52 results about "Sodium dithionite" patented technology

The invention relates to the technical field of nicotinic acid synthesis, and particularly discloses an efficient nicotinic acid synthesis method based on step-by-step feeding dynamic control, which comprises the following specific steps: step 1, uniformly dividing potassium permanganate into 3 parts, adding the potassium permanganate into an aqueous solution containing 3-methylpyridine every 15 + / -5 minutes, and supplementing 5-8mL of water after each addition; 2, reacting at 70-90 DEG C for 2-4 hours, and filtering while the solution is hot; 3, adding sodium dithionite into the filtrate, wherein the mass of the sodium dithionite is 0.4-0.6 time that of the potassium permanganate; and 4, concentrating the filtrate to 30-50% of the original volume, adjusting the pH value to 3.0-3.5 with acid, and crystallizing to obtain the nicotinic acid. The method has the following effects: the yield is up to 89.52% at most; the cost is reduced: the consumption of hydrochloric acid is reduced by 77%, and the consumption of potassium permanganate is optimized by 16.7%; the efficiency is improved; the reaction time is shortened by 50%; the large fluctuation of the reaction temperature is controlled through step-by-step feeding, the problem that the reaction liquid which is not completely reacted is too alkaline is solved by filtering and adding sodium dithionite, and the false yield is eliminated through the purification and concentration step while the yield is further improved.

The invention discloses a high-yield method for reducing dinitro and retaining sensitive protecting groups, which comprises the following steps: adding water, sodium dithionite and sodium carbonate into a container, stirring and clarifying, and dropwise adding a mixed solution containing raw materials; after the reaction is finished, extracting, separating liquid, concentrating, and purifying by silica gel column chromatography to obtain a product and a byproduct; the raw material is a compound containing a carbon-carbon double bond, a p-methoxybenzyl protecting group, a t-butyloxycarboryl protecting group and dinitro. Adding a byproduct into a phosphoric acid mixed solution for reaction; and after the reaction is finished, adding dichloromethane and water, dropwise adding triethylamine to adjust the pH value, extracting, separating liquid, drying, concentrating, and purifying by silica gel column chromatography to obtain the product. According to the method, a sodium hydrosulfite / sodium carbonate system and phosphoric acid step-by-step treatment strategy is adopted, reduction of dinitro is achieved under mild conditions, meanwhile, PMB protecting groups, Boc protecting groups and C-C double bonds are reserved, and the problem that stability and high yield of the protecting groups cannot be considered at the same time in an existing method is solved.

This invention belongs to the field of epoxy resin synthesis technology, specifically relating to epoxy resin and an anhydrous epoxy resin synthesis process. The anhydrous epoxy resin synthesis process of this invention includes the following steps: dissolving bisphenol A in an organic solvent, adding sodium dithionite and mixing thoroughly, then adding solid sodium hydroxide, reacting under negative pressure and heating conditions, filtering after the reaction, adding the sodium bisphenol A solution to epichlorohydrin containing solid sodium hydroxide, and heating to carry out the resin synthesis reaction; after the reaction, performing solid-liquid separation, collecting the liquid phase and performing vacuum distillation to remove the solvent and unreacted epichlorohydrin, obtaining the epoxy resin. The anhydrous epoxy resin synthesis process provided by this invention avoids epichlorohydrin hydrolysis and is a novel epoxy resin synthesis process that is low-cost, highly efficient, and ensures excellent product color. The epoxy resin prepared by this invention guarantees product quality, with low color and low epoxy equivalent.

The present invention relates to the technical field of dispersants, and discloses a polymer-based dispersant and a preparation process and application. The present invention reacts polyethylene glycol and 5-nitroisophthalic acid to obtain a dispersant precursor; then reduces the nitro group through sodium dithionite to obtain a polymer-based dispersant, which contains polyethylene glycol molecular chains, has good complexing and stabilizing effects on silver ions, plays the role of a dispersant, is conducive to suppressing the agglomeration of nano silver, and reduces particle size. The polymer-based dispersant contains a terminal hydroxyl reducing group of polyethylene glycol, and the molecular chain side chain contains a large amount of reducing aniline groups, which plays the role of a reducing agent. It can effectively achieve the reduction of silver ions at low temperatures, significantly improving the output of nano silver.

This invention belongs to the field of soil manganese extraction technology, and discloses a stepwise extraction method and application for manganese species in soil. First, exchangeable manganese is extracted using magnesium chloride; then, manganese carbonate and sulfides are extracted using hydrochloric acid; next, active Mn(III) bound to organic matter is extracted using pyrophosphate solution under alkaline pH; then, manganese oxides are dissolved using hydroxylamine hydrochloride; and finally, manganese bound to crystalline iron and manganese oxides is extracted using sodium dithionite solution. This stepwise extraction scheme accurately quantifies the concentration of active Mn(III) species bound to organic matter in the soil. Experimental results show that the extraction method of this invention can effectively separate different forms of manganese in soil. In particular, PP extraction successfully distinguishes Mn(III) bound to organic matter without introducing interfering substances such as iron minerals that may interfere with dissolution.

The present application relates to the technical field of mineral processing and metallurgy, and particularly relates to a processing technology for full combustion of sulfur ore in a fluidized bed furnace, which comprises the following steps: after the pyrite is crushed, the pyrite is screened and then compounded, and then the pyrite is floated with a high-efficiency inhibitor to obtain pretreated pyrite powder; the pretreated pyrite powder is then added into the fluidized bed furnace, is leveled and then is fully combusted to obtain furnace gas and furnace slag; the high-efficiency inhibitor is obtained by mixing sodium hyposulfite, sodium mercaptoacetate, sodium humate and a buffer; wherein the furnace temperature during the full combustion is 910-930 DEG C, the combustion duration is 4-5 h, and the oxygen concentration at the outlet of the fluidized bed furnace is 2.5%-3.0%. The specific particle size and high-quality combination roasting process of the pretreated pyrite powder make the present application have higher burning-out rate, higher iron grade of the furnace slag and longer service life of the circulating pump compared with the prior art, and the application prospect is also wider.

The invention relates to the technical field of natural rubber processing, and particularly discloses a natural rubber latex preservative and a preparation method thereof. The preservative is prepared from modified nano titanium dioxide, ethylparaben, enzymolysis chitosan, immobilized lysozyme, pentaerythritol ester, sodium hydrosulfite, rosmarinic acid, potassium ferrocyanide, an acrylic acid-chitosan copolymer and the balance of deionized water. The preparation method comprises the steps of enzymolysis chitosan solution preparation and enzyme compounding, organic phase emulsification, nano component ultrasonic dispersion and vacuum defoaming aging, wherein the intermittent ultrasonic temperature control process guarantees the biological activity. The preservative can replace traditional ammonia water to be used for natural latex preservation, and has the advantages of being high in bacteriostasis and oxidation resistance synergism, high in colloid stability, environmentally friendly, safe and free of residues; according to the preparation method, through low-temperature enzyme protection and nano interface engineering innovation, the problems of biological inactivation and particle agglomeration in a traditional process are solved, and efficient and green production is achieved.

The present application relates to the technical field of industrial wastewater treatment, and specifically discloses a sodium hydrosulfite production wastewater recycling treatment method, comprising the following steps: step 1: introducing sodium hydrosulfite production wastewater into a hydrolysis unit for treatment with a degradation catalyst, so that abundant hydroxyl radicals are generated by the chelation of ferrous ions and water molecules to degrade organic matter; step 2: introducing the hydrolyzed wastewater into an oxidative degradation unit for secondary degradation treatment, so that active oxygen is generated by electrolysis and the degradation effect of hydroxyl radicals is promoted to degrade organic matter; step 3: adding the treated wastewater into a light reaction unit for degradation by microbial reaction materials, so that crude clean water is obtained through the synergistic effect of nitrifying bacteria, flocculating bacteria and modified adsorption resins; and clean water is obtained after the crude clean water is filtered. The present application performs multiple degradation on production wastewater, and the concentration of organic matter is reduced to meet the discharge standard.

The invention discloses a hexavalent chromium polluted underground water green remediation system and application. The hexavalent chromium polluted underground water green remediation system comprises a remediation well body and a non-contact sustainable electron injection system arranged in the remediation well body. The repair well main body comprises a shaft and a through hole formed in the wall of the shaft; the non-contact sustainable electron injection system comprises a medicament chamber and a graphite cathode plate; the medicament chamber is a closed space enclosed by a proton exchange membrane and a sealing plug, and a graphite anode plate and a sodium dithionite solution are accommodated in the medicament chamber; the graphite cathode plate is electrically connected with the graphite anode plate; according to the non-contact sustainable electron injection hexavalent chromium polluted underground water green remediation method, a reducing agent does not need to be added into a water-containing layer, the secondary pollution risk caused by the reducing agent and a product thereof is avoided, and green and efficient hexavalent chromium underground water remediation is achieved.

The application provides a high-concentration superfine anthraquinone cooking aid, which comprises the following components in parts by weight: 10-15 parts of sulfonated anthraquinone, 15-25 parts of anthraquinone, 2-8 parts of sodium hyposulfite, 1.0-2.0 parts of wetting agent, 0.5-2.0 parts of dispersing agent, 0.2-0.8 parts of defoaming agent, 0.5-2.0 parts of NaOH, 0.5-1.5 parts of xanthan gum, 0.5-1.0 parts of ethyl hydroxyethyl cellulose, 0.1-0.3 parts of preservative and 50-65 parts of water. The application further provides a preparation method of the high-concentration superfine anthraquinone cooking aid, which specifically comprises the following steps: S1, pre-dispersion and alkalization reaction; S2, emulsification and dispersion; S3, suspension agent compounding; S4, fine grinding; S5, suspension stabilization; and the like. The high-concentration superfine anthraquinone cooking aid prepared by the application has the advantages of excellent suspension stability in a high-concentration state and smaller particle size to realize efficient penetration and catalysis.

The utility model discloses a box for mixing detection reagents, which is characterized in that the box comprises a box body provided with a colorimetric card coating area, an alkaline liquid cavity, a sodium dithionite cavity and a urine cavity are arranged in the box body, the alkaline liquid cavity, the sodium dithionite cavity and the urine cavity are sequentially arranged, and the colorimetric card coating area is arranged in the box body. A connecting channel I is arranged between the alkaline liquid cavity and the sodium dithionite cavity, and a switch valve I and a corresponding control switch I are arranged on the connecting channel I; a second connecting channel is arranged between the sodium hydrosulfite cavity and the urine cavity, a second switch valve and a corresponding second control switch are arranged on the second connecting channel, and a urine injection hole is formed in the side wall of the urine cavity. The rapid detection kit is good in stability, simple and convenient to operate, beneficial for improving the rescue success rate of rescuing diquat and paraquat poisoning patients by primary medical workers, and meanwhile capable of being used for daily rapid detection in farmer markets and families.

The invention discloses a bio-based degradable plastic preparation method, which comprises: adding polylactic acid into dichloromethane, stirring until the system is in a transparent state, dropwise adding into an activated cellulose dispersion liquid, stirring, adding graphene oxide and a glyoxal solution, continuously stirring, adjusting the system to be acidic, stirring in an ice-water bath, heating to 100-110 DEG C, vigorously stirring, and cooling to the room temperature, thereby obtaining the bio-based degradable plastic. Performing vacuum freeze drying and crushing to obtain activated polylactic acid; the preparation method comprises the following steps: adding montmorillonite into hydrochloric acid, adding sodium dithionite, stirring, filtering, washing, adding butyl titanate, carrying out ball milling, adding water, continuously grinding, dehydrating, drying, cooling and crushing to obtain activated montmorillonite; polystyrene, polyamide, a compatilizer, an antioxidant and activated polylactic acid are stirred, activated montmorillonite is added, stirring is performed, and a premix is obtained; and carrying out extrusion granulation on the premix, carrying out hot pressing and deflation on granules, and then maintaining the pressure at 5-10MPa for 1-5 minutes to obtain the bio-based degradable plastic.

This invention relates to the field of filtration and dust removal technology, specifically disclosing a high-efficiency dust removal device and method for a sealed silo. The device includes a dust collection box fixedly installed on the outside of the top of the silo body. An air inlet pipe communicating with the silo body is fixedly installed on the lower side of the dust collection box, and a first pump body is installed outside the air inlet pipe. A horizontally arranged mounting plate is fixedly installed in the middle of the silo body, and a filter cylinder for filtering large particles is installed below it. A filter plate for filtering small particles is installed on the inner side of the middle position of the mounting plate. This high-efficiency dust removal device and method for a sealed silo employs a novel structural design. The air filtered by the filter plate enters the interior of a limiting cover. Sodium dithionite particles inside the limiting cover react with oxygen in the air (a strong reducing agent that reacts rapidly with oxygen), achieving the purpose of removing oxygen and reducing the possibility of subsequent dust explosions.

The invention discloses an ammonia leaching process of copper oxide ore, which comprises the following steps: crushing and grinding the copper oxide ore, adding an activating agent into the obtained ore pulp for activating treatment, sequentially adding ammonia liquor and sulfide for leaching treatment and precipitation reaction, and filtering, and copper sulfide concentrate and filtrate are obtained. Compared with a conventional ammonia leaching process, the ammonia leaching process of the copper oxide ore has the advantages that the copper oxide ore is sequentially subjected to crushing, ore grinding, activating treatment, leaching treatment and precipitation reaction, the copper leaching rate of the copper oxide ore can be remarkably increased, meanwhile, agent consumption and environmental pollution are reduced, and the ammonia leaching process is suitable for efficient recovery of complex and difficult-to-treat copper oxide ore; the method has the advantages of simplicity in operation, low cost, high leaching efficiency, good leaching effect, environmental friendliness and the like, and is high in use value and good in application prospect.

The invention discloses a synthesis method of 3-hydroxyazetidine hydrochloride, and belongs to the technical field of organic synthesis. According to the method, tert-butylamine and epichlorohydrin are used as starting raw materials, and a target product is prepared through three-step reaction of cyclization, acetylation and deacetylation in sequence. The method is characterized in that in the acetylation reaction step, a step-by-step strategy that hydroxyl is subjected to monoacetylation at low temperature, and then tert-butyl acetylation is carried out by heating under the conditions that Lewis acid is used for catalysis and sodium hydrosulfite is used as a binding agent is adopted; the binding agent can effectively capture fallen tert-butyl, and side reaction between the fallen tert-butyl and the intermediate is avoided. By optimizing the synthesis route and the purification process, the problems of high raw material cost, high hydrogenation deprotection safety risk, more side reactions, difficulty in intermediate purification, poor product crystallization effect and the like in the prior art are solved. The obtained product is high in purity (greater than or equal to 98%) and good in crystal form, and the whole process is good in safety, simple and convenient to operate and more suitable for industrial production.

The present application relates to the field of sewage treatment, to solve the problem that the existing water treatment agent is restricted by each other when treating organic matter and heavy metal at the same time, and provide a water treatment agent suitable for natural environment and recycling and a device specially used for recycling the water treatment agent, the water treatment agent comprises: bacteria, carrier and shell; the bacteria is loaded on the carrier; the carrier is located in the shell; the shell has a through hole; the surface of the carrier is also attached with sodium hydrosulfite and alkaline salt; the shell is chelating resin; the carrier comprises a magnetically attractable metal. The present application changes the conventional sewage treatment idea, and applies before the pesticide migrates with water, effectively avoids the spread of the pollution source, especially to the soil and groundwater. At the same time, the volume of water is reduced, and the amount of water treatment agent is reduced.

The application relates to a magnetic nano cobalt-iron-based environment-friendly material and a preparation method and application thereof, and belongs to the technical field of magnetic nano materials, and comprises the following steps: S1: in a glove box, sodium hydroxide powder, sodium hydrosulfite and ferrous chloride are uniformly mixed to obtain a solid mixture, a proper amount of deionized water is sprayed, and a nano zero-valent iron environment-friendly material is prepared under rheological phase conditions; S2: in a water bath, nitrogen is passed for 30 min, a certain amount of cobalt chloride hexahydrate is added, mechanical stirring is carried out until the cobalt chloride hexahydrate is dissolved, and the nano zero-valent iron environment-friendly material prepared in S1 is added; S3: after the reaction is completed, the stirring is stopped, the reaction product is cooled to room temperature after standing, and the reaction product is filtered under the protection of nitrogen; the separated solid product is washed, repeatedly ultrasonically cleaned until neutral, and vacuum dried to prepare the magnetic nano cobalt-iron-based environment-friendly material; the magnetic nano cobalt-iron-based environment-friendly material not only has extremely high organic matter degradation performance, but also has good environmental friendliness, realizes more efficient, low-cost removal and wastewater purification, and is used for treating and recycling cobalt-containing wastewater.

The invention provides a preparation method of spiro-structure sulfonium salt, which comprises the following steps: S1, carrying out nucleophilic substitution and oxidation reaction on (1R, 3S, 4S)-5-(2-bromo-1, 1, 2, 2-tetrafluoroethyl) bicyclo [2.2. 1] heptane-2, 3-diol and sodium hydrosulfite to obtain 2-(5, 6-dihydroxy bicyclo [2.2. 1] heptane-2-yl)-1, 1, 2, 2-tetrafluoroethane-1-sodium sulfonate, and carrying out a reaction on (1R, 3S, 4S)-5-(2-bromo-1, 1, 2, 2-tetrafluoroethyl) bicyclo [2.2. 1] heptane-2, 3-diol and sodium hydrosulfite to obtain (1R, 3S, 4S)-5-(2-bromo-1, 1, 2, 2- S2, carrying out ion exchange reaction on the 2-(5, 6-dihydroxy bicyclo [2.2. 1] heptane-2-yl)-1, 1, 2, 2-tetrafluoroethane-1-sodium sulfonate and triphenylsulfonium chloride salt to obtain triphenylsulfonium: 2-(5, 6-dihydroxy bicyclo [2.2. 1] heptane-2-yl)-1, 1, 2, 2-tetrafluoroethane-1-sulfonate; S3, carrying out ion exchange reaction on the triphenylsulfonium: 2-(5, 6-dihydroxy bicyclo [2.2. 1] heptane-2-yl)-1, 1, 2, 2-tetrafluoroethane-1-sulfonate and the triphenylsulfonium: 2-(5, 6-dihydroxy bicyclo [2.2. 1] heptane-2-yl)-1, 1, 2, 2-tetrafluoroethane-1-sulfonate to obtain 2, 2, 2-tetrafluoroethane-1-sulfonate and adamantanone formic acid are subjected to a ketal reaction under the acidic condition, and the spiro-structure sulfonium salt is obtained.

An electrochromic material and a method for preparing the anodic electrochromic material thereof. The anodic electrochromic material used in the electrochromic material is bis(dimethyldihydrophenazinyl) ether. The steps are as follows: preparing a prepolymer solution; adding the cathodic electrochromic material; adding the anodic electrochromic material, and stirring until homogeneous. The method for preparing the anodic color-changing material involves preparing a moistened 2,2'-oxobis(5,10-dihydrophenazine) from 4,4'-oxobis(1,2-phenylenediamine) and catechol. The moistened 2,2'-oxobis(5,10-dihydrophenazine) is then added to acetonitrile, sodium dithionite, sodium carbonate, methyl iodide, and methyltributylammonium chloride to obtain a crude 2,2'-oxobis(5,10-dimethyl-5,10-dihydrophenazine). The crude 2,2'-oxobis(5,10-dimethyl-5,10-dihydrophenazine) is then added to toluene and ethanol to prepare a bis(dimethyldihydrophenazinyl) ether. The advantages of this invention are that it saves on the use of anodic electrochromic materials, reduces costs, and better meets color requirements.

The application provides copper and sulfur co-lattice doped nano zero-valent iron and a preparation method and application thereof, and is based on the ironophilic and sulfurophilic properties of elements, successfully improves the copper content in the nano zero-valent iron lattice, changes the physicochemical properties, improves the stability and the removal capacity of trichloroethylene and florfenicol. When the material is synthesized, copper chloride is used as the copper source (sulfurophilic), iron trichloride is used as the iron source, and a sulfur source (sodium hydrosulfite) with ironophilic and sulfurophilic properties is added as a "bridge". Through a simple one-step method, the copper and sulfur co-lattice doped nano zero-valent iron material is synthesized by means of dissolution, mixing, stirring, drying and grinding. The crystal structure of the copper and sulfur co-lattice doped nano zero-valent iron material prepared by the application is complete, the copper and sulfur co-lattice are doped in the nano zero-valent iron, rather than forming copper elements on the surface of the iron. The sulfur content and electron transfer capacity of the copper and sulfur co-lattice doped nano zero-valent iron material are improved, and the material has superhydrophobicity. The stability of the material is significantly improved, that is, the life in water can reach more than 2 years, and after being exposed to air for 30 days, the material can maintain 80% of the zero-valent iron content and hydrophobicity. The material can also enhance the removal capacity of organic pollutants trichloroethylene and florfenicol in groundwater. The synthesis method provided by the application is simple and easy to operate, the material performance is significantly improved, can provide a new design idea for co-lattice doped iron-based nano materials, and can be applied to the remediation of contaminated groundwater.

The invention provides a composite reducing agent for bleaching titanium dioxide by a sulfuric acid method and application of the composite reducing agent, and relates to the technical field of preparation of inorganic chemical materials. The composite reducing agent is prepared from the following components in percentage by mass: 90 to 99 percent of sodium hydrosulfite and 1 to 10 percent of EDTA (Ethylene Diamine Tetraacetic Acid) disodium. The method comprises the following steps: adjusting the acid of metatitanic acid slurry, heating to 45-50 DEG C, and adding the composite reducing agent for reaction. The synergistic effect of sodium hydrosulfite and EDTA disodium is utilized, sodium hydrosulfite is mainly used for reducing Fe < 3 + > to Fe < 2 + >, EDTA disodium effectively inhibits generation of insoluble precipitates by chelating metal ions, and therefore the problem of equipment scaling is thoroughly solved while efficient bleaching is conducted. According to the method, the burning and explosion risk and irritant gas pollution of a traditional process are thoroughly eliminated, the reaction condition is mild, the iron content of the product can be reduced to 15 ppm or below, the equipment scaling amount is smaller than 5 g / m < 2 >, the cleaning period is greatly prolonged, and comprehensive benefits are remarkable.

The invention discloses a method for efficiently synthesizing aristolochic acid, and belongs to the technical field of heterocyclic compound synthesis. The invention relates to a method for efficiently synthesizing aristolochic acid, which comprises the following steps: in a phosphate buffer system, stirring and reacting aristolochic acid serving as a raw material under the action of a reducing agent until a reaction solution is clear and colorless, and purifying to obtain aristolochic acid, the reducing agent is sodium hydrosulfite or thiourea dioxide. The synthesis method disclosed by the invention has the characteristics of few by-products, simplicity and convenience in operation, mild reaction, low cost of a reducing reagent, environment friendliness and good repeatability, and has a wide application prospect.

A process for the preparation of a compound of formula (I) wherein R1 is selected from one or more of the following: alkyl, substituted alkyl, haloalkyl, cyanoalkyl, alkoxy, halogen, haloalkoxy, amino, aminoalkyl, alkylsulfonyl, arylsulfonyl, alkylsulfanyl and hydroxyl wherein n is selected from 1, 2 or 3, the process comprises reacting a compound of formula (II) with 2-haloheptafluoropropane in the presence of sodium dithionite (Na2S2O4) and an aqueous buffer, where the aqueous buffer comprises an acid and a base.

The invention provides a low-cost preparation method of sodium carboxymethyl cellulose, and relates to the technical field of sodium carboxymethyl cellulose preparation. The method comprises the following steps: taking bamboo pulp, refined cotton and wood pulp as fiber raw materials, and carrying out alkalization, etherification and neutralization, the mass fraction of the bamboo pulp in the fiber raw material is 10-50%, the mass fraction of the wood pulp in the fiber raw material is 10-50%, and the mass fraction of the refined cotton in the fiber raw material is 10-50%; the alkali liquor needs to be pretreated before alkalization by using the alkali liquor, and the pretreatment steps are as follows: mixing ethanol, isopropanol, soft water and sodium hydrosulfite, adding a sodium hydroxide solution, heating to 70-80 DEG C, keeping the temperature for 30-50 minutes, cooling to 40-50 DEG C, keeping the temperature for 20-30 minutes, and finally cooling to room temperature, thereby completing the pretreatment to obtain the pretreated alkali liquor. According to the method, the production cost can be greatly reduced on the premise that the content of sodium carboxymethyl cellulose is relatively high and the product quality is not reduced, the product quality meets the market demand, and market popularization and application are facilitated.

The invention provides a preparation method and application of a mango seed biochar / sulfurized zero-valent iron (BC / s-ZVI) composite material. The method comprises the following steps: carbonizing mango seeds to prepare biochar, putting the mango seed biochar, zero-valent iron and sodium dithionite into a ball milling tank according to a certain proportion through mechanical ball milling, then adding a morpholine ethanesulfonic acid sodium salt biological buffer solution (MES) into the ball milling tank as a grinding aid, then putting mechanical grinding balls with a certain size and mass, sealing, carrying out ball milling for 6 hours, and finally, carrying out ball milling for 2-3 hours. And centrifuging, freeze-drying, grinding and sieving to obtain the BC / s-ZVI. The maximum adsorption capacities of the BC / s-ZVI on Cd (II), Pb (II), As (III) and As (V) are respectively 31.16 mg / g, 332.2 mg / g, 109.74 mg / g and 74.68 mg / g; the BC / s-ZVI enables the effective state concentrations of As, Cd and Pb in the soil to be respectively reduced by 51.72%, 37.79% and 36.57%. The material is simple in process, can be widely applied to deep treatment of wastewater containing arsenic, lead and cadmium in industrial and mining enterprises and fixation of available arsenic, lead and cadmium in composite polluted soil, and has a wide application prospect.

The application discloses a preparation method and application of LiFePO4 / C composite material, and the preparation method comprises the following steps: adding sodium hydrosulfite into a titanium white by-product ferrous sulfate heptahydrate aqueous solution for reduction, then adding citric acid for complexation, carrying out a hydrothermal reaction on the solution after the complexation to obtain a LiFePO4 precursor, and calcining the precursor to obtain the LiFePO4 / C composite material. Through multifunctional design of raw materials, the traditional multi-step process is integrated into a reduction-complexation-hydrothermal synthesis integrated process. The improvement not only shortens the process route, but also significantly reduces the use amount of auxiliary materials and energy, thereby greatly reducing the cost of preparing the high-performance LiFePO4 / C composite material by using the ferrous sulfate of the titanium white by-product, and realizing efficient utilization of materials and energy.

This application discloses an intramolecular hydrogen bond-enhanced anthraquinone derivative, its synthesis method, and its application, relating to the field of electrochemical energy storage. The acetic acid-modified anthraquinone RH-DA or AE-DA is 2,2'-(3-carboxyl-1,8-dihydroxy-9,10-dioxo-9,10-dihydroanthracene-2,7-diyl)diacetic acid and 2,2'-(1,8-dihydroxy-3-(hydroxymethyl)-9,10-dioxo-9,10-dihydroanthracene-2,7-diyl)diacetic acid. Rhein or aloe-emodin is dissolved in NaOH, glyoxylic acid solution and sodium dithionite are added, and after stirring, sodium dithionite is added again. After stirring and cooling to room temperature, hydrogen peroxide solution and HCl solution are added, causing precipitation. After washing with HCl, the precipitate is dried in a vacuum drying oven to obtain a black-green solid RH-DA or a yellow-green solid AE-DA. Its application in alkaline aqueous organic flow batteries is also disclosed.

The invention belongs to the technical field of textile chemical industry, and particularly relates to a preparation and low-temperature bleaching method of primary-color alginate fibers, in particular to a low-temperature bleaching process. Aiming at the problems of non-uniform whiteness, large damage caused by traditional oxidation bleaching and the like of alginate fibers due to raw material difference, a reduction bleaching process is innovatively adopted, thiourea dioxide or sodium hydrosulfite is used as a bleaching agent, a mixed solution of sodium metasilicate and sodium hydroxide is used as an alkaline agent, and bleaching is performed under the conditions that the pH is 7-11 and the temperature is 40-80 DEG C. According to the method, through the synergistic effect of the alkaline agent and the bleaching agent and in combination with a calcium chloride protection mechanism, fiber damage is remarkably reduced, the whiteness is stably larger than or equal to 50, process wastewater pollution is low, and clean production is achieved. According to the invention, the technical bottleneck of alginate fiber bleaching is broken through, and the application range of alginate fiber in high-grade textiles is widened.

The present invention belongs to the field of pharmaceutical synthesis technology, and in particular to a method for preparing trimethyl phloroglucinol. The present invention provides a method for preparing trimethyl phloroglucinol, and the steps include: preparing a crude product: 1,3,5-tribromobenzene, sodium methoxide, methanol, N, N-dimethylformamide and cuprous chloride are mixed, stirred and then reacted for 6-12h, the reaction terminates, the reaction solution is transferred to a sulfuric acid solution for crystallization, and the crude trimethyl phloroglucinol product is filtered to obtain the crude product; crude product purification: the crude trimethyl phloroglucinol product and sodium dithionite are added to a recrystallization solvent, heated and stirred to dissolve it, then dropped into water for crystallization, filtered, dried, and trimethyl phloroglucinol is obtained. The preparation method step provided by the present invention is simple, and the preparation process is safe and controllable. The yield of the obtained trimethyl phloroglucinol is more than 90%, the liquid phase purity is higher than 99.9%, and the color meets the pharmacopoeia standard requirements, which is more conducive to realizing industrialized batch production.

The invention discloses a sodium dithionite preparation process waste gas filtering treatment device, and relates to the technical field of waste gas filtering treatment, the sodium dithionite preparation process waste gas filtering treatment device comprises a tank body, a plurality of waste gas filtering layers are installed on the inner wall of the tank body, and a pressurization air entraining piece is arranged between every two adjacent waste gas filtering layers. According to the invention, through the arrangement of the pressurization air entraining piece, when the movable sleeve block moves upwards, waste gas between adjacent waste gas filtering layers can enter a space defined by an inner connection corrugated sleeve, an outer connection corrugated sleeve, a pressing ring and a positioning ring through a second one-way valve; when the movable sleeve block moves downwards, a pressing ring extrudes waste gas located between an external connection corrugated sleeve and an internal connection corrugated sleeve, and at the moment, the waste gas located between the external connection corrugated sleeve and the internal connection corrugated sleeve is exhausted through a first one-way valve and a first gas guide hose, so that the impact force of the waste gas flowing towards an upper waste gas filtering layer is increased; the waste gas is prevented from remaining between the adjacent waste gas filtering layers, and meanwhile, the waste gas filtering treatment efficiency of the equipment is also improved.