process.

The utility model provides a system for synthesizing trichlorosilane. The system for synthesizing trichlorosilane comprises a trichlorosilane synthesis reaction device, a first gas-solid separation unit, a first tail gas treatment unit, a silicon tetrachloride hydrogenation reaction device, a second gas-solid separation unit, a second tail gas treatment unit and a product separation and purification unit. According to the system, through the technological process of fusing the trichlorosilane synthesis reaction and the silicon tetrachloride hydrogenation reaction, efficient utilization of silicon powder, hydrogen and silicon tetrachloride is achieved, the investment and operation cost is saved, and meanwhile the raw material consumption is reduced.

The present invention relates to the technical field of hydrogen fluoride preparation, and particularly to a method for separating a mixed solution containing hydrogen fluoride and sulfuric acid. The separation method includes: A) Concentrated fluorosilicic acid and concentrated sulfuric acid react in a reaction device to generate silicon tetrafluoride gas and a sulfuric acid solution containing hydrogen fluoride; B) The first part of the sulfuric acid solution containing hydrogen fluoride is subjected to two-stage separation to obtain hydrogen fluoride gas; the second part of the sulfuric acid solution containing hydrogen fluoride is heated and recycled to the reaction device. The present invention adopts two-stage separation; another path of the sulfuric acid solution containing hydrogen fluoride led out after the main reaction enters the reaction device again after being heated, with relatively low energy consumption. Therefore, the separation method provided by the present invention separates hydrogen fluoride from the sulfuric acid solution with relatively low energy consumption and can reduce fluorine loss.

The utility model relates to a trichlorosilane adsorption tower in the technical field of adsorption equipment, which comprises a tower body, an air inlet pipe and an emptying pipe are arranged at the bottom of the tower body, and an exhaust pipe is arranged at the top of the tower body; the interior of the tower body is divided into a spraying area and an adsorption area from bottom to top, a spraying pipe is arranged at the top of the spraying area, a spherical gas distribution plate is arranged at the bottom of the spraying area, gas distribution holes are fully distributed in the gas distribution plate, and the gas inlet pipe is located below the gas distribution plate; the adsorption area comprises a filler layer, the filler layer is an activated carbon layer, a heat exchange assembly is arranged in the filler layer, the heat exchange assembly comprises a coiled pipe, and the coiled pipe is connected with a medium inlet pipe and a medium outlet pipe. According to the utility model, trichlorosilane can be subjected to impurity removal and purification after spraying and adsorption in sequence, the efficiency is high, and the effect is good; the temperature of the filler area can be flexibly adjusted according to needs, the adsorption effect can be improved, the filler can be purified, and the next adsorption effect is not affected.

The electronic-grade silane gas continuous production preparation system comprises a cold hydrogenation treatment device, an inlet of the cold hydrogenation treatment device is connected with a raw material supply system, and an outlet of the cold hydrogenation treatment device is connected with a cold hydrogenation rectifying tower through a pipeline. The cold hydrogenation rectifying tower is sequentially connected with the boron and phosphorus removal adsorption column, the first-stage disproportionator, the first tower, the second tower, the second-stage disproportionator, the third tower and the fourth tower through pipelines, and electronic-grade silane in the fourth tower is used for being conveyed to a silane tank area; the first tower is used for removing silicon tetrachloride produced after the disproportionation reaction of the first-stage disproportionator; the second tower is used for separating the extracted chlorosilane material; the third tower is used for separating silane from chlorosilane; and the fourth tower is used for discharging light impurities and heavy impurities and conveying gas-phase electronic-grade silane into a silane tank area. The device and the method realize continuous, efficient and high-purity production of the electronic-grade silane gas, and have the advantages of low energy consumption, low cost, thorough impurity removal and the like.

The present disclosure relates to a method or producing silicon tetrafluoride from fluorosilicic acid. In one implementation, a first stream comprising fluorosilicic acid and a second stream comprising sulfuric acid are reacted in a pressure regulator to produce an outgoing liquid stream comprising silicon tetrafluoride. The outgoing liquid is then fed into at least one separator which outputs at least one gas stream containing silicon tetrafluoride and at least one liquid stream. The at least one gas stream is fed into at least one additional separator which separates the at least one gas stream into at least one stream of purified silicon tetrafluoride gas. In some implementations, the at least one liquid stream is recycled back into the at least one separator.

The invention discloses a diiodosilane purification method and a purification processing system, relating to the technical field of diiodosilane. A driving component is provided on a mounting shell, an inner liner is clamped on an output end of the driving component, the driving component is slidably connected to a sliding groove provided on the mounting shell, the inner liner is located in a sliding cavity in the mounting shell, the sliding cavity is communicated with the sliding groove, a limiting component is installed on the mounting shell, a notch is provided on the mounting shell, the limiting component is tilted toward the notch, and the crystals can be quickly taken out by taking out the inner liner, thereby enhancing work efficiency, facilitating the rapid removal of the crystals, and enabling the next crystallization to be carried out quickly. Moreover, by arranging a filter screen and a railing on the inner liner, the residual liquid in the inner liner can be quickly discharged, thereby preventing the residual liquid from affecting the purity of the diiodosilane.

The invention discloses a diiodosilane purification method and a purification processing system, and relates to the technical field of diiodosilanes. A driving assembly is arranged on a mounting shell, an inner container piece is clamped to the output end of the driving assembly, the driving assembly is in sliding connection with a sliding groove formed in the mounting shell, the inner container piece is located in a sliding cavity in the mounting shell, and the inner container piece is connected with the driving assembly in a sliding mode; the sliding cavity is communicated with the sliding groove, a limiting assembly is mounted on the mounting shell, a notch is formed in the mounting shell, the limiting assembly inclines towards the notch, crystals can be rapidly taken out by taking out the inner container piece, the working efficiency is improved, the crystals can be rapidly taken out conveniently, the next time of crystallization can be rapidly carried out, and the crystallization efficiency is improved. And a filter screen and a handrail are arranged on the inner container piece, so that residual liquid in the inner container piece can quickly flow out, and the residual liquid is prevented from influencing the purity of diiodosilane.

The invention provides a silicon tetrafluoride purification method and a preparation method of modified activated carbon for deep purification of silicon tetrafluoride, and belongs to the technical field of silicon tetrafluoride purification. The silicon tetrafluoride purification method comprises the following steps that silicon tetrafluoride raw material gas is sequentially adsorbed with activated carbon and a molecular sieve, and primary purified silicon tetrafluoride is obtained; introducing ammonia gas into the primarily purified silicon tetrafluoride for reaction, carrying out gas-solid separation, and removing impurities from the obtained gas component by using modified activated carbon to obtain secondarily purified silicon tetrafluoride; a modification method of the modified activated carbon comprises the following steps: reacting activated carbon with fluorine-containing gas at 80-100 DEG C; and rectifying the secondarily purified silicon tetrafluoride to obtain the high-purity silicon tetrafluoride. The purity of the purified silicon tetrafluoride gas reaches 6N grade or above, the time for the modified activated carbon to reach adsorption saturation is long, the service cycle is long, and the production cost can be effectively reduced.

The invention provides a method and a system for recycling polycrystalline silicon slag slurry. The recycling method of the polycrystalline silicon slag slurry comprises the following steps: carrying out aluminum removal treatment and titanium removal treatment on a high-boiling-point substance generated by slag slurry treatment to obtain an intermediate high-boiling-point substance; carrying out cracking reaction on the intermediate high-boiling residue and hydrogen chloride to obtain a cracking product and residual liquid; carrying out rectification treatment on the cracking product to obtain gas-phase chlorosilane and a low-boiling-point substance; carrying out concentration treatment on the residual liquid to obtain gas-phase chlorosilane and a concentrated product; and carrying out first hydrolysis treatment on the concentrated product to obtain hydrogen and waste liquid. According to the method for recovering the polycrystalline silicon slag slurry, the high-boiling residues in the polycrystalline silicon slag slurry can be efficiently recovered, and the resource utilization rate is increased.

The application discloses a kind of feed dynamic regulation methods of synthesizing trichlorosilane, through multispectral synergistic detection, through the accurate calculation of key parameters such as hydroxyl inhibition factor, amorphous phase activity gain and metal impurity inhibition factor, the activity condition of silicon powder in fluidized bed can be accurately and real-time reflected, the technical bottleneck that silicon powder activity cannot be monitored on line is broken through, and then in industrial production, for the proportion of fluidized bed feed etc. Real-time regulation provides control basis.Through feed dynamic regulation mechanism, silicon powder feed rate, H2 / SiCl4 ratio and catalyst addition amount can be optimized in real time, ensure that silicon powder is always in high activity state, promote the reaction to proceed, improve trichlorosilane yield and purity, solve the problem that traditional fixed regulation mode and silicon powder dynamic activity do not match, and then improve regulation accuracy.

The invention relates to a method and a system for preparing trichlorosilane from ferrosilicon, the method comprises the following steps: taking ferrosilicon, silicon tetrachloride and hydrogen as raw materials, fully reacting in a fluidized bed reactor to obtain trichlorosilane and FeSiy alloy, xlt; 40). The system comprises a fluidized bed reactor (200), a cyclone separator (300), a washing tower (400), a gas-liquid separator (500) and a coarse distillation tower (600). Compared with the prior art, the method has the remarkable characteristics that the silazite is used as a silicon source and is low in cost and easy to obtain, the reaction activity of trichlorosilane and FeSiy generated by reaction of the silazite, silicon tetrachloride and hydrogen is high, the utilization rate of silicon elements in the compound is high, no extra catalyst needs to be added in the co-hydrogenation reaction, meanwhile, the byproduct FeSiy alloy is produced, and the production cost is low.

This invention provides a system and method for removing high and low boiling points in polysilicon production. The system includes a first distillation column comprising a top rectifying section, a bottom stripping section, and a separation section between the rectifying and stripping sections, all of which are sequentially interconnected. The separation section includes a pre-fractionation section and a main fractionation section arranged side-by-side but not interconnected. The main fractionation section includes, from top to bottom, a first main fractionation section and a second main fractionation section that are interconnected. The pre-fractionation section has a low-boiling material inlet, the stripping section has a bottom outlet, and the first main fractionation section has a first outlet. The outlet of the disproportionation fixed-bed reactor is connected to the low-boiling material inlet. The second distillation column has a high-boiling material inlet and a top outlet, and the bottom outlet of the stripping section is connected to the high-boiling material inlet. The first outlet and the top outlet of the second distillation column are respectively connected to an adsorption column.

The application relates to a method for synthesizing and refining electronic-grade hexachloroethyldisilane, and specifically, trichlorosilane raw material is mixed with protective gas into a raw material buffer tank, a mixed gas obtained through the mixing is subjected to a catalytic synthesis reaction under the irradiation of an ultraviolet light source, a product obtained through the reaction is subjected to condensation separation, gaseous trichloromethane returns to the raw material buffer tank to continuously participate in the synthesis reaction, the mixed liquid in the cold trap is warmed and vaporized, hexachloroethyldisilane is obtained through two-step refining, and the purity of the product hexachloroethyldisilane can reach the electronic grade. The application takes trichlorosilane as the initial raw material, the price of the raw material is low; the photo-catalysis is used as the synthesis process, the synthesis process is simple, the reaction yield is high, energy is saved, and the environment is protected; the two-step method is used for refining and purifying the product, the depth of the refining and the efficiency of the refining are high, large-scale production is suitable, the monopoly of foreign enterprises is broken, and the application has important significance.

The invention provides a method for recovering tail gas generated in production of carbon nanotubes. The method comprises the following steps: compression: introducing tail gas containing methane and hydrogen into a compressor for pressurization; first-stage separation: the pressurized tail gas is introduced into a first-stage membrane separator for separation, methane and first-stage tail gas are obtained, and the main component of the first-stage tail gas is hydrogen; and second-stage separation: introducing the first-stage tail gas into a second-stage membrane separator for separation to obtain hydrogen and second-stage tail gas containing hydrogen. Through two-stage membrane separation, methane and hydrogen are recovered, the methane separated in the first stage can return to the continuous furnace to be continuously used as a raw material for producing carbon nanotubes, and the hydrogen separated in the second stage can be used for producing trichlorosilane, so that the recovery and utilization of resources can be realized.

A halotrisilane preparation method may include providing a reactant that contains halotrisilane including M halogen atoms (where, M may be a natural number from 2 to 8), reducing the halotrisilane in the reactant by using a mixed reducing agent that includes a first reducing agent represented by Formula 1-1 and a second reducing agent represented by Formula 2-1, and obtaining a product that contains the reduced halotrisilane that includes N halogen atoms, where N may be a natural number from 1 to 7 and where N<M.(RA)a-Al-Hb[Formula⁢ 1-1]In Formula 1-1 above, RA may represent an alkyl group, a and b each may be either 1 or 2, and a+b=3.(RS)p-Sn-Hq[Formula⁢ 2-1]In Formula 2-1 above, RS may represent an alkyl group or an aryl group, p and q each independently may be a natural number from 1 to 3, and p+q=4.

The present invention provides a hydrotalcite adsorbent, a preparation method thereof, and an application thereof in the purification of chlorosilanes. The preparation method includes: S1 preparing a metal salt solution and a first alkali solution respectively; S2 synthesizing a magnesium-zinc-aluminum hydrotalcite; S3 synthesizing a magnesium-zinc-aluminum composite metal oxide; S4 synthesizing a hydrotalcite adsorbent. In the present invention, a magnesium-zinc-aluminum ternary hydrotalcite is first prepared by the nucleation / crystallization isolation method, and then a hydrated-reduced magnesium-zinc-aluminum hydrotalcite with a large specific surface area, good stability, a wide pH application range, and rich Bronsted basic sites is obtained through a calcination-hydration reduction method. When it is applied to the reaction of chlorosilane adsorption and purification, the effective removal of boron and phosphorus impurities can be achieved. The present invention provides a preparation method of a hydrotalcite adsorbent and expands the application of the hydrotalcite adsorbent in the field of chlorosilanes.

The utility model provides a liquid removing device externally arranged on a silicon tetrachloride vaporizer, and aims to solve the technical problem that liquid is contained in a medium after silicon tetrachloride is vaporized in the prior art. The liquid removal device comprises: a tank body having an inlet, an outlet and an inspection port; the defoaming net is arranged in the middle of the tank body and located between the inlet and the outlet, and the interior of the tank body is divided into two spaces by the defoaming net; the blind plate covers the inspection opening; wherein the inlet is located at the bottom of the tank body, and the outlet is located above the inlet. The inlet of the tank body is connected with the outlet of the vaporizer, a medium obtained after vaporization of silicon tetrachloride needs to penetrate through the defoaming net, and liquid carried in the medium can be separated through the defoaming net. Besides, the inlet of the tank body is arranged at the bottom of the tank body, so that the separated liquid can fall into the vaporizer again under the influence of gravity for vaporization. According to the technical scheme, the influence on the production quality of polycrystalline silicon in the reduction furnace can be avoided, and the production energy consumption of the polycrystalline silicon is reduced.

The utility model provides a trichlorosilane purification device in a polycrystalline silicon production process, which belongs to the technical field of trichlorosilane purification devices and comprises a distillation component, the distillation component comprises a distillation barrel, a heating barrel is mounted in the distillation barrel, a top cover is mounted at the top of the distillation barrel, a first gas guide pipe is mounted on the surface of the top cover, and a second gas guide pipe is mounted on the surface of the top cover. A first gas guide pipe is mounted at one end of the heating barrel, a transfer barrel is mounted on the surface of the other end of the first gas guide pipe, a second gas guide pipe is mounted on one side of the bottom of the transfer barrel, a stirring rod is rotatably connected to the interior of the heating barrel, and a plurality of scrapers are mounted on the surface of the stirring rod. According to the method, the purity of trichlorosilane is improved, so that the quality and the purity of a polycrystalline silicon product are improved, meanwhile, impurities and wastes can be separated, the workload of subsequent treatment is reduced, the production efficiency is improved, the energy consumption and the production cost can be reduced, and the resource utilization rate is improved.

The utility model provides an impurity removal system for preparing disproportionation reaction silane gas, which comprises a dehydrogenation tower (1) for preparing silane, and further comprises a side production pipeline (5) arranged in the middle of the side of the dehydrogenation tower (1), the other end of the side production pipeline (5) is in fluid connection with a circulating water condenser (6), and the other end of the circulating water condenser (6) is in fluid connection with the dehydrogenation tower (1). A liquid phase outlet of the circulating water condenser (6) is in fluid connection with a buffer tank (7), and the buffer tank (7) is in fluid connection with a silane reaction tower (9) through a pump (8). According to the device, the content of heavy phosphorus impurities in silane gas can be reduced, and the quality of the product silane gas is improved; the dehydrogenation tower is transformed to reduce the influence of phosphorus impurities on the activity of the catalyst in the reaction tower.