385 results about "Sulfite salt" patented technology

The invention provides a preparation method of 4-fluoro-3, 5-dimethylphenylhydrazine hydrochloride, which comprises the following steps: salifying 4-fluoro-3, 5-dimethylaniline serving as a substrate with concentrated hydrochloric acid, reacting with sodium nitrite to prepare a diazo solution, reducing the diazo solution into corresponding phenylhydrazine by using alkaline sodium sulfite as a reducing agent system, and reacting the 4-fluoro-3, 5-dimethylphenylhydrazine hydrochloride with the diazo solution to prepare the 4-fluoro-3, 5-dimethylphenylhydrazine hydrochloride. And acidizing the 2, 5-dimethyl phenylhydrazine to obtain corresponding phenylhydrazine hydrochloride. According to the preparation method, sodium sulfite which is low in cost and easy to obtain is used as a reducing agent, the defects that metal residues are high, the environment is prone to being polluted and the raw material cost is high due to the fact that a metal reducing agent is adopted when phenylhydrazine hydrochloride is prepared in the prior art are overcome, the reaction is completed in a water phase, no organic solvent is adopted, and the concept of green chemistry is met; and the problems of complicated post-treatment and easy pollution caused by the adoption of an organic solvent can be effectively avoided.

The invention discloses a yellow reduction dyeing agent, a dyeing solution and a preparation method and application thereof, and relates to the technical field of dyeing and finishing. According to the yellow reduction dyeing agent provided by the invention, the 5-hydroxy-3-aminopyridine-2, 6-(1H, 3H)-diketone is adopted as a reduction dye, and the sodium sulfite is independently used as a reducing agent for reduction dyeing, so that the obtained dye leuco body is proper in dyeing capacity, and a dyed fabric can show excellent light brittle damage resistance. The fabric dyed by the dyeing agent has similar breaking strength before and after dyeing and even is slightly improved after dyeing and illumination, meanwhile, the color depth K / S of the fabric dyed by the dyeing agent reaches 3.2 or above, the dry and wet rubbing color fastness can reach level 4 or above, and the color fastness to illumination reaches level 6 or above.

The invention provides high-performance silver powder suitable for TOPCon battery fine grid silver paste, a preparation method of the high-performance silver powder and the silver paste, and belongs to the technical field of photovoltaic materials. The preparation method comprises the steps that a silver salt solution and a composite reducing agent are mixed, a first-stage hydrothermal reaction is carried out at the first temperature, a second-stage hydrothermal reaction is carried out at the second temperature, and silver powder is obtained after centrifugation, washing and drying; wherein the composite reducing agent is selected from a mixture of two of potassium tartrate, sodium sulfite and ferrous sulfate. According to the method, gradual growth and crystallinity improvement of silver crystal nucleuses are achieved through two-stage heating, particle aggregation or uneven morphology caused by rapid reduction is avoided, in addition, the adopted composite reducing agent combination is remarkably superior to a single reducing agent (such as ascorbic acid), and the morphology and particle size distribution of the silver powder can be more accurately regulated and controlled.

The invention relates to an indole hair dye based on air oxidation. The hair dye provided by the invention is characterized in that a chemical strong oxidant is not added, and oxygen in air can be catalyzed by using an air oxidation catalyst and a metal ion catalyst to naturally finish the oxidative polymerization process of indole substances (natural bionic melanin precursor substances). The used reducing agent is a combination of cysteine and a derivative thereof and sodium sulfite and a derivative thereof, the oxidative polymerization speed of indole substances can be controlled, and finally generated melanin macromolecules are embedded in hair cortex, so that white hair is obviously blackened. The natural oxidation process does not need hydrogen peroxide, destructive strong base or organic base, so that the use of harmful chemical reagents is reduced, the formula is simplified, the hair dyeing process is milder, potential hazards to hair and scalp are reduced, and the natural oxidation hair dye is safe, environmentally friendly and sustainable.

The invention discloses a filtering aid method for improving the filtering efficiency of monazite superior soluble slag, which comprises the following steps: step 1, carrying out solid-liquid separation on mixed slurry after alkali cake superior soluble callback to obtain filter residue 1 and filtrate 1; step 2, adding water into the filter residue 1, mixing and stirring according to a liquid-solid ratio of (1-2.5): 1 to react for 0.5-4 hours, and carrying out solid-liquid separation on ore pulp after the reaction to obtain a filter residue 2 and a filtrate 2; 3, if the ore pulp filtering speed in the step 2 is lower than 20 L / (m < 2 > * h) or the water content of obtained filter residues 2 is larger than 60%, the step 2 is repeated for the filter residues 2, the composite reducing agent with the preset mass is added, and stirring reaction is conducted for 2 hours till the water content of the filter residues is smaller than or equal to 60% or the ore pulp filtering speed in the plate and frame filtering process is larger than or equal to 20 L / (m < 2 > * h); in the step 3, the mass ratio of the added composite reducing agent to the original dry slag is (5-50) kg: 1t, and the composite reducing agent comprises sodium sulfite and thiourea in the mass ratio of (1-2): 1. The invention aims at shortening and improving the slag filtering performance so as to shorten the filtering time.

The invention relates to the technical field of water treatment agents, and particularly discloses an anti-corrosion deoxidizing composite agent for geothermal well recharge water and a preparation method of the anti-corrosion deoxidizing composite agent. The invention relates to an anti-corrosion and deoxidizing composite agent for geothermal well recharge water. The anti-corrosion and deoxidizing composite agent comprises the following raw materials: 30-40 parts of double modified sodium sulfite, 10-20 parts of a corrosion inhibitor, 8-15 parts of a scale inhibitor, 5-10 parts of amino trimethylene phosphonic acid, 5-10 parts of etidronic acid, 3-8 parts of polyethylene glycol monomethyl ether acrylate and 40-50 parts of deionized water. The dual-modified sodium sulfite is obtained by sequentially modifying sodium sulfite with a silane coupling agent and acrylic acid. The corrosion-resistant and oxygen-removing composite agent has the advantage of being high in oxygen-removing efficiency stability, the corrosion-resistant and scale-inhibiting functions are synchronously and synergistically improved on the basis that the oxygen-removing efficiency stability is guaranteed, and the complex working condition requirements of geothermal well recharge are completely met.

The present invention belongs to the technical field of fabric color fixing agents and provides a novel acidic color fixing agent free of bisphenol S and a preparation method thereof; the acidic color fixing agent is composed of the following components in parts by weight: 15-25 parts of water, 10-15 parts of phenol, 15-25 parts of dimethylacetamide, 2-5 parts of sodium sulfite, 10-15 parts of acetic acid, 5-7 parts of concentrated sulfuric acid, 15-20 parts of acrylic acid, 2-5 parts of ethylene glycol dimethyl ether, and 1-3 parts of sorbitol; the preparation method comprises the following steps: mixing a formula amount of phenol, dimethylacetamide, acrylic acid, acetic acid, and sodium sulfite, heating, adding concentrated sulfuric acid to react, cooling, adding a formula amount of water, and adding a formula amount of ethylene glycol dimethyl ether and sorbitol to obtain the product. Compared with the prior art, the present invention does not contain bisphenol S, has a good color fixing effect, can effectively improve various fastnesses such as water fastness, perspiration fastness, and seawater resistance, has little effect on the color change of the fabric after treatment, and has good tolerance to hardness ions.

Methods and systems of PFAS destruction in water containing nitrate. The methods and systems include filtering water containing PFAS and nitrate through a membrane selective for PFAS to obtain a membrane reject containing PFAS and nitrate and a filtrate containing nitrate, forming a treatment solution using the membrane reject including diluting the membrane reject and combining the membrane reject with a photosensitizer, a sulfite salt, and a sufficient amount of base such that the treatment solution has a pH of about 10 or more, and irradiating the treatment solution with UV light in a photoreactor to destroy a portion of the PFAS. Before dilution, a concentration of PFAS in the membrane reject may be between about 3 times and about 20 times greater than before the filtering step. Dilution of the membrane reject may include between about a 3 and about a 20 times dilution.

The invention relates to a method for recycling lead by treating lead plaster of a waste lead-acid storage battery, and belongs to the technical field of lead secondary resource recycling. The method comprises the following steps: (1) slurrying lead paste with water to obtain slurry; adding sodium carbonate and sodium sulfite into the slurry, heating and then carrying out reduction-conversion reaction under a certain temperature condition to obtain a reaction mixture containing a lead-containing solid and a liquid phase; (2) carrying out solid-liquid separation on the reaction mixture obtained in the step (1) under the condition that the temperature is not lower than 40 DEG C to obtain a lead-containing solid; (3) drying the lead-containing solid obtained in the step (2) to obtain a dried lead-containing material; and (4) the dried lead-containing material obtained in the step (3) is subjected to high-temperature reduction smelting, and metal lead is obtained. According to the method, a wet process and a pyrogenic process are adopted, the used raw materials such as sodium carbonate, sodium sulfite and pea coal are cheap and easy to obtain, the whole technological process is short, operation is easy, the lead recovery rate is high, and industrial large-scale application and popularization are facilitated.

The invention discloses a method for enriching valuable elements by collaborative smelting of magnesium slag and desulfurized gold concentrate, which comprises the following steps: uniformly mixing desulfurized gold concentrate, magnesium slag and solvent powder, granulating and drying to obtain mixed granules; the mixed granules are added into a reduction furnace, a reducing agent is added for reduction smelting, and slag and precious iron alloy are obtained; the method comprises the following steps: crushing the precious iron alloy, and leaching to obtain leaching residues and a leaching solution 1; acid is added into the leaching residues for gold dissolving, leaching liquid 2 is obtained, then sodium sulfite is added into the leaching liquid 2, and gold powder is obtained; adding hydrochloric acid into the leachate 1 to obtain a silver chloride solid and a leachate 3; and heating and pressurizing the leachate 3, and adjusting the pH value to obtain the hematite-form precipitate. According to the method, calcium oxide, silicon oxide and magnesium oxide in the magnesium slag serve as slag formers for reduction smelting of the desulfurized gold concentrate in the high-temperature process, iron alloy is obtained through synergistic reduction smelting, meanwhile, valuable elements such as gold, silver and copper in raw materials are captured, the gold recovery rate is increased to 98% or above under the cyanidation-free condition, the silver recovery rate is increased to 95%, and the iron recovery rate reaches 92%.

The invention provides a salinized soil curing agent and an in-situ curing method of salinized soil, and belongs to the field of industrial solid waste resource utilization and road engineering. The salinized soil curing agent comprises solid waste dry powder and a meta-aluminate enhancer, the solid waste dry powder comprises 20-25 parts by mass of fly ash, 30-35 parts by mass of superfine slag powder, 25-35 parts by mass of superfine steel slag powder and 10-25 parts by mass of desulfurized gypsum; the mass of the meta-aluminate enhancer is 1%-5% of the mass of the solid waste dry powder; the salinized soil is sulfate salinized soil or sulfite salinized soil. According to the salinized soil curing agent, sulfate or sulfite in salinized soil can be directly used as an exciting agent, salt stabilization and soil body structure strengthening are synchronously achieved, meanwhile, industrial solid waste can be effectively utilized, use of traditional high-energy-consumption cementing materials is avoided, construction energy consumption is reduced, and the environmental protection pressure of road construction is relieved.

The application provides a method for synthesizing an eplerenone intermediate N-1 by one-pot method, and belongs to the technical field of organic synthesis. The method is characterized in that: the eplerenone intermediate N-4 is dissolved in dichloromethane, a potassium carbonate aqueous solution and dibromohydantoin are added to perform an opening ring reaction; after the reaction is completed, hydrochloric acid is directly added to perform a rearrangement reaction; then water is separated and methanol is added in the organic layer to perform an ozonation reaction; then sodium sulfite is added to perform a reduction reaction; then hydrochloric acid is added to perform a methyl esterification reaction, so as to obtain the eplerenone intermediate N-1 crude product, and finally the eplerenone intermediate N-1 fine product is obtained through refining. The method realizes the one-pot synthesis of the eplerenone intermediate N-1 from the eplerenone intermediate N-4 through the continuous reactions of opening ring, rearrangement, ozonation, reduction and methyl esterification, and can avoid column chromatography purification, so that the method becomes a green chemical process route with greatly reduced organic solvent consumption and wastewater.

The invention belongs to the technical field of desulfurization environmental protection, and particularly relates to a process method for extracting a sodium sulfite product through sodium desulfurization post-treatment and a dust removal device. Comprising the following steps: absorbing saturated desulfurization mother liquor in a desulfurization device, conveying the saturated desulfurization mother liquor into a desulfurization mother liquor tank by a slurry discharge pump, adding a sodium hydroxide solution with a certain concentration into the desulfurization mother liquor tank, and reacting and crystallizing to separate out a certain amount of sodium sulfite crystals; conveying the slurry in which a certain amount of crystals are separated out into a cyclone separator through a desulfurization mother liquor pump, and carrying out solid-liquid pre-separation in the cyclone separator; according to the invention, industrial waste gas generated after extraction of sodium sulfite can be reused, and pollution is reduced; the filtering membrane adsorbing sodium sulfite can be thoroughly cleaned; the unextracted sodium sulfite mixed in the dried and separated waste gas can be fully extracted and recovered, so that the extraction rate is increased; and stacking and packaging are carried out while the sodium sulfite is recycled, so that the collecting and packaging efficiency is improved.

The invention relates to the technical field of industrial wastewater treatment, in particular to a treatment method for treating high-sulfonic-group wastewater by advanced oxidation, which comprises the following steps: regulating the pH value of the wastewater to 3.0-4.0, then carrying out photo-Fenton oxidation, controlling the molar ratio of H2O2 to Fe < 2 + > to be 300: 1-400: 1, regulating the pH value of the effluent to 5.0-6.0, adding sodium sulfite to quench residual H2O2 and flocculate and precipitate iron mud, and finally, carrying out secondary oxidation on the wastewater to obtain the high-sulfonic-group wastewater. Performing anaerobic-aerobic biochemical treatment on the supernate, adding sodium carbonate and sodium hydroxide into biochemical effluent to soften and descale, concentrating in a mechanical vapor recompression evaporator, washing and recrystallizing crystallized mother liquor, and adsorbing and purifying the crystallized mother liquor with activated carbon to obtain an industrial salt product. The problem of MVR evaporation scaling is effectively solved by accurately controlling the neutralization pH and combining the softening step, finally, wastewater standard treatment and salt high-quality recovery are achieved, the COD removal rate can reach 95% or above, and excellent environmental and economic benefits are achieved.

This invention discloses an acetic acid-modified inorganic composite gel material and its preparation method, belonging to the field of organic material synthesis technology. The acetic acid-modified inorganic composite gel material comprises the following materials in parts by weight: 0.2-0.4 parts of acetic acid-Co3O4, 1.5-2.5 parts of acrylamide, 1-1.5 parts of glycerol, 0.05-0.1 parts of N-N-dimethylformamide, 0.25-0.5 parts of ammonium persulfate, 0.1-0.15 parts of sulfonated-Bi2O3, 0.6-0.9 parts of ethylenediamine, and 0.2-0.4 parts of PVP; the acetic acid-Co3O4 comprises materials in the following mass ratio: acetic acid:cobalt nitrate:thiourea:ammonium fluoride:sodium bicarbonate = 3-7:1.5-2.5:0.8-1.2:0.5-1:6; the sulfonated-Bi2O3 comprises materials in the following mass ratio: Bi2O3:sodium sulfite:H2O2:ammonium bicarbonate = 3-5:0.2-0.6:1-1.5:1. This material achieves efficient and stable catalysis for nitrogen reduction under mild conditions through structural defect regulation, interfacial functional group modification, heterojunction electronic regulation, and synergistic enhancement with organic gel.

The invention discloses a cyclosporine detection kit and application thereof, the cyclosporine detection kit comprises a reagent R1 comprising a magnetic bead coated cyclosporine antibody and a Tris buffer solution I, a reagent R2 comprising an alkaline phosphatase labeled cyclosporine antigen and an AP stabilizer, a reagent R3 comprising an MES buffer solution, and a reagent R4 comprising an MES buffer solution. The sample treating agent comprises a Tris buffer solution III containing copper sulfate pentahydrate, sodium sulfite, a preservative, methanol and ethylene glycol. According to the cyclosporin detection kit and the application thereof, the R1, R2 and R3 reagents are combined and applied to the to-be-detected sample treated by the specific Tris buffer solution I sample treating agent, the specific detection of cyclosporin is improved through the synergistic effect of the specific Tris buffer solution I, the AP stabilizer and the specific MES buffer solution, the detection accuracy and stability are good, the repeatability is good, and the kit is suitable for large-scale popularization and application. The problems of cross reaction and insufficient stability during detection of a to-be-detected sample are solved.

The application discloses a preparation method of a pesticide lignosulfonate sodium dispersant composition and belongs to the technical field of dispersants. The method comprises the following steps: S1, taking papermaking black liquor as raw material, performing standing precipitation, flocculation precipitation, membrane concentration and acid precipitation treatment to obtain purified lignin; S2, adding the purified lignin into water, adjusting the pH of the system to 10-11, then adding hydrogen peroxide to perform pre-oxidation, then adding formaldehyde and sodium sulfite to perform sulfomethylation reaction, and adding formaldehyde to perform polycondensation reaction; cooling and discharging, and performing spray drying to obtain lignosulfonate sodium; and S3, adding the lignosulfonate sodium and 1-ethyl-3-methyl imidazolium L-lactate into water and stirring and uniformly mixing, adding stevioside to perform ultrasonic treatment, forming a homogeneous system, and performing spray drying to obtain the pesticide lignosulfonate sodium dispersant composition. The lignosulfonate sodium dispersant composition can effectively improve the pesticide dispersion stability and pesticide biological activity, and meets the pesticide use requirement.

The application discloses a feed oil and meat and bone meal co-production preparation process for improving protein retention rate, and relates to the field of animal feed.The preparation process comprises the following steps: S1, after crushing livestock and poultry slaughter by-products, water, lactic acid and sodium sulfite are added, and stirring treatment is conducted to obtain pretreated materials; S2, composite strain seed liquid is inoculated into the pretreated materials, and fermentation is conducted; S3, the fermented materials are heated, enzyme inactivation and sterilization treatment are conducted, and three-phase centrifugal separation is conducted to obtain upper oil, middle layer fermentation protein liquid and lower layer very fine bone residue; S4, the upper oil is subjected to water washing and vacuum dewatering to obtain feed oil; and the middle layer fermentation protein liquid and the lower layer very fine bone residue are combined and then subjected to low-temperature vacuum drying to obtain meat and bone meal.The process can effectively improve protein digestibility and protein retention rate, does not need high-temperature and high-pressure treatment, effectively retains heat-sensitive amino acids, and the product is rich in small-molecule peptides and soluble calcium and has excellent quality.

The invention discloses an inhibitor-free high-efficiency flotation process for a lead-zinc-sulfur preferential flotation whole process, which cancels the addition of an inhibitor in the lead-zinc-sulfur flotation whole process, adopts overflow water of a zinc concentrate thickener to replace a zinc inhibitor, and comprises the following steps: (a) lead flotation operation: adopting the overflow water of the zinc concentrate thickener to inhibit zinc minerals, a collecting agent with high selectivity is added for flotation of lead minerals; (b) zinc flotation operation: adding an activating agent and a collecting agent with higher selectivity into lead flotation tailings for flotation of zinc minerals, wherein a sulfur inhibitor is not added; and (c) sulfur flotation operation: adding a collecting agent into the zinc flotation tailings for flotation of sulfur minerals, not adding an inhibitor and an activating agent, not adjusting the pH value, not adjusting the concentration and not desliming. According to the method, an inhibitor (lime / zinc sulfate / sodium sulfite) is eliminated in the whole process, a strong-selectivity collecting agent is adopted, inhibition on associated gold and silver in the lead-zinc mineral is relieved, the silver recovery rate is increased to be larger than or equal to 69.55% from 51%, the silver content of the lead concentrate is increased to be larger than or equal to 1733.77 g / t from 1500 g / t, and the gold and silver recovery rate is synchronously increased by 10% or above.

The present application provides a kind of hair care composition containing potassium iodide and its preparation method, the hair care composition includes A agent and B agent;The A agent includes 5,6-dihydroxyindole, potassium iodide, arginine, propylene glycol, sodium sulfite, ascorbic acid, xanthan gum and water;The B agent includes sodium laureth sulfate, potassium peroxodisulfate, cocamidopropyl betaine, disodium lauroyl glutamate, decyl glucoside, cocamide MEA, guar hydroxypropyltrimonium chloride, sodium chloride, citric acid, disodium EDTA, essence and water.The present application improves the stability of 5,6-dihydroxyindole by using potassium iodide mixed with 5,6-dihydroxyindole, improves the problem that dyeing effect is not obvious, uneven, dyeing is not persistent, and there is no risk of damage to hair and scalp by strong alkaline substances, avoids using benzidine substances with high carcinogenic and sensitizing risk, and the hair dyeing effect is more persistent, more mild, and safer.

The invention relates to a synthesis method of sulfopropionic anhydride. The synthesis method comprises the following steps: (1) mixing 3-bromopropionic acid and sodium sulfite in water, and carrying out sulfonation reaction to obtain a mixture; (2) mixing the mixture with an acidifying agent, and carrying out acidification reaction to obtain 3-sulfonyl propionic acid; and (3) mixing the 3-sulfonyl propionic acid with a dehydrating agent and an organic solvent, and carrying out a dehydration reaction to obtain the sulfopropionic anhydride. According to the invention, compounds such as 3-bromopropionic acid and sodium sulfite are used as reaction raw materials to prepare sulfopropionic anhydride. The method has the advantages of cheap and easily available raw materials, simple operation and high yield, and is suitable for large-scale production.

The application relates to an ultrasonic treatment method of high-impurity copper anode slime. The ultrasonic treatment method is realized through hierarchical ultrasonic strengthening and synergistic leaching. In the first-stage leaching, hydrogen peroxide-oxygen-rich air composite oxidants are combined with ultrasonic cavitation effects to realize efficient oxidation leaching of arsenic, antimony and bismuth; in the second-stage leaching, sulfuric acid-sodium sulfite mixed leaching agents are used to remove harmful impurities such as arsenic, antimony and bismuth under ultrasonic strengthening, and to efficiently enrich valuable metals such as gold, silver, selenium and tellurium, so that the treatment period is shortened, energy consumption and reagent consumption are reduced, resource comprehensive utilization is improved, and the method is suitable for efficient separation and resource recovery of high-impurity copper anode slime containing refractory impurities such as arsenic, antimony and bismuth and valuable metals such as gold, silver, selenium and tellurium.

This invention discloses an apparatus and process for removing sulfur dioxide from flue gas using siderite slurry, relating to the field of environmental protection technology. The apparatus comprises six major components: desulfurization, slurry circulation, slurry replenishment, oxidation, defoaming emission, and spent slurry treatment. The components are interconnected by pipelines. The process includes siderite pretreatment slurry preparation, slurry replenishment, flue gas desulfurization, sulfite oxidation, flue gas defoaming emission, and spent slurry treatment. Siderite is crushed and ground into a slurry with a specific particle size and solids content, which is then contacted countercurrently with sulfur-containing flue gas. Utilizing ferric carbonate, magnesium carbonate, and calcium carbonate in the slurry as desulfurizing agents, combined with the oxidation effect of air and ferric ions, sulfur dioxide is converted into ferric sulfate and calcium sulfate, achieving desulfurization. This invention has high desulfurization efficiency, with the sulfur dioxide content in the purified flue gas below 50 mg / Nm³. 3 It makes full use of low-grade siderite resources, and the desulfurization by-products can be utilized as resources. The process is simple and has no secondary pollution, resulting in significant economic and environmental benefits.

A method for the resource utilization of chromium-containing sludge involves conditioning, decomposition, and roasting of the sludge. During roasting, a non-oxidizing atmosphere is introduced for protection, ensuring that chromium (Cr) is enriched in the residue in a non-toxic, non-volatile, low-valence state, thus producing high-value-added calcium-chromium sand. Simultaneously, sulfur-containing flue gas is collected during roasting to produce sulfuric acid or sodium sulfite, preventing sulfur diffusion and air pollution. This significantly reduces hazardous solid waste emissions from related production processes and lowers hazardous waste disposal costs. This method achieves both the harmless treatment of chromium-containing sludge and the comprehensive resource utilization of chromium, calcium, and sulfur within the sludge.

The invention relates to the technical field of vanadium batteries, and provides a vanadium battery electrolyte and a preparation method thereof.The preparation method comprises the steps that vanadium pentoxide, concentrated sulfuric acid and water are mixed and then heated, then acid ester is added, then boiling, cooling and filtering are conducted in sequence, and the vanadium battery electrolyte is obtained; the mass ratio of vanadium pentoxide to concentrated sulfuric acid is 1: (1.3-1.5); the mass ratio of the vanadium pentoxide to the acid ester is 1: (1.1-1.3); the acid ester comprises the following components in percentage by mass: 50-51% of oxalic acid, 4-5% of sodium sulfite and 45-46% of ethyl acetate. Compared with the traditional vanadium battery electrolyte, the use amount of the concentrated sulfuric acid and oxalic acid is greatly reduced, the obtained electrolyte is weakly acidic, the corrosivity and danger are greatly reduced, and the electrolyte is not easy to separate out and not easy to block a film in the charging and discharging process. In conclusion, compared with the traditional electrolyte, the vanadium battery electrolyte provided by the invention is safer, more environment-friendly and more efficient.

The present application relates to the field of natural gas decarburization, and discloses a decarburization solvent, a decarburization method and system of carbon-containing natural gas, the decarburization solvent comprising a main agent, an activator and an auxiliary agent; wherein the main agent is N-methyldiethanolamine, the activator comprises a primary amine and a secondary amine, and the auxiliary agent is selected from at least one of potassium sorbate, sodium sorbate and sodium sulfite.The decarburization solvent and the decarburization method provided by the present application can not only make the absorption and regeneration equipment flexible to follow the change of the CO2 content of the raw gas in the natural gas development process and expand, but also avoid the corrosion and foaming of the tower equipment in the conventional process; meanwhile, the absorption and regeneration performance of the decarburization solution can be improved under the condition of meeting the purification index, and the regeneration heat consumption and the power consumption for pressurization of the amine liquid circulation can be greatly reduced.

The application relates to the field of calcium dobesilate preparation, and particularly discloses a preparation method of calcium dobesilate, which comprises the following steps: a. adding anhydrous sodium sulfite into water to dissolve, so as to form an anhydrous sodium sulfite aqueous solution; b. screening and refining mannitol, and then stirring and mixing the mannitol with the anhydrous sodium sulfite aqueous solution obtained in the step a, so as to form a mixture; c. drying the mixture obtained in the step b to less than 1% of moisture, and then granulating, so as to obtain mannitol particles; d. uniformly mixing a certain amount of calcium dobesilate, the mannitol particles and a sodium citrate lubricant, so as to obtain mixed granules; and e. tabletting the mixed granules obtained in the step d. The application has the beneficial effect of providing the preparation method of the calcium dobesilate which can improve the quality of the calcium dobesilate.

The invention provides a waste lithium ion battery negative electrode copper foil recovery method, which comprises: crushing a negative electrode material to a particle size of less than or equal to 5 mm, carrying out room temperature pretreatment with 1-5% dilute sulfuric acid for 0.5-2 h, and separating to obtain a pretreated copper foil; then hydrogen peroxide or glucose is used as a reducing agent, reduction acid leaching is carried out under the conditions of specific concentration sulfuric acid, temperature, time and solid-to-liquid ratio, and copper-containing filtrate and carbon-containing filter residues are separated out; and immersing the copper foil into a sodium sulfite (0.4-0.6 M)-hydrochloric acid (pH = 2.0-3.0) solution containing the auxiliary agent, carrying out magnetic field stirring reaction at room temperature for 4-6 hours, filtering, and adding iron powder to reduce copper ions, so that efficient recovery of the copper foil and deep removal of impurities are realized, and the process is environment-friendly and efficient.

The invention belongs to the technical field of hydrochloric acid recovery, and discloses a benzene chlorination process byproduct hydrochloric acid impurity removal refining system and method.The method comprises the steps that sodium sulfite is added into hydrochloric acid to remove free chlorine, organic matter in hydrochloric acid is adsorbed through polystyrene-based macroporous resin, iron ions are adsorbed through amino-containing ion exchange resin, and the hydrochloric acid is recycled; hydrochloric acid is fed into a desorption tower for heating desorption, obtained pure hydrogen chloride gas is fed into an absorption tower for secondary absorption, and absorbed water is ultrapure water. According to the method, a combined process of resin adsorption and hydrogen chloride desorption and reabsorption is adopted, volatile impurities are firstly removed, then non-volatile inorganic impurities are deeply adsorbed, the labor division is clear, the efficiency is high, the final product is clear and transparent, the quality is stable, the economic benefit is remarkable, low-value and difficult-to-treat waste acid is converted into high-value commodity hydrochloric acid, waste is turned into wealth, and the method is suitable for industrial production. And remarkable economic benefits are created, and the environmental protection pressure is reduced.

Described herein are methods and systems for increasing the injectivity of wells used to inject water or water containing various chemicals such as water-soluble polymers for the purpose of increasing the recovery of hydrocarbons such as crude oil from a hydrocarbon-bearing formation. Injectivity often decreases because of adverse reactions or plugging at or near the wellbore. The treatment procedure involves injecting reducing agents (e.g., sulfite or metabisulfite salts) dissolved in water or water containing other chemicals such as polymers.