1861 results about "Ammonium sulfate" patented technology

The invention relates to the technical field of oilfield chemistry, and discloses a graft modified cellulose filtrate reducer and a preparation method thereof.The preparation method comprises the following steps that modified hydroxyethyl cellulose, 2-acrylamide-2-methyl propane sulfonic acid, dimethyl diallyl ammonium chloride, alkenylated cardanol and N, N '-methylene bisacrylamide are added into deionized water, stirring is conducted, and a mixture is obtained; the preparation method comprises the following steps: adding cellulose into a reaction kettle, stirring for 10-15 minutes at the temperature of 40-60 DEG C at the speed of 300-400 rpm, dropwise adding ammonium persulfate and sodium hydrogen sulfite into a system, and continuously reacting for 4-6 hours to obtain the grafted modified cellulose filtrate reducer. The filtrate reducer disclosed by the invention has good high temperature resistance and salt resistance.

The invention provides a polyaniline / modified graphene oxide composite material and a preparation method thereof. The preparation method comprises the following steps: dispersing purified graphene oxide, performing ultrasonic treatment, heating, adding a modifier for modification, centrifuging, taking precipitate, freezing, drying and grinding to obtain modified graphene oxide powder; mixing the powder with an aniline solution in doped acid to form a modified graphene oxide / aniline acid solution; dissolving ammonium persulfate in the doped acid to prepare an ammonium persulfate acid solution; and slowly dropwise adding the solution into the solution, carrying out in-situ polymerization, and carrying out suction filtration, washing and drying to obtain the composite material. According to the method, through chemical modification and in-situ polymerization processes, the problems that a single filler is poor in dispersity, a conductive network is discontinuous, and anti-corrosion and anti-static performance is difficult to synergistically improve are solved, and the process is simple and convenient and suitable for industrialization.

The present application discloses a method for recycling and preparing lithium iron phosphate from waste lithium iron phosphate batteries, which comprises the following steps: oxidizing and acid-leaching the recycled lithium iron phosphate battery powder to obtain acid-leached lithium solution and iron-phosphorus filter residue; adjusting the pH of the acid-leached lithium solution for purification and concentration, adding a phosphorus source and adjusting the pH to 9.5 - 10.5 to obtain solution A; subjecting the iron-phosphorus filter residue to secondary acid-leaching, iron dissolution, adding a phosphorus source and adjusting the pH to 6.5 - 7.5 to obtain solution B; mixing solution A and solution B for coprecipitation reaction, and filtering to obtain lithium iron phosphate precursor and reaction mother liquor; subjecting the lithium iron phosphate precursor to anaerobic drying, mixing with a carbon source and sintering to prepare a carbon-coated lithium iron phosphate cathode material. The method provided by the present application has the advantages of short recycling path, few reaction by-products and environmental friendliness, and can recycle all components of lithium, iron and phosphorus in the waste lithium iron phosphate battery powder. At the same time, the by-product is ammonium sulfate, a high-quality fertilizer raw material, which has great application prospects.

The invention provides loofah sponge nanocellulose hydrogel and a preparation method thereof.The preparation method comprises the following steps that anhydrous citric acid, choline chloride and water are mixed to react, and a ternary eutectic solvent is obtained; dispersing loofah sponge purified cellulose in a ternary eutectic solvent, washing and filtering a product to be neutral, dispersing the product in water, and performing ultrasonic treatment to obtain loofah sponge nanocellulose turbid liquid; dissolving sodium lignin sulfonate and lithium chloride in a sodium hydroxide solution to obtain a precursor solution; mixing the loofah sponge nanocellulose suspension with water, polyacrylamide, ammonium persulfate and N, N-methylene bisacrylamide, pouring the precursor solution into the loofah sponge nanocellulose suspension, uniformly stirring the mixture, pouring the mixture into a mold, and sealing the mold; and forming to obtain the loofah sponge nanocellulose hydrogel. The invention also provides an application of the hydrogel. The hydrogel disclosed by the invention has excellent biocompatibility, mechanical property and conductivity, has a wide application prospect in the field of flexible electronics, and is simple in preparation process, low in cost, green and environment-friendly.

The invention provides an ammonium sulfate production process control method based on model prediction, which comprises the following steps: acquiring real-time data of flue gas flow, sulfur dioxide concentration, slurry PH value and ammonia water concentration, analyzing dynamic change characteristics of the flue gas flow, the sulfur dioxide concentration, the slurry PH value and the ammonia water concentration under different coal types and load working conditions, and constructing a flue gas component mutation characteristic library; transmitting an ammonia water adding amount and / or material transfer pump rotating speed control instruction to a desulfurization tower control system, executing dynamic adjustment of an absorption circulating tank, updating real-time monitoring data, comparing output prediction results, calculating deviation, and generating an optimized future prediction sequence; and judging whether the pH value and the ammonium sulfate concentration of the absorption circulating tank can continuously meet the preset upper and lower limit range conditions in the future preset time or not by comparing the prediction result sequences before and after optimization, if so, completing a dynamic adjustment period, and if not, recalculating the adjustment value of the ammonia water addition amount and / or the rotating speed of the material transfer pump.

The invention provides a method for preparing sodium carbonate and co-producing ammonium sulfate from sodium sulfate waste salt, and relates to the technical field of chemical engineering. The method comprises the following steps: mixing sodium sulfate waste salt with water for dissolution, mixing the obtained sodium sulfate waste salt solution with an impurity removal agent for impurity removal, and mixing the obtained impurity removal solution with ammonium bicarbonate for double decomposition reaction to obtain a reaction feed liquid; carrying out primary cold separation on the reaction feed liquid to obtain first filtrate and primary sodium bicarbonate; sequentially washing, drying and roasting the primary sodium bicarbonate to obtain a sodium carbonate product; carrying out secondary cold separation on the first filtrate, carrying out solid-liquid separation to obtain a second filtrate and mixed salt, and reusing the mixed salt in the metathesis reaction; and mixing the second filtrate with an acid adjusting agent to adjust the acid, and carrying out evaporative crystallization on the obtained solution to obtain an ammonium sulfate product and an evaporation mother solution. Industrial-grade sodium carbonate and ammonium sulfate are co-produced by using sodium sulfate waste salt, sodium carbonate and ammonium sulfate meet national standard requirements, and the recovery rate of sodium sulfate is greater than or equal to 90%.

The invention provides a production process for reducing the nitrogen content in reagent-grade sulfuric acid, and relates to the technical field of sulfuric acid. Comprising the following steps: adding urea solid powder into sulfuric acid at 55-65 DEG C according to the mass ratio of urea to sulfuric acid of (0.001-0.01): 100, and stirring until the urea solid powder is completely dissolved; s100, heating the mixture in the step S100 to 83-87 DEG C in a gradient manner, adding ammonium sulfate powder according to the mass ratio of ammonium sulfate to sulfuric acid of (0.05-0.1): 100 in the heating process, and stirring to react for 0.8-1.2 hours; performing reduced pressure distillation on the sulfuric acid after the reaction in the step S200 at 80-150 DEG C, introducing inert gas in a synchronous pulse manner for purging in the heating process, repeating for 2-3 times, and collecting a main fraction; treating tail gas. According to the method, the total nitrogen content and the content of NH4 < + > ions and NO3 <-> ions in the reagent-grade sulfuric acid are effectively reduced, the electronic-grade sulfuric acid is obtained, and the yield of the sulfuric acid can reach 97.5%.

The invention relates to the technical field of functional polymer composite materials, and provides diatomite modified composite super absorbent and rapid absorbent resin and a preparation method thereof. The preparation raw materials of the diatomite modified composite high-water-absorption and rapid-water-absorption resin provided by the invention comprise acrylic acid, acrylamide, sodium hydroxide, N, N '-methylene bisacrylamide, ammonium persulfate and modified diatomite. The diatomite is modified by the silane coupling agent, the agglomeration problem of the diatomite is solved, the compatibility with organic monomers is improved, and the modified diatomite, acrylic acid and acrylamide are utilized to construct an organic-inorganic synergistic three-dimensional porous network structure, so that the resin has ultrahigh water absorption rate, rapid water absorption performance and good water retention stability. Meanwhile, the preparation method disclosed by the invention does not need nitrogen protection, has the advantages of simple process, controllable raw material cost and easiness in industrial mass production, and is suitable for multiple fields such as water-saving agriculture, soil moisturizing, landscaping and the like.

The invention relates to the field of caprolactam production, and discloses a green and efficient production process and device. The process comprises the following steps: continuously oximating cyclohexanone and hydroxylamine in a microreactor under the catalysis of mesoporous silica solid acid; carrying out gas phase rearrangement on cyclohexanone-oxime in the presence of a ZSM-5 molecular sieve under the assistance of microwaves; coupling, rectifying and purifying the crude product through a four-stage molecular sieve membrane; and performing catalytic cracking on the by-product to obtain N2 / H2O and recycling. The device comprises a micro-reaction unit, a microwave-radial reactor, a membrane coupling rectifying tower group and a tail gas cracking unit. Zero emission of ammonium sulfate is achieved, the product purity is larger than or equal to 99.95%, and energy consumption is reduced by 45%.

The invention belongs to the technical field of lithium battery positive electrode materials, and provides high-compaction-density lithium iron phosphate and a preparation method thereof.The preparation method comprises the following steps that 1, pretreated polyvinyl alcohol is added into deionized water, the temperature is increased to 80-85 DEG C, stirring is conducted, the pH value is adjusted to 10.5-11.0, epichlorohydrin is added for a reaction, aniline is added for a continuous reaction, cooling is conducted, and a product is obtained; adjusting the pH value to 1-2, adding ammonium persulfate for reaction, and dialyzing to remove impurities to obtain modified polyvinyl alcohol; step 2, adding a lithium source, an iron source and a phosphorus source into deionized water for mixing, and performing ball milling and drying to obtain a lithium iron phosphate precursor; step 3, putting the lithium iron phosphate precursor into a tubular furnace, adding an inorganic carbon source, heating for reaction, cooling and crushing to obtain primary sintered lithium iron phosphate; and step 4, mixing the primarily sintered lithium iron phosphate and the modified polyvinyl alcohol, placing the mixture in a tubular furnace, carrying out heating reaction, cooling and crushing to obtain the lithium iron phosphate.

The invention relates to the technical field of polymer photoelectric materials, in particular to a preparation method of a supramolecular gel electrolyte. The method comprises the following steps: esterifying tetraphenylethylene alcohol and methacryloyl chloride to form tetraphenylethylene methacrylate, and performing staged linear heating polymerization on the tetraphenylethylene methacrylate, 3-(methacrylamido) propyl dimethyl 3-thiopropyl ammonium oxide inner salt, acrylic acid, tetraphenylethylene methacrylate and 4-vinylpyridine under the action of ammonium persulfate to obtain a tetraphenylethylene copolymer. And finally, soaking in a lithium chloride aqueous solution to obtain the supramolecular hydrogel electrolyte. The hydrogel obtained by the invention has high mechanical strength and high ionic conductivity, and is suitable for energy storage devices such as flexible supercapacitors and the like.

The invention discloses a device for recovering ammonium sulfate through electrocatalytic reduction and a using method thereof.The device comprises a wastewater pool and an outer shell, a physical filtering bin is fixedly installed in the outer shell, a water inlet of the physical filtering bin is communicated with the wastewater pool, and a water outlet of the physical filtering bin is fixedly connected with a closed electrolytic tank; the upper end of the closed electrolytic tank is fixedly connected with an electrochemical workstation, the lower end surface of the closed electrolytic tank is fixedly provided with a lead-out port, the lead-out port is fixedly connected with a product recovery device, the product recovery device comprises a first chamber and a second chamber, and a gas diffusion port is formed between the first chamber and the second chamber; a gas diffusion film is fixedly installed in the gas diffusion opening, a product discharging opening is fixedly formed in the second cavity, a product discharging valve is fixedly installed at the product discharging opening, and the nitrate reduction device is simple in structure and convenient to use, and the nitrate reduction efficiency is greatly improved.

The invention provides a gel composite adsorbent with a foaming structure as well as a preparation method and application thereof, and the preparation method comprises the following steps: S1, dissolving acrylamide powder in deionized water, and stirring to obtain a solution A; s2, dissolving sodium alginate in the solution A for thickening to obtain a solution B; s3, transferring the solution B into an ice-water bath; s4, adding N, N-methylene bisacrylamide into the solution B, stirring until the N, N-methylene bisacrylamide is completely dissolved, then adding N, N, N ', N'-tetramethylethylenediamine, and stirring until the N, N, N ', N'-tetramethylethylenediamine is uniform to obtain a solution C; s5, adding ammonium persulfate into the solution C, and stirring until the ammonium persulfate is completely dissolved to obtain a solution D; s6, the solution D is poured into a mold and then vacuumized to form gel, and a hydrogel sample is obtained after gel forming; s7, drying the hydrogel sample, and then soaking the dried hydrogel sample in a salt solution to obtain a soaked gel material; and S8, drying the soaked gel material to obtain the finished product composite adsorbent.

The invention provides a composite synergistic system for a shale gas old well and an immovable string production increasing process. The composite synergistic system mainly comprises the following substances: 10-12% of a wetting improver; 4%-6% of a scale remover; 2%-3% of a scale inhibition dispersant; 5%-10% of a resistance-reducing discharge aiding agent; 15%-20% of a synergistic accelerant; the wetting improver is a mixture of alkyl polyglucoside, an anionic surfactant sodium dodecyl benzene sulfonate and deionized water, the content of the alkyl polyglucoside in the wetting improver is 5%-10%, and the content of the anionic surfactant sodium dodecyl benzene sulfonate is 15%-18%; the descaling agent is a mixture of sodium alpha-olefin sulfonate and nonylphenol polyoxyethylene ether ammonium sulfate, and the mass ratio of the sodium alpha-olefin sulfonate to the nonylphenol polyoxyethylene ether ammonium sulfate in the descaling agent is (2: 1)-(3: 1). According to the composite synergistic system, through combination and reuse of different materials and different doses, the multifunctional composite synergistic system integrating vibration, permeation and dispersion effects is researched and developed, and therefore immovable tubular column yield increase construction of a shale gas old well is achieved.

The utility model discloses an ammonium sulfate wastewater treatment system which comprises an ammonium sulfate wastewater storage pool used for collecting ammonium sulfate wastewater, the calcium hydroxide preparation system is used for preparing a calcium hydroxide solution, an evaporator and a first circulating heater and is used for reacting ammonium sulfate wastewater and calcium hydroxide and heating and evaporating; the first crystallizer and the second circulating heater as well as the second crystallizer and the third circulating heater are used for two times of evaporative crystallization, a final concentrated solution is filtered by the filter and then flows into the mother liquor collecting tank to facilitate wastewater treatment, and evaporated ammonia gas is absorbed by the cooling absorption tower and the condensate collecting tank to form ammonia water; and condensate water of the second heat exchanger, the first circulating heater, the second circulating heater and the third circulating heater also flows back to the condensate collecting pool. According to the wastewater treatment system, ammonium sulfate wastewater and a calcium hydroxide solution are distilled and crystallized, so that calcium sulfate and ammonia water can be recovered, and waste utilization is realized.

The invention belongs to the technical field of solar-driven interface evaporation, and particularly relates to a solar-driven interface evaporation aerogel material based on gradient modification and a preparation method and application thereof. The preparation method specifically comprises the following steps: performing cross-linking reaction on chitosan and a cross-linking agent in an organic acid aqueous solution, and performing freeze drying to obtain a chitosan matrix with a three-dimensional network structure; a pyrrole monomer is uniformly dispersed in a network structure of a chitosan matrix, then the chitosan matrix is immersed in an ammonium persulfate solution, and by controlling the oxidative polymerization degree of ammonium persulfate to the pyrrole monomer, concentration gradient distribution gradually decreasing from the surface to the inside of polypyrrole is formed in the chitosan matrix, so that the polypyrrole / chitosan composite material is obtained. The solar-driven interface evaporation aerogel material based on gradient modification is obtained. The aerogel material provided by the invention combines a photothermal effect with interface evaporation, and achieves the purpose of reasonably and efficiently utilizing solar energy resources to carry out seawater desalination.

The invention relates to the technical field of lithium recovery, and in particular to a comprehensive utilization process of low-grade clay-type lithium resources, comprising the following steps: S1. grinding raw ore into fine particles, and then sequentially performing constant temperature roasting, constant temperature acid leaching, filtering and washing to obtain leaching residue and leaching solution; S2. adding ammonium sulfate to the leaching solution, filtering to obtain a crude ammonium aluminum sulfate product and a crystallization tail liquid; S3. adding new acid and water to the crystallization tail liquid, and then using it for constant temperature acid leaching again; S4. repeating steps S1-S3 for many times to obtain a lithium-rich crystallization tail liquid; S5. concentrating the lithium-rich crystallization tail liquid, adding NaOH to remove impurities, and then evaporating and concentrating, cooling, crystallizing and filtering to obtain sodium sulfate crystals; S6. precipitating lithium carbonate on the lithium-rich crystallization tail liquid; the aluminum in the leaching solution of the invention is efficiently separated, and an ammonium aluminum sulfate product is prepared; the lithium resources are effectively enriched, and finally a green and efficient comprehensive utilization process of clay-type lithium ore with almost no tail and no wastewater discharge is realized.

The invention discloses a special slow-release compound fertilizer for corn and a preparation method thereof, the special slow-release compound fertilizer comprises the following raw materials by weight: 30-40 parts of urea, 15-20 parts of ammonium sulfate, 20-25 parts of potassium sulfate, 15-25 parts of monoammonium phosphate, 2-3 parts of a seaweed extract, 0.5-1.5 parts of polyaspartic acid, 0.5-1.5 parts of trace elements, and 0.5-1 part of a slow-release agent, the slow-release agent comprises DMPP, the trace elements comprise zinc-boron-titanium citrate, and the slow-release agent comprises potassium sulfate, potassium sulfate, potassium sulfate, monoammonium phosphate, polyaspartic acid, zinc-boron-titanium citrate. The seaweed extract comprises chitosan. DMMP is added into the formula, so that stable supply of nitrogen and synergistic yield increase benefits are achieved; the chitosan, the titanium zinc borate citrate and the polyaspartic acid are added, so that the absorption efficiency of the root system is further improved, the robust growth of corn plants is promoted together, and the acre yield and the grain quality of the corn are effectively improved.

The invention provides an acrylate assistant for PVC (polyvinyl chloride) and a preparation method of the acrylate assistant, and belongs to the technical field of acrylate assistants. The preparation method comprises the steps of nano montmorillonite functionalization, synthesis of a core layer, synthesis of a middle layer and synthesis of a shell layer. The synthesis step of the core layer comprises the following steps: adding a core layer emulsion into a reaction kettle, adding an ammonium persulfate solution for the first time, heating to 64-68 DEG C, adding an ammonium persulfate solution for the second time, and reacting for 48-55 minutes to obtain a functionalized core emulsion; the core layer emulsion is prepared from deionized water, functionalized nano montmorillonite, sodium allyloxy hydroxypropyl sulfonate, butyl acrylate, 2-ethylhexyl acrylate, hydroxyethyl methylacrylate and gamma-methacryloyloxypropyltrimethoxysilane through ultrasonic treatment, and the core layer emulsion is prepared from the deionized water, the functionalized nano montmorillonite, the sodium allyloxy hydroxypropyl sulfonate, the butyl acrylate, the 2-ethylhexyl acrylate, the hydroxyethyl methylacrylate and the gamma-methacryloyloxypropyltrimethoxysilane through ultrasonic treatment; the prepared acrylate auxiliary agent is used in PVC, the fluidity can be improved, and meanwhile the impact resistance, the strength performance and the high-temperature stability performance are enhanced.

The invention discloses an extraction method for extracting gallium from waste residues of coal gangue and bauxite, which is characterized in that metal elements such as gallium and aluminum in the waste residues can be uniformly distributed through powdering and proper mixing, ammonium sulfate is added in the roasting process, so that not only is the separation and release of gallium and aluminum realized, but also the generated ammonium sulfate gas is cooled, crystallized and recycled, and the production cost is reduced. According to the method, the process cost is reduced, acid leaching, alkaline leaching and composite extraction are adopted step by step, it is ensured that gallium is efficiently enriched and separated in all procedures, gallium oxide with the purity larger than or equal to 99.5% is finally obtained, meanwhile, residual silicon-rich residues and bauxite residues are subjected to hydrothermal crystallization to prepare molecular sieves, comprehensive utilization of waste residues is achieved, and obvious economic and environment-friendly benefits are achieved.

The present invention relates to a method for treating a bacterial infection by using Paracoccus wg1 T The invention relates to a method for treating wastewater containing high concentration of inorganic nitrogen, which belongs to the technical field of waste resource utilization and water environment treatment. T The seed liquid after culture is used to treat nitrogen-containing wastewater, and the Paracoccus wg1 of the present invention T , has a very high tolerance to high concentrations of inorganic nitrogen, and has excellent denitrification capabilities under conditions of high concentrations of inorganic nitrogen. Specifically, sodium nitrate is used as the nitrogen source, sodium propionate is used as the carbon source, NO3 ‑ When the ‑N concentration is 6258.85 mg / L‑N, 97.68 mg / L‑N of NO3 can be degraded in 48 hours ‑ -N; ammonium sulfate as nitrogen source, sodium propionate as carbon source, NH4 + When the ‑N concentration is 9326.28 mg / L‑N, 92.28 mg / L‑N of NH4 can be degraded in 48 hours + ‑N. paracoccus wg1 T Biological denitrification treatment of high-concentration inorganic nitrogen wastewater has great application prospects.

The invention relates to the technical field of polycarboxylate superplasticizers, and discloses a durability-enhanced polycarboxylate superplasticizer and a preparation method thereof.The preparation method comprises the following steps that raw materials such as a polyether macromonomer are prepared, the polyether macromonomer and the like have the requirements for purity and dosage, deionized water and the polyether macromonomer are added into a reaction kettle to form a solution A, and the solution A is prepared; and preparing an initiator solution B with the mass concentration of 10-20% from ammonium persulfate, heating to 60-80 DEG C, stirring, firstly adding 1 / 3 of the initiator solution B to react, then preparing a mixed monomer solution from acrylic acid and the like, dropwise adding the mixed monomer solution and the residual initiator solution B within 2-3 hours, carrying out heat preservation reaction, cooling, and regulating the pH value to 6-8 by using sodium hydroxide to obtain a finished product. The sulfonic acid group of the introduced sodium methallyl sulfonate functional monomer can enhance the electrostatic repulsion between water reducer molecules and cement particles, so that the dispersing performance of the water reducer is improved, the agglomeration of the cement particles can be inhibited to a certain extent, and the fluidity of concrete can be maintained.

The present invention relates to a monovalent selective cation exchange membrane and a preparation method thereof, belonging to the technical field of cation exchange membranes. The specific steps are: weighing DA and ammonium persulfate and adding them to a buffer solution to obtain a PDA coating solution, pouring the PDA coating solution on the surface of a base membrane for soaking, depositing a PDA coating on the surface of the activated base membrane to obtain membrane I; dissolving zirconium tetrachloride and 2-aminoterephthalic acid in DMF, then solvent-thermally synthesizing an amino-functionalized MOF (UIO-66-NH2) under acidic conditions, weighing PEI and MOF (UIO-66-NH2) powders and adding them to a buffer solution, then pouring them on the surface of membrane I, depositing a PEI-MOF composite coating to obtain membrane II, and air-drying membrane II to obtain a monovalent selective cation exchange membrane. It can be seen that the present invention can prepare a low-cost, highly selective, and stable-performance monovalent selective cation exchange membrane by modifying the cation exchange membrane through a simple and easy-to-operate method.

The invention discloses chitosan-based conductive hydrogel and a preparation method thereof.The method comprises the steps that chitosan is added into isopropanol, after a primary reflux reaction, an aqueous solution of 2, 3-epoxypropyltrimethylammonium chloride is added, a secondary reflux reaction continues, and quaternary ammonium chitosan is prepared; the preparation method comprises the following steps: adding quaternary ammonium chitosan into an aqueous solution of acrylic acid, stirring and dissolving, adjusting the pH value of a system to 7, then adding an aqueous solution of polyvinyl alcohol, stirring uniformly, adding ammonium persulfate and N, N '-methylene bisacrylamide, stirring and fully dissolving to obtain a hydrogel precursor; and performing polymerization treatment on the hydrogel precursor, and soaking the hydrogel precursor in a mixed solution of potassium hydroxide and zinc acetate to prepare the chitosan-based conductive hydrogel. The preparation process is simple, and the problems of insufficient conductivity, weak mechanical property and insufficient stability of the biomass-based hydrogel are systematically solved through quaternization modification, a multi-crosslinking strategy and electrolyte post-treatment.

The system comprises a mixed gas pipeline, a heat exchanger a, a heat exchanger b, a heat exchanger c and a multi-stage refrigerating unit, the heat exchanger a, the heat exchanger b and the heat exchanger c are sequentially connected in series, the multi-stage refrigerating unit feeds cold media into the heat exchanger a, the heat exchanger b and the heat exchanger c for heat exchange, and the mixed gas pipeline is communicated with the heat exchanger a; and the output ends of the heat exchanger a, the heat exchanger b and the heat exchanger c are respectively provided with a gas-liquid separation tank a, a gas-liquid separation tank b and a gas-liquid separation tank c. According to the system and the method for separating and purifying the ammonium sulfate in the electrolytic manganese residues, gaseous sulfuric acid, sulfur dioxide, ammonia gas and nitrogen in mixed gas are respectively condensed and gradually recovered by utilizing the characteristic that the boiling points of the gaseous sulfuric acid, the sulfur dioxide, the ammonia gas and the nitrogen are different, components are used for recovering the ammonium sulfate and the nitrogen, and the sulfur dioxide is separated out; the ammonium sulfate recovery efficiency reduction caused by sulfur dioxide influence is avoided.

The invention discloses a high-voltage solid capacitor positive electrode oxide film repairing electrolyte and a film coating process thereof, and belongs to the technical field of solid capacitors. The electrolyte comprises ammonium azelate, azelaic acid, ammonium dihydrogen phosphate, phosphoric acid, a reducing agent, a functional additive, ethylene glycol, deionized water and other components; the electrolyte can effectively repair the positive electrode foil oxidation film when the positive electrode foil oxidation film has defects, and the film coating process comprises the steps of acid pickling pretreatment, electrolyte repair, silane coupling agent treatment, film forming liquid impregnation and curing and the like, according to the invention, the oxidation film on the surface of the positive electrode foil is repaired through the electrolyte, and the uniform and compact protection film is formed through a film coating process, so that the mechanical strength and corrosion resistance of the oxidation film are enhanced, the leakage current value of the capacitor is effectively reduced, and the service life of the capacitor is prolonged. The performance of the capacitor is improved, and the corrosion of the external environment to the oxidation film is isolated.

The invention relates to an ultrasonic vibration assisted large-width copper plate strip continuous extrusion short-process technology, and belongs to the technical field of metal processing. A copper raw material is subjected to mechanical cleaning and then ultrasonic cleaning, and the surface cleanliness of the raw material is guaranteed; the cleaned copper raw materials are fed into continuous extrusion equipment, and ultrasonic vibration is adopted for assisting continuous extrusion; after the extruded copper plate strip is cooled, spraying a suspension containing cerium (IV)-sodium dodecyl benzene sulfonate-pyrrolidone nano aluminum oxide additive on the surface of the copper plate strip, and drying; straightening by using a multi-roll straightening machine to obtain a large-width copper plate strip; the cerium (IV)-sodium dodecyl benzene sulfonate-pyrrolidone nanometer aluminum oxide auxiliary agent is prepared from nanometer aluminum oxide, DMF (Dimethyl Formamide), sodium dodecyl benzene sulfonate, N-vinyl pyrrolidone, ammonium persulfate and cerous sulfate (IV); the copper plate strip prepared by the invention has relatively high density, relatively high tensile strength and ductility, and the mechanical property of the copper plate strip is remarkably improved.

The invention provides an amino acid compound fertilizer for improving nitrogen and phosphorus utilization rate and a preparation method. The compound fertilizer is based on urea, ammonium sulfate, monoammonium phosphate and potassium chloride according to a specific proportion, glutamic acid / glycine compound amino acid and iron, zinc and boron trace elements are added, and the 18-12-18 proportioning fertilizer with a slow release function is formed through the synergistic effect of amino acid chelation pretreatment and a high tower granulation process. Amino acid competitive inhibition phosphorus immobilization and activation of crop nitrogen metabolic pathways are utilized, a porous coating structure is constructed by means of a modified starch binder, the technical effects that the nitrogen utilization rate is increased by 4% or above and the phosphorus utilization rate is increased by 6% or above are achieved, and the bottleneck of nutrient waste of traditional balanced fertilizers is broken through.

The invention relates to a composite bone repair material, a preparation method and application, the preparation method comprises the following steps: immersing silkworm cocoons in a soap salt solution for degumming, drying to prepare degummed silk, dissolving the degummed silk in a lithium bromide solution, dialyzing for desalting, and concentrating to obtain a regenerated silk protein solution; mixing the regenerated silk fibroin solution with a gelatin solution to obtain a gel solution; mechanically shaking the gel solution, so that the gel solution is uniformly mixed, uniformly distributed bubbles are formed in the gel solution, and a silk protein / gelatin gel block is obtained; soaking and cleaning the silk protein / gelatin gel block in an ammonium sulfate solution to obtain silk protein / gelatin cross-linked gel; and freeze-drying the fibroin / gelatin cross-linked gel to obtain the fibroin / gelatin composite material. The composite bone repair material has the advantages that the composite bone repair material has a bionic porous structure, has excellent mechanical properties and also has good biocompatibility and osteogenic activity. The material can be applied to filling and regeneration repair of skull defects of the orthopedics department, the oral cavity, the plastic surgery (maxillofacial) and the neurosurgery department, and has high industrial production and clinical application prospects.

The invention discloses a preparation process of a rare earth precipitation resistant electrophoretic coating for an automobile body. The preparation process comprises the following steps: S1, preparing a stable solution; s2, preparing a rare earth chelating solution; adding lanthanum lactate into the stable solution for multiple times, and adding ammonium ceric sulfate for multiple times after the lanthanum lactate is completely dissolved; s3, preparing a resin base solution; s4, preparing mixed slurry; s5, adding a solvent and an auxiliary agent; a five-membered ring chelate with thermodynamic stability is formed by carboxyl, hydroxyl and rare earth elements in sodium citrate, rare earth ions can be tightly wrapped through strong coordination bonds, namely, empty orbits of the rare earth ions and lone pair electrons of a chelating agent form coordination bonds, so that the rare earth ions cannot be dissociated in a system, and the rare earth ions are prevented from being dissociated in the system. And a path of generating hydroxide precipitates by free rare earth ions is thoroughly blocked, so that rare earth elements are effectively ensured to be uniformly distributed in the electrophoretic paint, and the surface of a raw material treated by a subsequent electrophoresis process is more uniform.