1028results about "Chlorine/hydrogen-chloride purification" patented technology

A process for regenerating a used acidic catalyst which has been deactivated by conjunct polymers by removing the conjunct polymers so as to increase the activity of the catalyst is disclosed. Methods for removing the conjunct polymers include hydrogenation, addition of a basic reagent and alkylation. The methods are applicable to all acidic catalysts and are described with reference to certain ionic liquid catalysts.

According to the first characteristic of the present invention, there is provided a production process for 1,3,3,3-tetrafluoropropene including: the first step of reacting 1,1,1,3,3-pentachloropropane with hydrogen fluoride thereby obtaining 1-chloro-3,3,3-trifluoropropene; and the second step of reacting 1-chloro-3,3,3-trifluoropropene obtained in the first step with hydrogen fluoride in a gaseous phase in the presence of a fluorination catalyst. According to the second characteristic of the present invention, there is provided a dehydration process including bringing 1,3,3,3-tetrafluoropropene containing at least water into contact with zeolite.

The invention discloses a method for recycling hydrogen chloride in tail gas of polysilicon production. In the method, tail gas is cooled and condensed, so that most of chlorosilane is liquefied; compressed gas enters a hydrogen chloride absorption tower and absorbed by chlorosilane solution, and hydrogen gas is exhausted from the hydrogen chloride absorption tower and collected; liquid hydrogen-chloride-rich chlorosilane discharged from the bottom of the hydrogen chloride absorption tower is introduced into a hydrogen chloride distillation tower, and chlorosilane solution is discharged form the bottom of the hydrogen chloride distillation tower; and hydrogen chloride containing trace hydrogen gas is exhausted from the top of the hydrogen chloride distillation tower and enters a full condenser on the top of the distillation tower, condensate of the full condenser on the top of the distillation tower enters a return tank of the distillation tower, the trace hydrogen is exhausted from the top of the return tank of the distillation tower and collected, a part of the condensate of the return tank of the distillation tower is introduced into the hydrogen chloride distillation tower and used as return liquid, and the other part of the condensate enters a liquid hydrogen chloride reservoir for storage. The method improves the purity of recycled hydrogen chloride and the storage amount of hydrogen chloride and saves the investment of equipment.

The invention discloses a method of extractive purifying industrial alcaine, which comprises the following steps: setting triallylamine as extractant, isooctanol as assisting solvent and coal oil as diluent; forming extract organic phase through kerosene; extracting industrial alcaine in the extract pot; washing through pure water; stripping; getting high-purity alcaine. The invention possesses steady quality and high-purity, which can realize continuous mass production.

The invention relates to a processing method of thionyl chloride acyl-chlorinated tail gas. Mixed tail gas produced by a acyl chlorinating process contains hydrogen chloride and sulfur dioxide; the sulfur dioxide is liquefied under a certain temperature condition; the incondensable hydrogen chloride and a little sulfur dioxide are absorbed in two stages by water; the absorbed tail gas in a first stage is pure hydrogen chloride gas; after being absorbed in a second stage, the qualified chlorhydric acid is obtained; first-stage falling film absorption liquid is resolved by heating; then the tail gas is sent to a liquefying process again; the liquid sulfur dioxide can be canned as a product; or after being vaporized, the liquid sulfur dioxide is absorbed by 30 percent of sodium hydroxide solution to obtain sodium sulfite aqueous solution which is further dried after low temperature crystallization or distillation to obtain 97 percent of sodium sulfite solid. With the method, the hydrogen chloride, the sulfur dioxide and a little thionyl chloride produced by an acyl chlorination synthetic process can be separated out to obtain the chlorhydric acid and the pure sodium sulfite solid. The processing method of the thionyl chloride acyl-chlorinated tail gas of the invention is capable of effectively recovering the thionyl chloride acyl-chlorinated tail gas, which has the advantages of safety process and easy control.

This invention relates to a method for separating and purifying mixing exhaust gas of chlorine and hydrochloride, comprising: absorb the chlorine in the mixing exhaust gas using solvent A to separate from gas phase hydrochloride, the chlorine can be obtained after solvent A desorption, the hydrochloride can be obtained by removing solvent A in the gas phage hydrochloride using solvent B, wherein: solvent A is one of benzene, silicon tetrachloride, nonyl hydride, sulfur monochloride, carbon tetrachloride and chlorosulfonic acid, and solvent B is one of cyclopentadiene and hexachlorobutadiene. By washing with concentrated hydrochloric acid to remove trace amount of organic compounds, and chemical washing to remove heavy metal elements, the hydrochloride is absorbed by water to make hydrochloric acid. This invention is characterized of efficient separation of chlorine and hydrochloride, high efficiency of separation, low cost, high-usage of resources, high purity of chlorine up to 99%, recycling use, and the purity of hydrochloride meets the requirement of producing industrial hydrochloride and hydrochloride regent .

This invention describes a hydrometallurgical process for the recovery and separation of valuable elements, in particular gold and silver, from a feed material comprising a refractory, intractable or otherwise poorly responding to conventional treatment routes ores, concentrates and other materials. In particular, the process is a process integrated into one or more existing value element extraction processes.

Provided is a novel method and system for preparing ultra-high-purity buffered-hydrofluoric acid or ammonium fluoride controlled concentration. The method comprises bubbling purified ammonia vapor into ultra-pure hydrofluoric acid. The inventive method and system can be used as an on-site subsystem in a semiconductor device fabrication facility for supplying the buffered-hydrofluoric acid and ammonium fluoride to points of use in the semiconductor device fabrication facility.

Disclosed is a method which recovers pure acid from the waste acid contains metallic ion and reproduces alkaline, and belongs to the environmental protection field. The process steps include that: (a) the waste acid solution with the acid concentration 10%-40% is processed with the first level diffusion dialysis; (b) the residue after the step a is processed with the second level diffusion dialysis; the volume ratio of the first level (or the second level) waste acid (or the first level diffusion residue) in the first level (or the second level) diffusion dialysis groove residue and the acid recovery chamber collected solution is 1:0.5-1:3.0; the flow rate of the waste acid (or the first level diffusion residue) is enabled to be 0.2-0.6L/h; the flow rate of the acid recovery chamber collected solution is 0.1-1.8L/h; (c) the second residue after the step b is processed with neutralization and deposition; (d) the neutralized filtrate after the solid-liquid separation-filtration is fed to the three compartment electrodialysis groove middle chamber, the electrodialysis is processed for 1-3h under the voltage 5-15V to obtain the reproduction acid and reproduction alkaline. The method which recovers pure acid from the waste acid contains metallic ion and reproduces alkaline has the advantages of high acid recovery rate, low production cost and energy-consumption, less film pollution, saving water, reducing discharge and no secondary pollution.

The invention disclosed a porous solid supported ionic liquid and application thereof in adsorption of HCl gas, the porous solid supported ionic liquid comprises a porous solid support and an ionic liquid supported on the support, the porous solid support is activated carbon, mesoporous carbon, carbon nanotubes, silicon oxide, aluminum oxide, titanium oxide, a molecular sieve, a metal organic framework compound or a covalent organic framework compound; the ionic liquids is imidazole, pyridine, quaternary phosphonium and pyrrolidinium ionic liquid, the Ionic liquid loading amount is 1 to 50% based on the mass of the porous solid support. The porous solid supported ionic liquid can be used for adsorbing of the HCl gas, and is used in typical occasions for adsorbing of the HCl gas in industrial exhaust gas of vinyl chloride synthesis by HCl/C2H2 mixed gas and ethyne hydrochlorination for enriching or separating recovering of the HCl. The adsorption rate of the HCl is up to 99.97%, and thepurity of HCl thus obtained is high, up to 99.999%.

The utility model relates to a refining method of by-product HCl gas in organic chlorine production process, the by-product HCl gas passes by the absorption post filled with absorption resin at flow speed of 0.1-0.5m/s under constant-temperature constant-pressure, the removal ratio of the organic in the HCl gas can reach 99.8 percent, afterwards the absorption resin that absorbs the organic is desorbed by 110-160 DEG C saturation vapor, the desorption ratio can exceed more than 99 percent, the desorption liquid is condensed, oil-gas separated, recycled to obtain the organic mixture containing benzene or chlorobezene, the mixture is furthermore distilled and separated to obtain the benzene or chlorobezene, finally the absorption resin after desorbed by the vapor is dried by 110-140 DEG C hot air, and then cooled to room temperature for next stage absorption. The absorption resin can be reused after desorption and regeneration.

The invention provides an electronic grade hydrogen chloride purification method. The method is characterized by comprising the following steps: introducing industrial liquid hydrogen chloride with purity of 99% to the middle position of a first rectifying tower to be rectified so as to remove light components; introducing a liquid coming out from the bottom of a reboiler of the first rectifying tower to the middle position of a second rectifying tower by a pump to be rectified, condensing hydrogen chloride generated through heating by a second reboiler with a second condenser, controlling the reflux ratio, enabling part of hydrogen chloride to flow back to the second rectifying tower and transferring the other part of hydrogen chloride to middle storage tanks to be stored and pumping out residual liquid from the bottom of the second reboiler to a waste liquid storage tank so as to remove heavy components; and obtaining high-purity hydrogen chloride with purity above 99.9999% through adsorption and purification of at least an adsorption tower with a molecular sieve inside. The method has the effect of avoiding introduction of other impurity media, is simple to operate and is low in production cost.

The invention discloses a green and environment-friendly recycling method of trichlorosilane tail gas, which comprises the following steps: (1) transmitting the tail gas generated in the process of synthesizing trichlorosilane to an absorption tower, adopting two-stage absorption by an absorption tower, cooling hydrogen exhausted from the tower top of the absorption tower to obtain a liquid phase component, reflowing the liquid phase component to the top of the absorption tower, conducting heat exchange for coarse chlorosilane and hydrogen chloride exhausted from the tower bottom of the absorption tower, and transmitting chlorosilane condensate to a rectifying tower for rectification with the coarse chlorosilane and the hydrogen chloride after heat exchange; (2) completely reflowing overhead fraction in the rectifying tower after passing through the condensed liquid phase, and simultaneously entering into a cryogenic device in a gaseous phase mode for condensation, extracting hydrogen chloride in a liquid phase mode, and returning the gaseous phase mixture extracted from the cryogenic device to the absorption tower as feeds; and (3) enabling one part of tower bottom discharged material to enter into coarse chlorosilane rectification system and the other part thereof after cooling to return the absorption tower as a main absorption liquid in step (1). The invention adopts a recycling system which comprises a single tower for two-stage absorption and rectification so as to obtain hydrogen, hydrogen chloride and chlorosilane with high purity and completely eliminate tail gas emission.

The invention relates to a device and method for preparing hydrogen chloride gas through continuous method full hydrochloric acid analysis. The device comprises an analysis system and a dilute sulfuric acid vacuum concentration system, wherein the analysis system comprises a hydrochloric acid analysis tower, a first-stage hydrogen chloride cooler, a second-stage hydrogen chloride cooler, a concentrated sulfuric acid drying tower and an acid mist separator; the dilute sulfuric acid vacuum concentration system comprises a dilute sulfuric acid flash tank, an acid-acid heat exchanger, a first-stage sulfuric acid concentration tank, a second-stage sulfuric acid concentration tank, a first-stage washing tower, a first-stage water vapor condenser, a second-stage washing tower, a second-stage water vapor condenser, a wastewater storage tank and a concentrated sulfuric acid intermediate tank. According to the device, high-concentration sulfuric acid serves as an extraction agent, and dilute heat of concentrated sulfuric acid is fully utilized; meanwhile, the concentrated sulfuric acid is continuously added from the top of the hydrochloric acid analysis tower so that the reflux ratio of thetop of the hydrochloric acid analysis tower can be reduced to the minimum, and the energy consumption is reduced to the maximum extent; a segmented vacuum concentration technology is adopted, and waste heat of later-stage acid is fully utilized, so that the heating steam consumption is reduced to the maximum extent, and technical support is provided for long-period continuous work of the device.

The invention relates to a method for refining a chlorine hydride byproduct and recovering trifluoromethane in production of monochlorodifluoromethane. Refined high-purity chlorine hydride can directly serve as a raw material for synthesizing vinyl chloride monomers; and the trifluoromethane byproduct separated in the refining process can be effectively recovered, wherein the refining of the HCl comprises the following steps of: crude separation, absorption, analysis, condensation, capture of acid mist, and adsorption; and after a F23 byproduct in the production of the monochlorodifluoromethane is separated in the absorption process in the refining of the HCl, the F23 byproduct is subjected to lossless compression and rectification to form the trifluoromethane with the purity of over 99 vol percent. By combining the recovery and comprehensive utilization of the HCl and the recovery of the trifluoromethane, the high consumption of water resources and liquid caustic soda is avoided, and the production cost of the monochlorodifluoromethane is reduced; and the effective recovery of the trifluoromethane prevents environmental pollution, and the chloroalkali, the monochlorodifluoromethane and polyvinyl chloride (PVC) can be circularly produced.

The method includes following steps, (A) adsorption: to filter industrial by-product hydrochoric acid containing organic substances (benzene, methylbenene, chlorobenzene and triclene etc.) from tens to hundreds, the organic substance in the by-product hydrochoric acid is absorbed on resin by adsorption tower filled with phenylethene and styrene-divinglbenzene large aperture adsorbing resin, the by-product hydrochoric acid being absorbed is colourless and transparent, the content of organic substance can be reduced below 1 mg/L. (B) deadsorption; to do deadsorption and regeneration to the larger aperture adsorbing resin which absorbed organic substances during step A that water vapour is used as absorbent agent, the deadsorption temp. is 110-150 deg.C, the time is 2-16 hrs, (C) recovery: to recover the organic substances by gas and liquid deadsorption, oil and water sepaation, the water phase is returned to hydrogen chloride adsorption process to be used generating by-product hydrochloric acid.

The invention relates to a method for purifying a byproduct hydrogen chloride in fluorinated alkane production. The method comprises the following steps: sequentially passing the byproduct in fluorinated alkane production through a first absorption tower filled with an activated carbon absorbent, a second absorption tower filled with an aluminum oxide absorbent, and a third absorption tower filled with a molecular sieve absorbent and a silica gel absorbent, so as to obtain a hydrogen chloride product, wherein the weight content of the hydrogen chloride in the hydrogen chloride product is less than 5 ppm, the weight content of an organic fluoride is less than 50 ppm, and the weight content of water is less than 50 ppm. The purified hydrogen chloride gas can be used for synthesizing products such as vinyl chloride monomers, metal chloride, chlorocarbon and trichlorosilane, and raw materials for preparing chlorine in a oxychlorination mode, the application range of the byproduct hydrogen chloride gas is widened, the additional value is improved, and compared with the conventional process that the hydrogen chloride gas is converted into a byproduct hydrochloric acid, the method has remarkable economic benefits.

A process for the co-production of gaseous HCl and a salt product comprising a cation and an anion, which process comprises the steps of a. providing an aqueous solution comprising protons, chloride anions, and cations and anions of the salt product, b. bringing the solution into contact with a substantially immiscible extractant, the extractant comprising: 1) an oil soluble amine, which amine is substantially water insoluble both in free and in salt form; and 2) a carrier solvent for the amine; whereupon HCl selectively transfers to the extractant to form an HCl-carrying extractant and a chloride depleted aqueous solution containing the salt product; c. separating the HCl-carrying extractant from the chloride-depleted aqueous solution; and d. distilling HCl from the separated HCl-carrying extractant to form gaseous HCl and HCl depleted extractant.