1442 results about "Sulfate" patented technology

The invention provides a dump leaching method for improving the leaching rate of gold ore, and belongs to the technical field of mineral processing. The method comprises the following steps: firstly, separating minerals into oversize products and undersize products; mixing sodium carboxymethyl cellulose, bentonite and ferrous sulfate to obtain a mixture, and granulating the undersize product by using the mixture as a binder; and mixing the undersize product particles with the oversize product, and carrying out cyanide-free dump leaching. According to the method, through graded granulation and heap building, the problem that heap building permeability is poor due to the fact that the gold ore contains many clay minerals is solved. In the granulation stage, ferrous hydroxide colloid generated by hydrolysis of ferrous sulfate in the binder can assist ore particle agglomeration, and particle stability is enhanced; during subsequent cyanide-free dump leaching, ferrous sulfate can be used as an auxiliary reducing agent and a catalyst in a thiourea gold leaching system to promote oxidation and dissolution of gold; meanwhile, ferrous ions can adjust the oxidation-reduction potential of a system, so that the thiourea gold leaching reaction is in a more favorable potential interval, the oxidation efficiency of thiourea is improved, invalid decomposition of thiourea is reduced, and therefore the use amount of thiourea and the use amount of agents are reduced.

The invention relates to the technical field of gypsum fiberboard raw material treatment, in particular to a plant fiber for a gypsum fiberboard and a preparation method and application thereof. Compared with the prior art, the preparation method provided by the invention adopts specific process steps, plant fiber raw materials are softened by using a supersaturated calcium hydroxide solution to partially remove lignin, the treated plant fiber slurry is introduced into a sulfuric acid solution for neutralization in the water washing process, and generated nano-scale calcium sulfate particles are attached to the surfaces of the plant fibers, so that the surface of the plant fibers is uniform. The plant fiber coagulant plays a role of a coagulant during production of the gypsum fiberboard, and the plant fiber meeting the requirements of production of the gypsum fiberboard is prepared. The preparation method provided by the invention is low in cost, and the gypsum fiberboard prepared from the obtained plant fiber for the gypsum fiberboard has relatively high mechanical property indexes and meets the performance requirements of boards for building decoration.

The invention relates to the technical field of water treatment, and discloses an aluminum-based composite silicon removal agent and application thereof. The aluminum-based composite silicon removal agent comprises a component A and a component B, the component A is sodium metaaluminate; the component B comprises one or more of crystalline aluminum chloride, polyaluminum chloride and polyaluminum sulfate. The two components in the aluminum-based composite silicon removal agent can form multi-stage aluminum form distribution of'multi-core-mononuclear-colloid 'in wastewater, so that a complete silicon removal path of'pH regulation and control, charge neutralization, adsorption complexing, bridging flocculation and chemical precipitation' is constructed, and efficient removal of silicate radicals can be realized. The composite silicon removal agent does not need to accurately adjust the pH value of the system, the requirement for operation precision is low, operation is easy, and the dosage of the agent is small.

The production device comprises a base, a reaction barrel is fixedly arranged on the base, a mounting frame is fixedly arranged on the outer side of the reaction barrel, a motor is fixedly connected to the top end of the mounting frame, and a stirring device for stirring basic zirconium sulfate and tartaric acid is arranged in the reaction barrel. The feeding parts are sequentially added into the reaction barrel, and a discharging part for discharging reacted liquid is arranged in the reaction barrel; through the staggered and periodic coincidence design of discharging grooves of the inner barrel and the outer barrel in the feeding part, the rotating rod is matched to drive the outer barrel to spirally move downwards, accurate and quantitative adding of the basic zirconium sulfate solution is achieved, meanwhile, the adding time and flow of the tartaric acid solution are automatically controlled through magnetic ring adsorption of the upper barrel and the outer barrel and stored energy release of the first spring, and the feeding efficiency is improved. Manual intervention is reduced, efficiency loss caused by step-by-step feeding is avoided, and the preparation efficiency of the water repellent agent is remarkably improved.

The invention discloses a sulfuric acid residual water neutralization device, and relates to the technical field of sewage treatment. A sulfuric acid residual water neutralization device comprises a base and further comprises a transversely-arranged barrel body rotationally installed on the base, a feeding port is formed in the edge of the shaft end of the barrel body, and a driving part for driving the barrel body to rotate is arranged on the base; the transverse shaft is transversely arranged in the barrel body, the outer wall of the transverse shaft is connected with a stirring rod, the outer wall of the stirring rod is fixedly connected with a branch rod, the tail end of the stirring rod is connected with an elastic scraping plate, the outer wall of the barrel body is provided with a driving source for driving the transverse shaft to rotate, and the transverse shaft is provided with a telescopic part for driving the stirring rod to stretch out and draw back along the axis; according to the invention, the neutralization efficiency of sulfuric acid is higher, the lime and calcium sulfate precipitate are not easy to precipitate, and the lime is not easy to cake.

The invention relates to a device and a method of a high-sensitivity suspension single-droplet sensor for monitoring PM2.5 pollution, belongs to the technical field of aerosol microdroplet spectrum trace analysis, and solves the problem that ppb-magnitude gas cannot be monitored in the prior art. The method comprises the following steps: pumping aerosol into a sample cell of a droplet suspension system in a single droplet form; introducing required reaction gas into the sample pool through an atmosphere control system; scattered light signals of the single liquid drops are respectively input into the dynamic signal processing system and the microdroplet imaging system; acquiring the characteristic peak displacement change of the metal ion sensing microdroplet; establishing a gas particle distribution Mie scattering inversion model based on micro-droplet dynamic response; inverting the radius of the liquid drop according to the stimulated Raman scattering / stimulated elastic scattering signal; according to the quantitative relationship of the reaction, calculating the generation of sulfate by the droplet suspension system (sensor); and judging which gas in the actual atmosphere is a main oxidation pathway for oxidizing sulfur dioxide to generate sulfate pollutants according to a calculation result.

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 provides a method and a system for predicting the durability of an underwater non-dispersible concrete structure, and relates to the technical field of material engineering. Respectively measuring an anti-permeability vector consisting of an unsteady state chloride ion migration coefficient, an anti-permeability grade and an oxygen permeation coefficient, a freezing resistance vector consisting of a mass loss rate and a dynamic elastic modulus retention rate, and a corrosion resistance vector consisting of a mass change rate in a sulfate environment, the dynamic elastic modulus retention rate and a corrosion rate in a carbonic acid environment; a fitting formula among impermeability, freezing resistance and corrosion resistance is constructed based on a known high-durability concrete sample, and by calculating the decoupling degree of each vector combination of the concrete sample relative to the high-durability concrete sample, multi-parameter collaborative evaluation and accurate prediction of the durability of the concrete structure are realized.

The invention discloses an anti-sulfate-attack preparation method of solid waste concrete, and relates to the technical field of building materials and civil engineering, the anti-sulfate-attack solid waste concrete is prepared from the following materials in parts by weight: 100 parts of cement, 30-50 parts of composite solid waste cementing material, fly ash, steel slag micro powder and coal gangue according to a given mass ratio, 60-80 parts of modified recycled aggregate; 0.05-0.1 wt% of sodium molybdate as an erosion inhibitor. According to the invention, solid waste activation-interface reconstruction-ion competition-structure self-healing is taken as a core, synchronous spanning of solid waste concrete in the dimensions of sulfate erosion resistance, resource consumption, construction convenience and the like is realized through multi-process collaboration, and the gelation potential of solid wastes such as fly ash and steel slag is accurately excited through microwave targeted activation, so that the construction efficiency is improved. And a dense microstructure is reconstructed by combining a nano-SiO2 induced crystallization technology, so that excellent mechanical properties are still ensured when the solid waste mixing amount exceeds 70%.

The invention relates to the technical field of iron phosphate preparation, in particular to a preparation method of low-impurity iron phosphate with a high iron-phosphorus ratio, which at least comprises the following steps: preparing an iron source solution and a phosphorus source solution; mixing an oxidizing agent and a phosphorus source solution as a phosphorus source mixed solution; adding the phosphorus source mixed solution into the iron source solution, and controlling the molar ratio of iron to phosphorus to be 1: (1.1-1.3) to prepare slurry; dividing the slurry into two parts, respectively adding an impurity removal agent, and then carrying out segmented aging at 90 DEG C to prepare crystallized slurry; and filtering, washing, drying and calcining the crystallized slurry to obtain a target product iron phosphate finished product. The impurity removal agent is selected from one or more of ferrous sulfate, ferrous chloride, ferrous nitrate and ferrous oxalate. Seed crystals are formed through segmented aging crystal transformation to promote crystal growth, and autonomous grain size distribution is achieved; an impurity removing agent is added in the aging stage, impurities are reduced by using the same ion effect, the iron-phosphorus ratio is increased, and the compaction density and the electrical property of the prepared lithium iron phosphate are remarkably improved.

The present application relates to electrolytic manganese technology field, specifically to a kind of method for removing heavy metal ions in manganese sulfate solution.The method for removing heavy metal ions in manganese sulfate solution provided by the present application includes the following steps: adding oxidizing agent to pretreated manganese sulfate solution, mixing and stirring, then adjusting the pH value of solution to 5.5-6.0, filtering, to obtain the first purified manganese sulfate solution;Add sulfidation agent to the first purified manganese sulfate solution, filter, to obtain the second purified manganese sulfate solution;Add porous resin polymer to the second purified manganese sulfate solution, add the mixed solution into a sealed container, introduce nitrogen, make the pressure in the sealed container reach 1.1-1.5MPa and maintain for 2-10min, then open the air valve and release pressure instantaneously, stand, filter, fine filter, to obtain the purified manganese sulfate solution.The method provided by the present application can not only effectively remove heavy metal ions in solution, but also effectively reduce the COD value of the purified solution, reduce the loss of manganese content in solution.

The invention relates to the technical field of waste gas purification, in particular to a waste gas purification device for magnesium sulfate production. The wrinkled cylindrical filter screen is fixed on the hollow mounting disc and is used for filtering waste gas; the telescopic end of the driving air cylinder is downwards connected with a driving ring; the ends, far away from the driving ring, of the limiting curved bars are connected with vertical hinge bars, and an inclined outer pipe is rotationally connected between every two vertical hinge bars. According to the waste gas purification device for magnesium sulfate production, through the design of airflow backpressure triggering, nozzle self-adaptive approaching and vibration cooperation, when a filter screen is blocked, an arc-shaped nozzle pushes a wedge-shaped block to be unlocked through backpressure, an inner barrel drives the nozzle to approach the filter screen through a reset spring, the airflow distance is shortened, the impact pressure is improved, and sulfate scales are shattering through cooperation with a pneumatic vibrator; and the spray heads obliquely and tangentially spray air and penetrate into the valley parts of the wrinkles, cleaning dead angles are avoided, and replacement of the filter screen is greatly reduced.

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 belongs to the technical field of fine chemical organic synthesis, and discloses a synthesis method of 1, 3-propane sultone without generation of three wastes. The synthesis method comprises the following steps: by taking allyl alcohol, sulfite and hydrosulfite as raw materials, generating 3-hydroxy propanesulfonate; then removing part of water, adding a solvent A to separate out sulfite, filtering, and adding sulfuric acid into filtrate for acidification; and adding a solvent B to separate out sulfate, filtering and separating out the sulfate, and adding a dehydrating agent to carry out dehydration cyclization reaction to prepare the 1, 3-propane sultone. According to the synthesis method provided by the invention, a 1, 3-propane sultone product with the yield not lower than 95% and the purity reaching 99.9% or above and a sulfate byproduct with the purity reaching 99.6% or above can be obtained; no waste gas, waste solid or waste water is generated in the reaction process, the catalyst sulfite can be repeatedly used, and the used solvent is easy to recover and can be repeatedly used.

The invention discloses a method for preparing low-sulfate basic nickel carbonate, and belongs to the technical field of chemical engineering, a three-stage grading washing process is designed through precipitant selection and grading washing processes, each stage of washing has specific purposes and conditions, and particularly, ammonium sulfate and residual sulfate radicals are subjected to competitive reaction in secondary washing, so that the low-sulfate basic nickel carbonate is prepared. The method effectively solves the problem of high sulfate radical content of basic nickel carbonate in the prior art, improves the purity and performance of the product, and has the advantages of simple operation, low cost and the like. The process method has good application prospects and market value and is expected to be widely applied to the field of chemical material preparation.

The application relates to a method for one-step synthesis of strong magnetic hydrophobic Fe3O4 nanoparticles at low temperature and the Fe3O4 nanoparticles and application, and belongs to the technical field of nano material preparation. The method comprises the following steps: adding a ferrous sulfate solution into a mixed solution of sodium hydroxide and sodium nitrate, heating and stirring to react, adding oleic acid in the reaction process, and obtaining black Fe3O4 crystals after the reaction is completed. The saturation magnetization of the obtained strong magnetic hydrophobic Fe3O4 nanoparticles can reach 85.69 emu / g at most, and the water contact angle can reach 148.95 DEG. The one-step synthesis reaction only needs to use oleic acid as a regulator, avoids an extreme high-temperature and high-pressure environment, does not need to use a toxic chemical solvent, the condition is mild, the process is simple, the operation condition is easy to control, and the method has a wide application prospect.

The invention discloses an end point identification method for precipitation reaction in rare earth sulfate production, which belongs to the field of intelligent monitoring control, and comprises the following steps: receiving potential information through a server, sequentially controlling the addition amount of hydrogen peroxide and ammonia water according to the information, and sequentially identifying a hydrogen peroxide reaction end point and a final reaction end point. The reaction endpoint can be accurately identified, so that the reaction can be terminated in time, and the purity of the rare earth sulfate is finally improved.

The application provides a kind of superfine copper powder and its preparation method and application, the preparation method of the above-mentioned superfine copper powder uses two-step liquid phase reduction method to prepare superfine copper powder, and improves process conditions, using dropwise feeding mode. Among them, the first step uses alkaline ascorbic acid solution to reduce copper chloride to cuprous chloride with narrow particle size distribution; the second step uses ferrous sulfate and sodium citrate as mixed reducing agent, and sodium citrate can also be used as a complexing agent, which helps to reduce the cuprous chloride to spherical, well-dispersed, uniform particle size distribution of superfine copper powder. At the same time, the raw materials used by the application are easy to obtain, the reaction process is mild, and organic solvents and toxic and hazardous reagents such as sodium borohydride and hydrazine hydrate are not needed, the preparation process has cost effectiveness, is friendly to the environment, and is suitable for industrial production.

The invention relates to the field of material science and geotechnical engineering, in particular to an active fault zone grouting material based on complex crystallization-calcium-based self-repairing and a preparation method and application thereof. Comprising solid components and is prepared from the following components in parts by mass: 50 to 60 parts of cement, 5 to 8 parts of silica fume, 15 to 20 parts of superfine slag powder, 0.3 to 0.5 part of a complexing agent, 0.2 to 0.3 part of monopotassium phosphate, 2 to 3 parts of calcium-based microcapsules, 0.0001 to 0.00025 part of graphene oxide and 3 to 5 parts of silica sol; the calcium-based microcapsule is of a microcapsule structure formed by wrapping a core material with a wall material, and the core material is a mixture of calcium aluminate and calcium sulfate. The grouting material provided by the invention can solve the problems that an active fault zone grouting material is weak in deformation resistance, depends on manpower in repairing and is short in service cycle, provides a long-acting, intelligent and economical solution for cross-fault zone engineering, and promotes geotechnical engineering materials to develop towards the direction of self-repairing and high durability.

The invention discloses a method for separating and recycling phosphorus, iron and lithium in battery black powder, and relates to the technical field of battery recycling. The method comprises the following steps: mixing and leaching battery black powder and sulfuric acid, and filtering to obtain a leaching solution; the pH of the leachate is controlled, ferrous sulfate in the solution is separated out through alcohol substances or ammonium sulfate, and ferrous sulfate precipitates or ammonium ferrous sulfate crystals and mother liquor are obtained after filtration; evaporating and concentrating the mother liquor, adding an impurity removing agent into the mother liquor, and extracting to obtain a phosphoric acid solution and a lithium-containing solution; after phosphoric acid is supplemented into the lithium-containing solution, the pH is adjusted to be 8-10, and battery-grade lithium phosphate precipitates are obtained. According to the method, iron in the leachate is separated out firstly, and the subsequent impurity removal difficulty is greatly reduced, so that recycling of three elements including phosphorus, iron and lithium in the battery black powder is facilitated, and the environmental problem caused by stacking of lithium extraction residues can be avoided.

The application provides a high-value recycling method of rare earth oxalate precipitation wastewater, and the method comprises the following steps: (1) under the condition of field strengthening, mixing the rare earth oxalate precipitation wastewater and an alkaline calcium salt, and obtaining a calcium oxalate precipitation and a calcium salt solution after neutralization reaction; (2) under the condition of field strengthening, mixing the rare earth chloride and the calcium oxalate precipitation, and obtaining a rare earth oxalate precipitation and a calcium chloride solution after displacement reaction; (3) mixing the rare earth sulfate, the calcium salt solution and the calcium chloride solution, and obtaining a calcium sulfate precipitation and a rare earth chloride solution after precipitation reaction. The method provided by the application not only realizes harmless treatment of the rare earth oxalate precipitation wastewater, but also realizes high-value recycling of the oxalic acid resources in the wastewater, and high-value building material calcium sulfate is prepared, waste is turned into treasure, cost is reduced and benefit is increased, and no salt-containing wastewater is discharged, so that the method is a new green and low-cost rare earth oxalate precipitation wastewater resource recycling technology, and promotes green and sustainable development of the rare earth industry.

The invention provides a manganese-doped ferrocobalt oxide nano particle-coated carbon-nitrogen cubic composite material as well as a preparation method and application of the manganese-doped ferrocobalt oxide nano particle-coated carbon-nitrogen cubic composite material. The preparation method comprises the following steps: firstly doping ferrous sulfate and manganese chloride into ZIF-8, then mixing the ZIF-8 with cobalt nitrate and 2-methylimidazole in methanol, carrying out centrifugal separation to obtain a product, and finally carrying out one-step calcination to realize carbonitriding of the composite material, doping of manganese and generation of nano particles from ferrocobalt oxide. And finally, the manganese-doped ferrocobalt oxide nanoparticle-coated carbon-nitrogen cubic composite material is obtained. Compared with the traditional preparation method, the method disclosed by the invention is simple, mild in reaction condition and high in yield, and the prepared composite material is uniform in morphology and has excellent electro-catalytic performance on the water electrolysis oxygen evolution reaction.

The invention discloses a hydro-upgrading catalyst as well as a preparation method and application thereof, and belongs to the technical field of coal chemical industry. The catalyst comprises active metal and a carrier, wherein the active metal is loaded on the outer surface and in a pore channel of the carrier; the active metal comprises a first active metal and a second active metal; the first active metal comprises metal Ni or metal Co; the second active metal comprises metal Mo or metal W; the carrier comprises a mixture of pseudo-boehmite and a modified molecular sieve; the modified molecular sieve is obtained by modifying a molecular sieve with a modifier; the modifier is selected from at least one of boric acid, zirconium sulfate and magnesium sulfate. According to the novel hydro-upgrading catalyst provided by the invention, the acidity of the molecular sieve is moderately inhibited and the cracking ability of the catalyst is limited by introducing the specific modifier into the molecular sieve, so that the mitigation of hydrocracking is facilitated; the hydro-upgrading catalyst is reasonable in acid property, moderate in cracking activity and stable in pore structure.

The invention belongs to the field of industrial environment-friendly processes, and provides a process for preparing a powdery anhydrous accelerator by synergistic resource treatment of organic waste sulfuric acid and aluminum ash, which comprises the following steps: extracting aluminum ash, denitrifying and desalting, adjusting the acidity of waste sulfuric acid, calcining and reacting at high temperature, treating calcined waste gas and preparing the anhydrous accelerator. In a high-temperature state, sulfuric acid and metal oxides in the aluminum ash generate composite sulfate, and if the waste sulfuric acid contains organic matters, the organic matters are firstly combusted and removed; fluorine in the aluminum ash exists in the form of fluoride salt; adding magnesium sulfate, sodium fluosilicate and the like into the clinker, and uniformly mixing in a mixer to obtain the powdery anhydrous accelerator. The method is reasonable in design, capable of achieving co-processing, resource utilization and energy recovery, environmentally friendly, stable in process, diversified in product and suitable for large-scale popularization.

The invention discloses a method for recovering manganese from manganese-iron alloy waste residues, which comprises the following steps: crushing the manganese-iron alloy waste residues, drying, uniformly mixing the dried manganese-iron alloy waste residues with a binary flux according to a mass ratio of 1: (1.8-2), completely roasting, cooling to room temperature, and taking out a roasted slag sample, thereby obtaining the manganese from the manganese-iron alloy waste residues. Adding deionized water to leach manganese sulfate at room temperature, filtering and separating to obtain a manganese sulfate crude solution; and adding metal manganese powder, ammonium sulfide and a flocculating agent into the manganese sulfate crude liquid, further removing impurities, adjusting the pH value, adding citric acid, and filtering and separating to obtain a manganese sulfate purified liquid. The recovery rate of manganese can reach 99.1% or above, energy consumption is low, operation is easy, impurity removal is thorough, and the obtained product is high in quality.

The invention discloses a method for improving copper plating uniformity of a circuit board. The method comprises the following steps: performing surface treatment on a drilled circuit board; the circuit board is placed in the electroplating solution to be electroplated, and the technological conditions are that the temperature of the electroplating solution is 20-30 DEG C, and the current density is 1.5-2.5 A / dm < 2 >; the main chemical components of the electroplating solution comprise copper sulfate pentahydrate, sulfuric acid, hydrochloric acid and an additive, the concentration of the copper sulfate pentahydrate is 200-250 g / L, the concentration of the sulfuric acid is 50-70 g / L, and the concentration of chloride ions is 70-90 ppm. According to the method for improving the copper plating uniformity of the circuit board, by optimizing the components of the electroplating liquid and the parameters of the electroplating process, a plating layer is more uniform, the copper thickness range inside and outside holes is controlled to be about 8.0 microns, and the requirements of high-reliability PCBs (such as HDI and carrier plates) with the thickness-diameter ratio larger than 8: 1, such as 5G communication backboards and the like are met.

The invention belongs to the technical field of soil improvement, and relates to a modified charcoal-polyaluminum ferric sulfate modifier and a preparation method thereof, and the preparation method specifically comprises the following steps: step 1, preparing charcoal; step 2, modifying the biochar; 3, preparing an aluminum-iron mixed solution; step 4, preparing polyaluminum ferric sulfate; step 5, preparing the modified charcoal composite polyaluminum ferric sulfate saline-alkali soil modifier; through multi-component compounding, nano modification, waste recycling and precise process control, the defects of single effect, high cost, poor timeliness, environmental risk and the like of the existing saline-alkali soil improver are comprehensively overcome. The core innovation point is that functional modification of biochar is combined with chemical characteristics of polyaluminum ferric sulfate, and a complex microbial inoculant is introduced to enhance biological activity, so that high efficiency, economical efficiency and environmental friendliness of saline-alkali soil improvement are realized.

The invention relates to the technical field of air filter elements, in particular to an iron-manganese-based filter element material for catalyzing and purifying VOCs (volatile organic compounds) at room temperature and a preparation method of the iron-manganese-based filter element material. The iron-manganese-based filter element material for catalyzing and purifying the VOCs at the room temperature is prepared from the following raw materials in parts by mass: 20 to 30 parts of ferrous sulfate, 30 to 40 parts of manganese sulfate, 0.1 to 1 part of ceric ammonium nitrate, 1 to 2 parts of hexadecyl trimethyl ammonium bromide, 1 to 3 parts of urea steam, 5 to 15 parts of attapulgite clay, 1 to 5 parts of aerogel aid and 1 to 5 parts of sodium alginate. The preparation method is simple, the adsorption capacity and the adsorption capacity of indoor volatile organic pollutants such as formaldehyde are greatly improved, the formaldehyde removal efficiency can be improved, the service life of the material can be prolonged, and the material is suitable for large-scale popularization and application.

The invention relates to the technical field of chemical synthesis, and discloses a method for preparing 2, 5-furandicarboxylic acid, which comprises the following steps: dispersing cobalt nitrate and nickel sulfate into an aqueous solution of polyvinylpyrrolidone at room temperature; adding a sodium borohydride solution to obtain nano colloid; preparing an aqueous suspension of cerium oxide, and adding the aqueous suspension into the nano colloid; centrifugally filtering, and recovering a solid product; washing the solid product; centrifuging, putting solid powder obtained after centrifuging into a drying oven, and drying; and calcining and grinding the solid powder to finally prepare the Co-Ni / CeO2 catalyst. And dissolving 5-hydroxymethylfurfural in water at normal temperature, adding the prepared Co-Ni / CeO2 catalyst and a sodium hypochlorite solution, reacting, and filtering to remove the catalyst, thereby obtaining the 2, 5-furandicarboxylic acid. The method disclosed by the invention has the advantages of no use of strong base, low reaction temperature, short reaction time, few byproducts, greenness and sustainability.

Disclosed are methods and systems for capturing carbon dioxide and utilizing calcium sulfate to generate useful products.