Patents
Literature
Patsnap Copilot is an intelligent assistant for R&D personnel, combined with Patent DNA, to facilitate innovative research.
Patsnap Copilot

55results about "Sulfite preparation" patented technology

Method for treating tail gas of acyl chlorination

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.
Owner:JIANGSU YANGNONG CHEM +2

Method for treating tail gas of thionyl chloride chlorination

The invention discloses a method for treating tail gas generated in chlorination reaction by using thionyl chloride. The existing traditional tail gas treatment method is costly due to a large amount of alkali consumption, and the pressure on environmental protection is high due to the final generation of a large amount of waste water containing heteroions. In the present invention, by controlling the amount of water, the hydrogen chloride in the tail gas is subjected to two-stage absorption with water, and the concentrated hydrochloric acid with a hydrogen chloride content close to saturation and a small amount of sulfur dioxide is obtained through the first-stage absorption; the second-stage absorption: after the first-stage absorption, the The exhaust gas is subjected to the second-stage absorption, and the added water is not discharged to obtain dilute hydrochloric acid containing a small amount of hydrogen chloride and a small amount of sulfur dioxide. The dilute hydrochloric acid is used as the raw material water for the first-stage absorption; after the above-mentioned secondary absorption treatment, it is then treated with alkali or alkali The third level of water absorption is used to absorb sulfur dioxide in the tail gas to obtain a relatively pure aqueous solution of sodium sulfite. The invention has high treatment efficiency, complete tail gas absorption, and reduces the pressure on environmental protection.
Owner:GAOYOU CITY ORGANIC CHEM FACOTRY

Process for production of ammonium thiosulphate

A process for continuous production of ammonium thiosulphate, (NH4)2S2O3 (ATS) from NH3, H2S and SO2 comprising steps of: (a) partial condensation in a partial condenser 4 of a first gaseous or partial liquid feed stream comprising H2O, H2S and NH3 with a molar H2S:NH3 ratio <0.4; (b) passing the aqueous condensate comprising NH4HS and NH3 from the partial condenser 4 to a reactor 9 in which said condensate is contacted with a third feed gas stream 7 comprising H2S and with an aqueous solution 10 comprising NH4HSO3 and (NH4)2SO3 under formation of an aqueous solution of (NH4) 2S2O3; (c) passing the gas stream comprising NH3 and H2S from the partial condenser 4 to a mixing device 13 in which said gas stream is completely dissolved in the water drained off from the aerosol filter 25; (d) passing a second feed gas stream 20 comprising approximately 2/3 mole SO2 per mole of NH3 contained in the first feed stream to a SO2 absorber 21 and the aerosol filter 25; (e) passing the aqueous solution produced in mixing device 13 to the SO2 absorber 21; (f) passing the off gas from the absorber 21 to the aerosol filter 25 and (g) adding to the aerosol filter 25 a balance amount of water required for obtaining approximately 40-65 wt % (NH4)2S2O3 in the aqueous of solution of (NH4)2S2O3 being withdrawn from the reactor 9.
Owner:HALDOR TOPSOE AS

Fume purification system with tower box

The invention provides a fume purification system with a tower box, belonging to the technical field of fume treatment and environmental equipment. According to the fume purification system, absorbing boxes are longitudinally arranged so as to form a tower box structure; a gas resolving space separated from a fume passage is constructed; an alkaline absorbant is used for absorbing SO2 and NOx in fume in the absorbing box; according to the theory that the alkaline absorbent dynamically absorbs and resolves NOx, then the resolved NOx is conveyed to an NOx recovery system so as to be recovered, products generated by liquid phases in the absorbing boxes absorbing SO2 are mainly sulfites which are directly discharged out from an absorbing system, and a larger usable space is left. The fume purification system has the beneficial effects (1) the absorbing tanks are longitudinally combined to form a tower box structure, so that convenience in combination is achieved; (2) absorbing slurry pumps are applicable to liquid-phase pumps, and the liquid phase flows smoothly; (3) the fume and absorbing slurry in the absorbing box at each level are in cross-flow contact, but an overall countercurrent contact structure is formed; (4) the desulfurization rate is greater than or equal to 99%, the denitration rate is greater than or equal to 90%, the NOx recovery rate is greater than or equal to 90%, and the pure value of byproducts is high.
Owner:JIANGSU TANDGE ENVIRONMENTAL ENG

Method for using sulphur gas for reducing waste sulfuric acid to prepare liquid sulfur dioxide and sulfuric acid

The invention relates to a method for using sulphur gas for reducing waste sulfuric acid to prepare liquid sulfur dioxide and sulfuric acid. Sulphur is gasified into the high-temperature sulphur gas,the raw material waste sulfuric acid is washed, evaporated, concentrated and split into gas, the two streams of gas is reacted in a reduction furnace to make sulfur trioxide in the waste sulfuric acidsplit gas reacted with the gas sulphur to generate sulfur dioxide gas, organic matters, powdered carbon and the like in the waste sulfuric acid split gas generate sulfur dioxide, carbon dioxide, carbon monoxide, nitrogen, hydrogen chloride, water and the like, reduced furnace gas is subjected to complete combustion, waste heat recovery, purification and drying to obtain sulfur dioxide gas, part of the sulfur dioxide is liquefied to prepare a high-purity liquid sulfur dioxide product, and sulfur dioxide-containing gas which is not liquefied and the other part of the sulfur dioxide gas are mixed, and are subjected to conversion and absorption to prepare the concentrated sulfuric acid. Compared with the prior art, the method has the advantages that low temperature is used for conducting purification, concentration and regeneration resource utilization on the waste sulfuric acid to prepare high-quality liquid sulfur dioxide and concentrated sulfuric acid products, meanwhile, impurities ofthe organic matters, salt and the like in the waste sulfuric acid are subjected to proper harmless treatment, no secondary pollutants are generated, and resource recycling and environmental friendliness are achieved.
Owner:上海三夫工程技术有限公司

Method used for desulphurization and denitration closed cycle and sulfur resource recovery

The invention provides a method used for desulphurization closed cycle and denitration and sulfur resource recovery. The method comprises the following steps: 1, dedusting; 2, desulphurization and denitration; and 3, sulfur resource recovery. The problems of difficult treatment and secondary pollution of byproducts, high running cost and product singleness in the prior art are effectively solved through the method. Desorption, reduction and regeneration of desulphurization byproducts are fully utilized according to market demands. The purpose of the method is to treat wastes with wastes and kill many birds with one stone, circulate and recovery wasted sulfur resources in coal-fired flue gas with lowest cost, improve the comprehensive added values of the desulphurization byproducts and reduce the running cost, so the method has the advantages of realization of long-term and high-efficiency running and self-sufficiency closed cycle of dedusting, desulphurization and denitration, resource saving, energy saving, consumption reduction, no wastewater discharge, no secondary pollution, resource recovery and environment treatment requirement meeting, and increase of the economic and social benefits of enterprises.
Owner:天津佳晟染料贸易有限公司

Method for treating tail gas of thionyl chloride chlorination

The present invention discloses a disposal method of a tail gas, which is produced from a thionyl chloride used in a chlorination reaction. The cost of the prior traditional tail gas disposal method is high because of large consumption of alkali, and a high environmental protection pressure is resulted from a plurality of finally produced waste water which contains heteroions. Firstly, the present invention uses water to absorb the hydrogenchloride of the tail gas by controlling the water consumption, and a first grade absorption obtains a concentrated hydrochloric acid, the a hydrogenchloride content of which is approximately saturated and little sulfur dioxide is contained; a second grade absorption is that water is used to process the tail gas after the first grad absorption for the second grade absorption, which is that the added water is not discharged to obtain a diluted hydrochloric acid which contains little hydrogenchloride and little sulfur dioxide, and the diluted hydrochloric acid is used as a liquid of raw material used for the first grade absorption; then the alkali or alkaline water is used to process the tail gas after the second grade absorption for a third grade absorption to absorb the sulfur dioxide in the tail gas and obtain a quite pure sodium sulfite aqueous solution. The disposal efficiency of the present invention is high, and the tail gas absorption is complete, which reduces the environmental protection pressure.
Owner:GAOYOU CITY ORGANIC CHEM FACOTRY
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products