214results about "Preparation from chlorides" patented technology

The invention provides an electro / thermochemical gradient hydrogen production system and method for solar radiation energy grading and residual light energy thermal complementary coupling. The system comprises a light condensation assembly; the frequency division assembly is used for grading solar spectrum radiation; a photovoltaic cell power generation device; the methane oxygen-enriched combustion high-temperature photovoltaic power generation device is used for realizing oxygen-enriched combustion of natural gas by utilizing residual heat heat energy and generating power by utilizing radiation energy generated by high-temperature flue gas generated after combustion; the solid oxide electrolytic tank device is used for pushing solid oxide to electrolyze water to produce hydrogen by utilizing heat energy and electric energy contained in the high-temperature flue gas step by step; and the thermal chemical reaction device is used for promoting each step of thermal chemical reaction by utilizing heat energy and electric energy contained in the high-temperature flue gas step by step. The energy source of the system is solar radiation and natural gas, hydrogen and electricity are produced, the system utilizes different energy conversion modes to achieve temperature gradient ordered conversion and utilization of residual light energy after solar frequency division, and complementary coupling of different qualities is achieved on the basis of energy gradient conversion.

The utility model relates to a system for preparing electronic-grade hydrochloric acid by using a Mannheim device. Comprising a potassium chloride storage tank, a desalted water pipeline and a concentrated sulfuric acid storage tank, the potassium chloride storage tank and the concentrated sulfuric acid storage tank are respectively connected with a Mannheim furnace, a byproduct hydrogen chloride gas pipeline of the Mannheim furnace is connected with a B acid washing tower, a gas pipeline in the B acid washing tower is connected with an A acid washing tower, and a gas pipeline in the A acid washing tower is connected with an inlet of a drying tower; a spraying pipeline at the upper part in the drying tower is connected with a concentrated sulfuric acid storage tank; a gas phase outlet of the drying tower is connected with an electronic-grade hydrochloric acid storage tank through a gas purifying and absorbing unit and a filtering unit in sequence; a bottom liquid phase outlet of the drying tower is connected with a concentrated sulfuric acid inlet of the Mannheim furnace; the method has the advantages of improving the added value of products and reducing the production cost.

The invention belongs to the technical field of aluminum electrolysis waste treatment, and particularly relates to a method for green recovery of aluminum electrolysis waste. The method comprises the following steps: mixing and roasting aluminum electrolysis waste, aluminum-containing waste and sulfuric acid to prepare modified waste; the modified waste is smashed and stirred, and filter residues A and filtrate A are filtered and separated out; removing impurities from the filtrate A to obtain filter residues B and filtrate B; reacting the filtrate B with water-soluble carbonate or phosphate to prepare a lithium product; mixing and roasting the filter residue A, the filter residue B and a silicon-containing substance to generate aluminum oxide and silicon tetrafluoride gas; dissolving the aluminum oxide through hydrochloric acid, and reacting the silicon tetrafluoride gas with an aluminum chloride solution to form silicon tetrachloride gas and aluminum fluoride; the silicon tetrachloride gas is combusted to generate hydrogen chloride gas and silicon dioxide particles, and the hydrogen chloride gas is converted into a hydrochloric acid solution through water absorption. According to the method, recycling of aluminum and lithium resources in the aluminum electrolysis waste is effectively achieved, by-products are converted into valuable chemical substances, and resource recycling is promoted.

The present invention provides a fluidized bed catalyst composition, which includes a catalyst A and a catalyst B, wherein the catalyst A and the catalyst B respectively include a carrier and an active component, wherein the active component of the catalyst A includes a copper element, an alkali metal element and a rare earth element; the carrier of the catalyst B is alumina, and the active component includes a copper element, an alkali metal element and a rare earth element; by weight, the rare earth element content of the catalyst B is 1.1-20 times the rare earth element content of the catalyst A; and the weight ratio of the catalyst A to the catalyst B is 1-100: 1. The catalyst composition of the present invention can be directly applied to a fluidized bed reactor to catalyze the oxidation of hydrogen chloride to prepare chlorine without defluorination treatment on the basis of a high concentration of fluorine-containing compounds in the hydrogen chloride raw gas.

The invention discloses a casing tubular reactor for preparing chlorine by oxidizing hydrogen chloride, which comprises a main body, and a lower seal head and an upper seal head which are respectively arranged at the bottom end and the top end of the main body, a casing reaction tube is arranged in the main body, and the casing reaction tube comprises a central tube and a jacket which is arranged on the outer wall of the central tube in a surrounding manner. A heating medium flows through the central pipe and the jacket, so that the heat exchange area is increased, and the heating medium is timely moved away from the reactor to take away heat generated by heat release of oxidation reaction, so that excessive concentration of bed reaction heat is avoided; and the obvious defect of traditional reaction equipment in the aspect of heat removal is overcome, the problems that the reaction efficiency is limited and the energy consumption is high are solved, and the reaction efficiency can be greatly improved. The invention also provides a system and a method for preparing chlorine by oxidizing hydrogen chloride, which realize recycling of reaction heat, reduction of energy consumption, recycling of tail gas discharged from an absorption tower after treatment, improvement of the utilization rate of raw materials, closed-loop operation of chlorine elements and reduction of the production cost.

The invention relates to a comprehensive utilization major cycle process in cooperative treatment of industrial flue gas pollutants, which comprises the following steps: removing SO2 and NOx in flue gas by adopting an adsorption method, and desorbing SO2 and NOx by adopting a water solution method to generate sulfuric acid and nitric acid; sulfuric acid reacts with sodium chloride to produce hydrochloric acid; sulfuric acid, nitric acid and hydrochloric acid are combined into a composite acid solvent, the solvent dissolves aluminum oxide in the fly ash to be converted into polybasic acid aluminum, the polybasic acid aluminum is subjected to ammonification decomposition into aluminum hydroxide and composite acid ammonium, the composite acid ammonium reacts with calcium carbonate to generate NH3, CO2 and polybasic acid calcium, and the polybasic acid calcium reacts with sodium sulfate to generate nano calcium sulfate; the method comprises the following steps: reacting silicon dioxide with sodium hydroxide to generate sodium silicate, reacting sodium silicate with sodium bicarbonate to generate silicic acid and sodium carbonate, reacting sodium carbonate with calcium hydroxide to generate calcium carbonate and sodium hydroxide, and mixing multi-element metal oxide separated from aluminum and silicon extraction with silicon dioxide and aluminum hydroxide which are separated and carried to prepare a multi-element cation molecular sieve; and comprehensive utilization and large circulation of the flue gas pollutants are realized through the synergistic effect of the pollutants.

The invention discloses a comprehensive utilization method of refining slag, which comprises the following steps: dissolving the refining slag in hydrochloric acid to obtain a refining slag pickle liquor; filtering the refining slag pickle liquor to obtain first filtrate and filter residues, and washing the filter residues to obtain first solid and first washing liquor; combining the first washing liquid and the first filtrate to obtain a second mixed solution; and adding an oxidizing agent into the second mixed solution to obtain a first precipitate. According to the method, the refining slag is subjected to acid leaching with hydrochloric acid, the PH value of the solution is adjusted, silicon dioxide, aluminum hydroxide, ferric hydroxide, calcium chloride or calcium oxide and recycled hydrochloric acid are obtained, the accumulated refining slag is decomposed into various new substances in the process reaction, the method is simple, the substance purity is high, the refining slag is recycled, and large economic value can be created; and meanwhile, mining of various resources is reduced. And a new direction is found for comprehensive utilization of the refining slag.

The invention relates to a preparation method of a high-capacity silicon-carbon composite negative electrode material, which comprises the following steps: preparation of electronic-grade hydrochloric acid, preparation of a photovoltaic waste silicon powder ball mill, preparation of a silicon-coated calcium carbonate core-shell structure material, preparation of a gradient carbon coating layer, synthesis preparation of a carbon nanotube conductive network, preparation of a graphene nanobelt silicon-carbon composite material and the like. The preparation method creatively combines a two-step electrostatic attraction self-assembly method, a high-temperature oxidation process and other preparation methods, the prepared silicon-carbon composite material shows stable cycle performance and high capacity performance, and the silicon-carbon composite material has the advantages of high specific capacity and low impedance.

The utility model belongs to the field of chemical raw material recovery, and discloses a system for separating salt and extracting bromine from purified terephthalic acid membrane concentrated water. The system comprises a thermal decomposition device, a nanofiltration device, a static mixer and a bromine extraction rectification device. The utility model solves the technical problems that the acid consumption is large before bromine is extracted from purified terephthalic acid wastewater, and poisoning is easily caused by leakage hidden danger in the transportation and storage process of liquid chlorine.

The invention provides a Cu-based catalyst for preparing chlorine through catalytic oxidation of hydrogen chloride and a preparation method and application of the Cu-based catalyst, the catalyst takes aluminum oxide as a carrier, the catalyst contains 2-10 wt% of Cu, 0.0001-0.5 wt% of S and 0.0001-0.5 wt% of P, the Cu content of the unit specific surface area of the catalyst is 1-50 * 10 <-4 > g / m < 2 >, and the conductivity of the catalyst dispersed in water with the same mass is 1-100 mS / cm. Although the Cu loss sign exists in the use process of the catalyst, the Cu content of the unit specific surface area of the catalyst does not decrease along with the extension of the reaction time, so that the activity is maintained. The catalyst provided by the invention overcomes the phenomenon of activity decline caused by Cu loss in the long-time use process, can realize industrial long-period stable operation, and has very high application value.

Embodiments of the present disclosure are directed to systems and methods of removing carbon dioxide from a gaseous stream using magnesium hydroxide and then regenerating the magnesium hydroxide. In some embodiments, the systems and methods can further comprise using the waste heat from one or more gas streams to provide some or all of the heat needed to drive the reactions. In some embodiments, magnesium chloride is primarily in the form of magnesium chloride dihydrate and is fed to a decomposition reactor to generate magnesium hydroxychloride, which is in turn fed to a second decomposition reactor to generate magnesium hydroxide.

The embodiment of the invention relates to the field of separation by using a physical or chemical method, in particular to chloride molten salt purification equipment and a purification method. The chloride molten salt purification equipment comprises a containing part maintaining assembly, a purification furnace body, a purification furnace cover body, a furnace cover movement mechanism and a purification moving assembly. The accommodating part holding assembly is used for holding a plurality of molten salt accommodating parts; the purification furnace cover body is used for opening or closing a top opening of the purification furnace body and forms a reaction space together with the purification furnace body; the furnace cover movement mechanism is used for driving the purification furnace cover body to lift and rotate, so that the top opening is completely opened or closed; the purification moving assembly is used for driving the containing part maintaining assembly to move in the reaction space, and when the top opening is completely opened, the purification moving assembly drives the containing part maintaining assembly to move to protrude out of the top opening. According to the chloride molten salt purification equipment provided by the embodiment of the invention, the discharging efficiency and the feeding efficiency of the chloride molten salt after the chloride molten salt is purified can be improved.

The present application relates to a kind of catalyst for hydrogen chloride oxidation preparation chlorine and its preparation method and application.The preparation method includes: after carrier substrate, metal tantalum powder, binder solution are mixed, extrusion forming is obtained green body, the green body is prepared composite carrier by calcination, the mass fraction of metal tantalum powder in the composite carrier is 5%-30%;Inorganic salt containing catalytically active element is made into solution and is placed in the composite carrier, and after drying, pre-product is obtained, and the pre-product is prepared catalyst by calcination.The preparation method described in the present application prepares high thermal conductivity composite carrier, not only effectively improves the heat conduction efficiency of catalyst, guarantees the effective activity of catalyst, but also guarantees the stability of composite carrier, thereby effectively prolongs the life of catalyst.

The utility model relates to a wastewater treatment and recovery device. The wastewater treatment and recovery device comprises a first recovery assembly and a second recovery assembly, the first recovery assembly comprises a first storage tank, a second storage tank, a first connecting pipeline, a second connecting pipeline and a first reaction kettle, the first reaction kettle comprises a first reaction kettle body, the first storage tank is communicated with the first reaction kettle body through the first connecting pipeline, and the second storage tank is communicated with the first reaction kettle body through the second connecting pipeline. The second recovery assembly comprises a third connecting pipeline, a second reaction kettle and an evaporative crystallization structure, the second reaction kettle comprises a second reaction kettle body, the second reaction kettle body is communicated with the first reaction kettle body through the third connecting pipeline, and the evaporative crystallization structure is communicated with the second reaction kettle body. According to the technical scheme, the problem that in the prior art, the recycling rate of recoverable components in waste water raw materials is low is effectively solved.

The invention discloses a production method and a production system of high-purity phosphorus trifluoride and hydrogen chloride, and belongs to the field of preparation of phosphorus trifluoride and hydrogen chloride. The production method comprises the following steps: reacting phosphorus trichloride with anhydrous hydrogen fluoride to generate phosphorus trifluoride and hydrogen chloride, condensing at-20 DEG C to 0 DEG C, refluxing phosphorus trichloride and hydrogen fluoride raw materials, and outputting mixed gas of phosphorus trifluoride and hydrogen chloride; preliminarily rectifying the mixed gas to obtain a phosphorus trifluoride crude product and a hydrogen chloride crude product; the method comprises the following steps: carrying out primary rectification on a phosphorus trifluoride crude product in a phosphorus trifluoride rectification heavy component removal tower and carrying out secondary rectification in a phosphorus trifluoride rectification light component removal tower in sequence to obtain high-purity phosphorus trifluoride gas; the crude hydrogen chloride is subjected to primary rectification in a hydrogen chloride rectification heavy component removal tower and secondary rectification in a hydrogen chloride rectification light component removal tower in sequence, and high-purity hydrogen chloride gas is obtained. According to the production method, high-purity phosphorus trifluoride and high-purity hydrogen chloride can be continuously produced and obtained, meanwhile, the raw material utilization rate can be increased, the product yield can be increased, meanwhile, little waste gas is generated, the waste gas can be completely absorbed, and the requirement for environmental protection is met.

The invention discloses a hydrogen chloride gas absorption device-modified double-path pure water absorption system and a process method, and relates to the technical field of chemical waste gas treatment and resource recovery. The device comprises a hydrochloric acid synthesis furnace, a first-stage falling film absorber, a second-stage falling film absorber, a combined tail gas absorption tower and a tail gas purification unit which are sequentially connected, as well as a pure water supply system and an automatic control system. The system is characterized in that the pure water supply system is divided into two independent branches through a water inlet header pipe to be connected to the combined tail gas absorption tower, and each branch is provided with an automatic regulating valve. According to the method, a traditional single-path water absorption system is transformed into a double-path standby system through low-cost technical improvement of an existing single-path absorption device, automatic and rapid switching to the other path when one path breaks down is achieved, and therefore the problems that in the prior art, production is discontinuous, product concentration fluctuation is large, and potential safety hazards exist are effectively solved; the effects of efficiently, continuously and safely producing high-concentration hydrochloric acid and realizing near-zero emission of tail gas are achieved.

The invention discloses a ferric chloride low-temperature solid-phase oxidation method which comprises the following steps: carrying out microwave pretreatment on a ferric chloride solid raw material, and heating the ferric chloride solid raw material to 80-120 DEG C to obtain preheated and activated ferric chloride; oxygen is preheated to 250-300 DEG C and then subjected to a low-temperature oxidation reaction with preheated and activated ferric chloride, the temperature of the low-temperature oxidation reaction is 200-320 DEG C, crude iron oxide and chlorine are obtained, and the crude iron oxide is a mixture of mica iron oxide and ferric chloride; and heating and separating ferric chloride in the crude iron oxide to obtain a mica iron oxide product. The ferric chloride raw material is preheated and activated through the microwave pretreatment technology, the activation energy of the oxidation reaction is reduced, and then the temperature range required by raw material preheating is reduced, so that the solid-phase oxidation reaction can be carried out at a relatively low temperature; therefore, the heating energy consumption is greatly reduced on the premise of ensuring high product yield and purity, the generated three wastes are few, and the method is green and environment-friendly.

A method of treating a brine composition includes hydrolyzing a metal halide salt in the brine composition to form a hydrolysis product including a hydrohalic acid. The metal includes an alkaline earth metal or an alkali metal.

The present invention provides a metal-supported composite molecular sieve catalyst and a preparation method and application thereof, and relates to the technical field of catalyst preparation. The present invention improves the carrier, adopts a high temperature resistant ZSM-5 molecular sieve or SSZ-13 molecular sieve with a large specific surface area, and combines it with γ-Al 2 O 3 The composite is used as a carrier, so that the carrier has a large specific surface area, strong loading capacity, high chemical stability and adsorption capacity, so that the catalytic reaction is more complete, the loss of active components is reduced, and the stability of the catalyst is improved. The experimental results show that when the catalyst prepared by the present invention catalyzes hydrogen chloride to produce chlorine, the chlorine yield after 8 hours of reaction is 87.8-96.28%, and the chlorine yield after 1000 hours of reaction is 86.9-96.11%.

The invention relates to a method for preparing chlorine by using hydrogen chloride and oxygen, which belongs to the technical field of treatment and utilization of hydrogen chloride, and comprises the following steps: step 1, mixing hydrogen chloride gas and oxygen, inputting the mixture into a reactor filled with a copper-based catalyst at the temperature of 260-400 DEG C and the pressure of 0-1.0 MpaG, and carrying out catalytic oxidation on the hydrogen chloride gas to form chlorine and water vapor; and 2, separating water vapor, incompletely reacted hydrogen chloride gas and oxygen, and rectifying to obtain liquid chlorine, namely cooling in a quench tower and absorbing hydrogen chloride, absorbing water vapor in a drying tower, and separating oxygen in a chlorine rectifying tower to obtain liquid chlorine. After the copper-based catalyst is used, the reaction air speed is high, the space time yield (STY) is larger than 5.6 gcl2 / gcat.h, the hydrogen chloride conversion rate is larger than or equal to 93 wt%, the hydrogen chloride conversion rate is high, the catalyst dosage is small, the cost of the copper-based catalyst is lower, and the whole technological process is short, low in energy consumption and low in operation cost.

The invention discloses a green synthesis method of electronic-grade methylsilane and hydrogen chloride based on an ionic liquid catalyst, belongs to the technical field of synthesis of organosilicon compounds and high-purity electronic special gases, and discloses a green synthesis method of electronic-grade methylsilane and hydrogen chloride based on an ionic liquid catalyst. Comprising the following steps of S1, catalyst preparation, S2, methylsilane and hydrogen chloride preparation, S3, product purification and S4, activated carbon regeneration, 1-ethyl-3-methylimidazole aluminum chloride as the catalyst has good thermal stability and catalytic activity, the risk of catalyst inactivation is avoided, the catalyst can be pumped into a reaction kettle, the whole process is operated in a closed mode, and operation is easy. The method is safe, reliable and environment-friendly, and meanwhile, regeneration and recycling of the activated carbon bring a better use prospect.

In some embodiments the application pertains to processes comprising reacting a component comprising an alkaline earth weak acid with a component comprising an acid to form a component comprising an alkaline earth acid anion and a component comprising a weak acid derivative. At least a portion of the component comprising the alkaline earth acid anion is reacted with a component comprising an alkali sulfate to form a component comprising alkaline earth sulfate and a component comprising an alkali acid anion. At least a portion of the component comprising alkaline earth sulfate is decomposed to form a component comprising alkaline earth oxide, or alkaline earth hydroxide, or alkaline earth carbonate, or alkaline earth sulfide, or a derivative thereof, or any combination thereof, and a component comprising sulfur dioxide, or oxygen, or sulfur trioxide, or a derivative thereof, or any combination thereof.

The present invention relates to a process for producing isocyanates and, optionally, polyurethanes, by at least synthesizing (1) phosgene (20) from carbon monoxide (21) and chlorine (22); reacting (2) phosgene (20) with a diamine (23) to produce a diisocyanate (24) and hydrogen chloride (25); providing a carbon dioxide gas stream (31); and cleaning (4) the carbon dioxide gas stream (31) with additional components, wherein the carbon dioxide is converted by a RWGS reaction (6) to produce carbon monoxide (21) and hydrogen (29), which are used as raw materials for polyurethane production, and optionally reacting (3) the diisocyanate (24) with a polyether polyol (35a) and / or polyester polyol (35b) to produce polyurethane (37).

This invention provides a method for preparing a platinum-ruthenium catalyst for chlorine production, comprising: mixing nitrosylruthenium nitrate, platinum nitrate solution, deionized water, and a dispersant; heating to reflux temperature to dissolve; continuing the reaction at reflux temperature for 1 hour after the system changes from brownish-red to brownish-black; filtering the system after cooling to room temperature; and mixing the platinum-ruthenium mixture, silica hydrosol, and silica powder. The mixture is extruded into cylindrical pieces with a diameter of 5 mm, dried at 100-120°C for 6 hours to a breakage length of approximately 3-5 mm, and calcined in air at 200-240°C for 12 hours to obtain the platinum-ruthenium catalyst. This method can prepare a platinum-ruthenium catalyst with low chlorine impurity content that easily leads to catalyst aging. Simultaneously, because the reaction system remains acidic, the occurrence of ruthenium hydrolysis side reactions is reduced, resulting in a platinum-ruthenium catalyst with high yield, high ruthenium dispersion, and high catalyst activity.

The invention discloses an extraction and separation method for recycling low-concentration ammonia water and hydrochloric acid, which comprises the following steps: saponifying an acidic extractant, extracting and separating the saponified extractant from a mixed metal chloride solution to generate a loaded organic phase and a low-concentration ammonium chloride solution, reextracting the loaded organic phase with diluted hydrochloric acid after extraction and separation, and separating the low-concentration ammonium chloride solution from the loaded organic phase. A grouped or single metal chloride solution is obtained; the low-concentration ammonium chloride wastewater is subjected to oil removal treatment and metal impurity ion removal treatment to obtain a purified ammonium chloride solution; separating the purified ammonium chloride solution to obtain diluted hydrochloric acid, diluted ammonia water and light salt brine; diluted hydrochloric acid is used for back extraction or dissolution of an extracted component precursor, diluted ammonia water is reused for saponification of an acidic extractant, and low-salt fresh water generated by a BMED system is returned to an extraction washing section for enrichment and regeneration or concentrated hydrochloric acid diluent. The invention solves the problem of recycling low-concentration ammonia water / hydrochloric acid.

The invention discloses a method for comprehensively recycling high and low boiling residues and waste acid in the production process of high-purity antimony, and relates to the field of non-ferrous metal metallurgy. The method comprises the following steps: mixing high and low boiling residues produced in the preparation process of high-purity antimony with waste acid produced by cleaning equipment, spraying the mixed solution into a roasting tower through compressed air for roasting, and enabling roasted flue gas to sequentially pass through a settling chamber, a bag collector and a two-stage water spraying absorption tower to respectively produce antimony white and hydrochloric acid, the produced antimony white can be directly sold or used as an antimony smelting raw material, and the byproduct hydrochloric acid can be used as an acid for wet smelting or can be further concentrated into 35-38% concentrated hydrochloric acid. The method can realize gradient recycling of antimony and chlorine elements in the high and low boiling residues and the waste acid, has the characteristics of high resource utilization level and no generation of a large amount of wastewater, and has good economic value and environmental protection benefit.

The utility model discloses a treatment system for industrial mixed waste salt containing sulfate, which includes an adsorption and impurity removal unit, an acid dechlorination unit and a convection chemical unit. The industrial mixed salt is first pretreated by a pretreatment unit to remove the organic matter contained therein, and then the chlorine element is removed by acid dechlorination in the acid dechlorination unit by adding a strong acid, and finally the sulfate solution and the barium sulfide solution are prepared by convection spraying in a high-efficiency chemical reaction device of the convection chemical unit to obtain a high-purity, high-value nano-barium sulfate product and a high-purity, high-value sodium sulfide product with uniform particle size distribution, and finally the high resource utilization of industrial mixed salt is realized. The system of the utility model has the characteristics of simple structure, strong operability and low equipment investment cost, and can realize large-scale industrial application.

The utility model relates to the technical field of chemical gas recovery, and provides a device for separating trichlorosilane tail gas and co-producing fumed silica, which adopts a combined process to treat the trichlorosilane tail gas and is provided with a rectification separation seat provided with a low-temperature cold energy recovery mechanism. Hydrogen, hydrogen chloride and chlorosilane in the tail gas are separated step by step through the rectification separation assembly, the hydrogen chloride and the chlorosilane are directly conveyed to the combustion assembly, the purity of the hydrogen chloride is recycled to the trichlorosilane tail gas treatment assembly, recycling after separation is achieved, and the purposes of further saving energy consumption and improving the purity are achieved; a fumed silica combustion furnace suitable for low-boiling-point chlorosilane is adopted, so that the chlorosilane and hydrogen are mixed and combusted to generate fumed silica and hydrogen chloride, and the fumed silica can be directly discharged through a fumed silica discharge pipe; and the generated hydrogen chloride is recovered into the trichlorosilane tail gas treatment seat through a second hydrogen chloride return pipe, and closed-loop utilization is realized.

The present invention relates to the technical field of silica sol preparation, and in particular to a method for preparing high-purity silica sol and hydrogen chloride, comprising the following steps: adding a higher alcohol to a reactor, heating to melt the higher alcohol; adding silicon tetrachloride to the reactor, fully reacting silicon tetrachloride with the molten higher alcohol to generate silicate and hydrogen chloride, during the reaction, the higher alcohol and the generated silicate are kept in a heated and melted state, and the hydrogen chloride is discharged from the reactor in the form of gas and collected; the substances in the reactor are kept in a heated and melted state, and an excess of water is added to the reactor to completely hydrolyze the silicate to generate silica hydrosol and higher alcohol; cooling the reactor until the higher alcohol is converted into a solid state and the silica hydrosol remains in a liquid state; and separating the liquid silica hydrosol from the solid higher alcohol. The method for preparing high-purity silica sol of the present application has the advantages of preparing ultra-high purity silica sol and separating hydrogen chloride at a low cost.