57 results about "Sodium hydrosulfide" patented technology

The invention provides a preparation method of a magnetic recoverable catalyst and a method for synthesizing 3-mercaptopropionic acid, and mainly solves the problem that a large amount of acid and alkali solutions are needed in the existing acrylonitrile-sodium hydrosulfide and acrylic acid-thiourea process routes. The thiohydracrylic acid synthesis catalyst is prepared. The use conditions of the catalyst are as follows: the temperature is 30-80 DEG C, the reaction pressure is 0.5-3 MPa, the mass ratio of the acrylic acid to the solvent is 0.1-5, and the mass ratio of the acrylic acid to the catalyst is 0.2-20. Compared with the prior art, the catalyst disclosed by the invention is used as a synthetic catalyst for preparing thiohydracrylic acid through reaction of acrylic acid and hydrogen sulfide, a solid catalyst and a liquid reaction system can be completely separated by adopting simple methods such as filtration, centrifugation or magnetic separation, and a complicated pickling step is not needed; and the problem that a homogeneous catalyst is difficult to rectify after salification in the use process is avoided.

The utility model relates to the technical field of chemical engineering, in particular to a sodium hydrogen sulfide solution storage tank flushing system which comprises a magnetic turning plate liquid level meter, a remote transmission liquid level meter, a sodium hydrogen sulfide storage tank, a condensation water pipeline, an upper flushing line, a lower flushing line and a remote transmission flushing line. A lower end inlet of the magnetic flap liquid level meter is connected with a lower end drain valve; a first short-circuit wire is led out from the sodium hydrosulfide storage tank to be connected to an outlet in the upper end of the magnetic flap liquid level meter, a second short-circuit wire is led out from the sodium hydrosulfide storage tank to be connected to an outlet in the lower end of the magnetic flap liquid level meter, a third short-circuit wire is led out from the sodium hydrosulfide storage tank to be connected to the remote transmission liquid level meter, and a remote transmission shower valve is arranged on the third short-circuit wire. On-line flushing of the sodium hydrogen sulfide solution storage tank is achieved, when liquid level display is different from remote liquid level, water flushing is carried out, checking is carried out again after flushing, and the operation risk is reduced.

The invention relates to the technical field of chemical material preparation, and particularly discloses a safe preparation method of a short fluorocarbon alkyl sulphobetaine surfactant, a product and application, and the safe preparation method comprises the following steps: (1) in a solvent system I, reacting epoxy chloropropane with secondary amine to obtain an intermediate 1; (2) in a solvent system II, reacting the intermediate 1 with sodium hydrosulfide or a hydrate thereof to obtain an intermediate 2; (3) reacting the intermediate 2 with short fluorocarbon alkyl iodide to obtain perfluoroalkyl thioether propyl tertiary amine; and (4) carrying out sulfonation treatment on perfluoroalkyl thioether propyl tertiary amine to obtain the short-fluorocarbon alkyl sulphobetaine surfactant. According to the invention, by designing a synthetic route without using a high-risk reagent, the safety and operability of the process are remarkably improved, and the sulphobetaine surfactant with excellent acid, alkali and salt chemical stability and excellent surface activity is successfully prepared; and a key material and a safe and reliable preparation process are provided for development of a new-generation efficient environment-friendly fire extinguishing agent.

The invention provides a method for removing chemical oxygen demand by using a catalyst prepared from acid mine wastewater, which comprises the following steps: recovering valuable elements in the acid mine wastewater, accurately adding sodium hydrosulfide to control conditions, recovering transition metal elements with catalytic activity in the acid mine wastewater by fractional precipitation, directionally preparing a nano-scale metal catalyst, and removing the chemical oxygen demand by using the catalyst prepared from the acid mine wastewater. And the chemical oxygen demand in the wastewater is degraded through the prepared nano-scale metal catalyst, so that the problem of environmental pollution caused by the mine wastewater and the wastewater containing the chemical oxygen demand is solved, and the dual effects of resource recovery and environmental treatment are realized.

The application discloses a kind of complex antimony-containing material high-efficiency antimony leaching method, solve the problem of low efficiency of antimony leaching and difficult solid-liquid separation when using conventional sodium sulfide alkali method to leach antimony.By alkali leaching and arsenic removal, copper and bismuth removal by chlorine salt reduction and acid leaching, and NaHS+NaOH combined antimony leaching after treatment, high-efficiency leaching and enrichment of antimony in complex antimony-containing material is realized.Compared with the leaching effect of sodium sulfide, the leaching efficiency of antimony is significantly improved, and the leaching rate of antimony in the process of NaHS+NaOH combined antimony leaching is stable at more than 96%.Compared with sodium sulfide, sodium hydrosulfide has the advantages of low price, low sodium content, low temperature and difficult crystallization, etc., so using sodium hydrosulfide instead of sodium sulfide to leach antimony can effectively reduce production cost, reduce sodium content in high-salinity wastewater from the source, and avoid the disadvantages of using liquid sodium sulfide storage tank, conveying pipeline, etc.

The invention relates to a polycarboxylic acid water reducer and a preparation method thereof, and belongs to the technical field of polycarboxylic acid water reducers. The polycarboxylic acid water reducer comprises the following components: isopentenyl polyoxyethylene ether, acrylic acid, an acrylate monomer, modified talcum powder, sodium lignin sulfonate, sodium gluconate, ethylene glycol monovinyl polyethylene glycol ether, ammonium persulfate, methyl ethyl ketone peroxide, sodium hydrosulfide, a chain transfer agent and deionized water. The prepared water reducing agent has excellent fluidity, dispersibility and mechanical strength after being added into concrete.

The utility model relates to a calcium carbonate solid waste treatment device, and discloses a treatment device for calcium carbonate solid waste generated by sodium hydrosulfide purification, which comprises a box body, a plurality of spray heads and two crushing rollers, a filter assembly is arranged in the box body, and the two crushing rollers are arranged in the filter assembly and are rotatably connected with the inner wall of the box body; a driving assembly for driving the annular screen to rotate is arranged in the box body, a water conveying assembly is arranged in the box body, the multiple nozzles are arranged on the water conveying assembly, a blocking assembly for blocking nozzles of the multiple nozzles is arranged on the water conveying assembly, and a feeding pipe for conveying materials into the filtering assembly is arranged in front of the box body. The plane of the inclined panel makes contact with the nozzles of the multiple sprayers, due to the elastic force of the two springs, the plane of the inclined panel blocks the nozzles of the multiple sprayers all the time, and powder generated when calcium carbonate solid waste is broken is prevented from entering the nozzles of the sprayers, blocking of the nozzles is avoided, and damage to the nozzles is avoided.

The utility model relates to a kind of multi-stirring efficient vulcanization reaction kettle, including tank body, mixer and gas pipe, the liquid outlet of the mixer is connected with the side of tank body intercommunication;The side of tank body away from mixer is equipped with liquid outlet;Tank body bottom is equipped with slag outlet;Slag outlet is equipped with slag valve;The gas pipe is set in tank body top, and one end of gas pipe is inserted into tank body, and the other end is connected with gas conveying device.The utility model can mix waste acid and vulcanizing agent fully by mixer;And hydrogen sulfide gas is delivered to tank waste acid by gas pipe, so that hydrogen sulfide gas and waste acid react, conveniently recycle hydrogen sulfide gas, reduce the consumption of sodium hydrosulfide and sodium hydroxide, reduce processing cost.

The high-precision purification equipment comprises a distillation box and a condensation pipe, the lower end of the inner surface of the distillation box is movably connected with a second connecting shaft, the outer surface of the second connecting shaft is fixedly connected with stirring blades, and the right end of the top of the distillation box is fixedly connected with a sleeve; the left front end of the sleeve is communicated with the top of the distillation box through a one-way pipe. According to the sodium hydrosulfide distillation device, a sodium hydrosulfide solution is fed into the distillation box from the feed port, the heating plate is opened, the sodium hydrosulfide solution can be heated, steam generated by heating enters the front end of the inner cavity of the sleeve through the one-way pipe, enters the condensation pipe through the pipeline and finally enters the collection box through the pipeline, and in the process, the steam can enter the distillation box through the pipeline. The steam can blow the fan blades to rotate, the fan blades can drive the first connecting shaft to rotate when rotating, and the fan blades can drive the second connecting shaft to rotate under the cooperation of the single-face tooth synchronous belt, so that the stirring blades are used for stirring the sodium hydrosulfide solution, and the purification efficiency is effectively improved.

The invention belongs to the technical field of organic compounds, and particularly relates to a preparation method of 3-octanoyl thiopropyl triethoxy silane. The preparation method of 3-octanoyl thiopropyltriethoxysilane provided by the invention comprises the following steps: dissolving a sodium hydrosulfide solid and a sodium hydroxide solid in water under a protective atmosphere, adding a first phase transfer catalyst, and then dropwise adding capryloyl chloride for a first substitution reaction to obtain an intermediate; adding a second phase transfer catalyst into a system after the first substitution reaction, dropwise adding chloropropyltriethoxysilane to carry out a second substitution reaction, and carrying out post-treatment to obtain 3-octanoyl thiopropyltriethoxysilane; the post-treatment comprises the following steps: cooling a system after the second substitution reaction, separating liquid, and taking an organic phase; and washing the organic phase with water, and sequentially performing dehydration and distillation low boiling. The preparation method disclosed by the invention is simple and easy to operate, and the prepared 3-octanoyl thiopropyltriethoxysilane has relatively high purity and yield.

The invention discloses a method for comprehensively enriching and recovering cadmium and thallium from complex arsenic sulfide slag, belongs to the technical field of harmless treatment of dangerous waste residues and resource recovery of rare and noble metals, and aims to solve the problems that the existing process is difficult to realize fractional separation of fluorine, chlorine, arsenic, cadmium and thallium in the arsenic sulfide slag, and the thallium is low in recovery rate and insufficient in purity. According to the method, fluorine and chlorine and thallium arsenic-cadmium lead are separated through graded alkaline leaching; the cadmium-containing lead slag is subjected to zinc electrodeposition waste liquid acid leaching and sodium sulfite and citric acid purification, and cadmium-containing coarse filtrate is obtained; adjusting the pH value of the thallium-containing arsenic liquid step by step, and adding sodium hydrosulfide for precipitation to obtain high-purity thallium slag; according to the method, no toxic gas is generated, the emission of wastewater is reduced by 80%, conventional equipment is used, industrialization is easy, and unification of harmlessness of hazardous waste and efficient recycling of resources is achieved.

The utility model relates to the technical field of chemical production, in particular to a pipeline system for preventing blockage of sediment at the bottom of a sodium hydrosulfide tank. The sodium hydrosulfide tank connector is arranged at the bottom of the sodium hydrosulfide tank body, and the sodium hydrosulfide tank connector is provided with a first port located in the tank and a second port located outside the tank; the Y-shaped loading pipeline comprises a connecting pipe, a first suction pipeline and a second suction pipeline which are distributed in a Y shape, the connecting pipe is connected with the first port, a plurality of first suction holes are formed in the first suction pipeline in the length direction, and a plurality of second suction holes are formed in the second suction pipeline in the length direction; the Y-shaped loading pipeline is horizontally arranged in the sodium hydrosulfide tank body; an inlet of the external loading pipeline is connected with the second port, an outlet of the external loading pipeline is connected with a loading connector of a transport vehicle, and a loading pump is arranged on the external loading pipeline. The problems that the sodium hydrosulfide storage tank is difficult to load and cannot be loaded are effectively solved, and meanwhile, the tank cleaning period of the sodium hydrosulfide storage tank is prolonged.

The utility model discloses a two-stage evaporation and concentration device for a sodium hydrosulfide-containing solution, which comprises an intermediate tank provided with a buffer inlet, a buffer outlet, a heat preservation steam inlet and a heat preservation liquid outlet; the two evaporation and concentration assemblies are respectively arranged on the feeding side and the discharging side of the intermediate tank, and each evaporation and concentration assembly comprises a feeding pump; the heating concentration unit comprises a heater, a separator and a circulating pump; a discharge pump; a live steam treatment unit; and a secondary steam treatment unit. According to the two-stage evaporation and concentration device for the sodium hydrosulfide-containing solution, the two evaporation and concentration assemblies are adopted for sequentially carrying out evaporation and concentration, the separation effect is improved, the operation conditions can be flexibly adjusted to meet the requirements of products with different concentrations, the equipment load can be shared together, the service life is prolonged, the maintenance cost is reduced, and equipment operation is more stable and reliable; the requirement of the device on the corrosion resistance of materials is reduced, and the intermediate tank avoids the situation that the fluidity is reduced due to material cooling through heat preservation.

The invention provides mercaptopropyl long-chain silane and a synthesis method and application thereof, and belongs to the technical field of chemical synthesis, and the synthesis method comprises the following steps: carrying out substitution reaction on chloropropyltriethoxysilane and fatty alcohol-polyoxyethylene ether, and then adding sodium hydrosulfide for reaction to obtain mercaptopropyl long-chain silane. The obtained mercaptopropyl long-chain silane can better improve the dispersity of white carbon black in a rubber material, the rubber material is better in wear resistance and lower in rolling resistance, and meanwhile mercaptopropyl long-chain silane is soluble in water and higher in environmental protection property.

The invention provides a synthesis method of mercaptopropyltrimethoxysilane, which comprises the following steps: dissolving industrial sodium hydrosulfide in a composite solvent, separating water through azeotropic distillation, reacting the separated and dewatered industrial sodium hydrosulfide-composite solvent solution with chloropropyltrimethoxysilane to obtain a reaction product, and carrying out heat preservation on the reaction product; carrying out cooling, filter pressing, rectification and separation on the reaction product subjected to heat preservation to obtain mercaptopropyltrimethoxysilane; the composite solvent comprises a first type of solvent and a second type of solvent, the first type of solvent is a non-water-soluble solvent, and the second type of solvent is a water-soluble solvent. According to the method, after water in sodium hydrosulfide is removed through azeotropic distillation, chloropropyltrimethoxysilane is added for full reaction, so that reaction products are prevented from being reacted with water, and after the reaction is completed, high-purity mercaptopropyltrimethoxysilane is obtained through cooling, filter pressing and distillation separation.

The application relates to a preparation method and application of a 2-acyl benzothiazole compound, which comprises the following steps: placing sulfur ylide in a sealed tube, adding a solvent to dissolve, and obtaining a first reaction system; adding nitrosobenzene into the first reaction system, stirring at a certain temperature for a certain time, and obtaining a second reaction system; adding sodium hydrosulfide, dimethyl sulfoxide, a metal salt, potassium persulfate and an alkali into the second reaction system, heating and stirring in the sealed tube to react, and obtaining a third reaction system; and carrying out post-treatment on the third reaction system to obtain the 2-acyl benzothiazole compound.The application has the advantages that the reaction condition is mild, the price of the sodium hydrosulfide sulfur source is low, and the reaction yield is high; the substrate applicability range is wide, various substrate structures can tolerate the reaction condition, and the 2-acyl benzothiazole derivative with diversified structures can be rapidly prepared.

The invention provides a postharvest normal-temperature logistics quality maintaining method for Wushan crisp plum fruits and application of the postharvest normal-temperature logistics quality maintaining method, and belongs to the technical field of fruit preservation. According to the method, the Wushan crisp plums are soaked in the sodium hydrosulfide, so that the preservation of the Wushan crisp plums is realized. The sodium hydrosulfide treatment can delay the reduction of color change and hardness of the picked Wushan crisp plums, delay the increase of respiration rate and ethylene generation rate of the picked Wushan crisp plums and the reduction of titratable acid content, inhibit the softening and rotting of the picked green crisp plums, prolong the shelf life, and improve the quality of the green crisp plums. The safe storage period of the fruits under the normal-temperature storage condition is prolonged by more than 3 days. Therefore, as an exogenous treatment substance which is simple to operate, safe and effective, sodium hydrosulfide has a certain application prospect in the field of preservation and fresh-keeping of the picked Wushan crisp plums.

This invention belongs to the field of fine chemical technology, specifically relating to a method for preparing sodium hydrosulfide using acidic gas. The invention constructs a multi-stage co-current absorption system with progressively decreasing total alkalinity concentration. The product outlet is located at the stage with the lowest total alkalinity, utilizing a low-alkalinity medium to suppress CO2 absorption, reducing the generation of sodium carbonate impurities by more than 67% at the source. Combined with room-temperature chemical precipitation for decarbonization and staged cooling crystallization for impurity removal, the system systematically solves the problem of difficult removal of soluble impurity salts such as CO2, NH3, and sodium thiosulfate. This invention uses industrial sulfur-containing tail gas as raw material, fully utilizing the exothermic reaction between H2S and NaOH to maintain the absorption temperature. Vacuum evaporation utilizes the residual heat from condensation for staged replenishment, achieving efficient sulfur resource recovery and green production. The process is simple, the equipment is mature, and the production line can switch between producing 43% liquid sodium hydrosulfide or over 70% solid sodium hydrosulfide, flexibly adapting to tail gas with different H2S concentrations.

The application discloses an adsorbing material for efficiently removing mercury and a preparation method thereof. The preparation method comprises the following steps: cutting cellulose, and washing the cellulose in anhydrous ethanol by ultrasonic to remove impurities, and obtaining defatted cellulose after vacuum drying; adding the defatted cellulose into an organic solution containing bromoacetyl bromide, stirring and reacting at 25-60 DEG C for 24-72 h, then filtering, washing with anhydrous ethanol, and drying to obtain brominated cellulose; under the protection of nitrogen, adding the brominated cellulose and sodium hydrosulfide into anhydrous ethanol, stirring and reacting at 60-90 DEG C for 24-96 h, then filtering, washing with water or ethanol, and drying to obtain the adsorbing material. The application has low cost, can effectively improve the density and dispersity of mercapto functional groups in the adsorbing material, can efficiently and quickly remove mercury in various media, and the prepared adsorbing material has good stability and selectivity.

The utility model relates to the technical field of biogas desulfurization, and discloses an integrated alkali wash desulfurization device which comprises a circulating tank body, and further comprises a spray tower body and a packed tower body which are arranged in the circulating tank body, and a gas-water separator body is arranged on the right side of the packed tower body; the water supplementing pipe and the alkali supplementing pipe are communicated with the interior of the circulating tank body; the liquid discharging assembly is arranged on one side of the circulating tank body; the first purification assembly is arranged in the spray tower body; the second purification assembly is arranged in the packed tower body; by controlling the pH value of absorption liquid in the circulating tank, hydrogen sulfide in the biogas is quickly converted into sodium hydrosulfide so as to be removed from the biogas, the primary spray tower, the secondary packed tower and the gas-water separator are integrated in the circulating tank, the circulating tank and the circulating pump are arranged on the same base, and the circulating pump is arranged on the circulating tank. Due to the compact design, the occupied area of equipment is greatly reduced, and the engineering construction period is shortened.

Compositions and methods for the separation and recovery of one or more minerals from a mineral ore bulk material are provided. The compositions and methods include selectively depressing minerals utilizing an ammoniated polycarbamide as a separation aid. The ammoniated polycarbamide reduces, or eliminates, the conventional use of depressants such as sodium hydrosulfide (NaSH) in mining flotation processes, including copper-molybdenum (Cu-Mo) separations.

The present application relates to the field of mineral flotation reagent, in particular to application of a combined inhibitor in flotation separation of copper-molybdenum mixed concentrate. The present application first adds sodium sulfide / sodium hydrosulfide to the copper-molybdenum mixed concentrate for removing reagent; then adds the combined inhibitor to inhibit chalcopyrite; further adds collector and frother to obtain molybdenum rough concentrate and copper rough concentrate through roughing; the molybdenum rough concentrate is refined to obtain molybdenum concentrate, and the copper rough concentrate is scavenged to obtain copper concentrate. The combined inhibitor is composed of oxalyl dihydrazide and mercaptobenzoic acid organic matter, and the total amount of oxalyl dihydrazide and mercaptobenzoic acid organic matter in roughing is 0.5-8 kg / t of copper-molybdenum mixed concentrate. The present application can effectively improve the separation efficiency of copper-molybdenum flotation, reduce the amount of inhibitor, and has the advantages of green and efficient, clean and environmentally friendly, strong applicability, etc., and can realize efficient separation of copper-molybdenum mixed concentrate.

The invention relates to the technical field of sodium hydrosulfide processing, and particularly discloses sodium hydrosulfide concentration and purification equipment and a production process, the sodium hydrosulfide concentration and purification equipment comprises an evaporation tank, and an auxiliary mechanism and a driving mechanism are arranged in the evaporation tank; the auxiliary mechanism comprises an auxiliary frame which slides up and down and is rotationally assembled in the evaporation tank, and an extrusion assembly which is connected with the driving mechanism and internally stores a part of solution; the auxiliary frame comprises a connecting part and an isolating part, and the isolating part and the inner wall of the evaporation tank are arranged at intervals and define an evaporation cavity; after being started, the driving mechanism drives the isolation part to synchronously move up and down and rotate through the extrusion assembly; when the isolation part moves downwards, the solution in the extrusion assembly is discharged and enters the evaporation cavity through the lower portion of the isolation part, and when the isolation part moves upwards, the solution in the evaporation cavity flows back into the extrusion assembly. The sodium hydrosulfide concentration and purification equipment and the production process have the effect that the concentration procedure can be stably carried out.

The application discloses a kind of molybdenum bis (dibutyl dithiocarbamate) oxide and preparation method thereof, comprising the following steps: molybdenum trioxide, phase transfer catalyst and water are uniformly mixed, are sent into first-stage mixing reactor, sodium hydrosulfide, sodium thiosulfate and water are uniformly mixed, also are sent into first-stage mixing reactor, and first reaction solution is obtained by reaction;Di-n-butylamine and water are uniformly mixed, are sent into second-stage mixing reactor, carbon disulfide is simultaneously sent, and second reaction solution is obtained by reaction;First reaction solution, second reaction solution are respectively sent into third-stage mixing reactor and are reacted, obtain molybdenum bis (dibutyl dithiocarbamate) oxide solution, solid-liquid separation, drying, obtained immediately.The yield of product obtained by the application is high, the purity is high, the quality is stable, the whole reaction process is continuously carried out in airtight container, there is no gas volatilization, which is conducive to environmental protection, reaction solvent is water, resource consumption is less, can be recycled, clean and environmentally friendly.

This invention relates to the field of electronic materials technology, and discloses a spherical shell copper sulfide powder material and its preparation process. The preparation process includes: mixing copper hydroxide with additives and grinding, followed by multi-stage temperature calcination to obtain copper oxide; dispersing copper oxide in water, adding a sulfur source solution to react and generate copper sulfide; and obtaining the spherical shell copper sulfide powder material through solid-liquid separation, washing, drying, and granulation. The additives are sodium sulfate or sodium chloride, added at 3%–10% of the mass of copper hydroxide; the sulfur source is sodium sulfide or sodium hydrosulfide, with a copper-sulfur molar ratio of 1:1 to 1:2; calcination is performed in multiple temperature zones below 200℃, 200–300℃, 300–400℃, and 450–500℃, followed by annealing; the solid content of copper oxide in the reaction is ≤20%, the concentration of the sulfur source is ≤20%, and the stirring speed is controlled in stages. This process is mild, uses safe raw materials, and has a simplified procedure. The obtained powder material has a hollow spherical shell structure and can be used to prepare infrared interference or shielding materials.

The invention discloses low-end-group chlorine polyphenylene sulfide and a preparation method thereof.The preparation method comprises the following steps that N-methyl pyrrolidone, a sodium hydrosulfide aqueous solution, a hydroxide aqueous solution and a catalyst are mixed, and a mixture is obtained; removing free water in the mixture, adding N-methyl pyrrolidone and p-dichlorobenzene into the mixture under a nitrogen protection atmosphere, heating to 180-240 DEG C, carrying out an early polymerization reaction, heating to 240-270 DEG C, adding a third monomer, and carrying out a later polymerization reaction; and after the reaction is finished, cooling, filtering, washing and drying to obtain the low-end-group chlorine polyphenylene sulfide. Through an innovative synthesis process, the prepared PPS resin with low end group chlorine is uniform in particle shape, the product yield is in an industry leading level, and the problems that in a traditional process, the content of end group chlorine of a product is high, and the product gradually dissociates in the processing process are effectively solved; by means of excellent performance, the packaging film can be widely applied to high-end fields such as electronic component packaging and the like.

The utility model discloses a concentration and purification device for a byproduct sodium hydrosulfide solution and belongs to the technical field of waste liquid treatment equipment. The preheating assembly, the first-stage evaporation and concentration assembly, the second-stage evaporation and concentration assembly and the condensation assembly are sequentially connected, a discharging opening in the bottom of the first-stage evaporation and concentration assembly is communicated with a feeding opening of the first-stage evaporation and concentration assembly, and a discharging opening in the bottom of the second-stage evaporation and concentration assembly is communicated with a feeding opening of the second-stage evaporation and concentration assembly; a gas outlet in the top of the first-stage evaporation and concentration assembly, a gas outlet in the top of the second-stage evaporation and concentration assembly and a gas outlet in the top of the first-stage condensation assembly are all communicated with the hydrogen sulfide absorption assembly. According to the device, the concentration of sodium hydrosulfide in the filtration liquid can be improved, most impurities can be removed, so that the sodium carbonate and other impurities in the product are few, the decomposition of sodium hydrosulfide is little, the product yield is high, and continuous automatic production is realized; and pollution to the environment is avoided.

This invention discloses an enzymatic hair removal device and method for reducing hydrogen sulfide at the source. It aims to use a biological enzyme bath as the hair removal solution to avoid the malodorous smell of hydrogen sulfide and sulfide pollution in wastewater caused by traditional depilatory agents such as sodium sulfide or sodium hydrosulfide. The device includes a housing, a rotating drum, and a comb plate. The housing has a storage chamber and a hair discharge port on the front. The rotating drum is located within the storage chamber, with hair discharge grooves on its circumference, radially protruding protrusions on its inner side, and comb teeth on its outer circumference. The comb plate is inclined within the drum, with one side contacting the circumference of the drum and the other side extending from the hair discharge port to the outside of the housing. The side of the comb plate in contact with the drum has comb grooves corresponding to the comb teeth. During the hair removal process, the rotating drum and the comb plate work together to promptly collect and discharge shed animal hair, preventing it from tangling and forming balls, reducing the amount of hair retained in the storage chamber, and mitigating the problems of reduced enzyme concentration and decreased hair removal efficiency caused by hair adsorbing the hair removal solution.

The invention belongs to the field of high polymer material synthesis, and particularly provides a preparation method of an antioxidant PPS melt-blown material.In the polymerization process, a naphthalene ring structure monomer is introduced to be subjected to condensation polymerization with p-dichlorobenzene and sodium hydrosulfide in a polar solvent, a PPS copolymer containing a naphthalene ring structure is formed, the oxidation resistance of the PPS copolymer can be improved through introduction of a naphthalene ring, and the antioxidant performance of the PPS melt-blown material is improved; the strength and the toughness of the material can also be enhanced; when the composite material is applied to preparation of the melt-blown material, the subsequent modification treatment of coating, dipping or adding an antioxidant on the surface of the melt-blown material can be reduced, the process is simplified, the production efficiency is improved, and the production cost of the melt-blown material is reduced.

The invention provides a preparation method of mercaptoacetic acid. The preparation method comprises the following steps: esterification reaction: reacting chloroacetic acid with methanol to generate methyl chloroacetate; a sodium hydrosulfide aqueous solution is added into methyl chloroacetate, a quaternary ammonium salt phase transfer catalyst is added at the same time, and a methyl thioglycolate sodium salt aqueous solution is generated through a reaction; acidizing and hydrolyzing: dropwise adding hydrochloric acid into the sodium methyl thioglycolate aqueous solution to adjust the pH value, heating and hydrolyzing to obtain a crude thioglycolic acid product; extracting and concentrating to obtain a thioglycolic acid extraction concentrated solution; and rectification and purification: adding an organic thiol reducing agent and a phenothiazine stabilizing agent into the thioglycollic acid extraction concentrated solution, and carrying out vacuum rectification to obtain thioglycollic acid. According to the method, hydrolysis by-products are inhibited through esterification pre-protection, an organic thiol-phenothiazine synergistic system stabilizes sulfydryl activity, and the problems of low purity, more impurities and poor stability in the prior art are solved.