2512 results about "O-Phosphoric Acid" patented technology

The invention relates to the technical field of phosphoric acid production control, solves the problem that in the prior art, accurate control over the whole process of phosphoric acid production cannot be achieved, and provides a multivariable model prediction control method and system for the whole process of phosphoric acid production. The method comprises the following steps: acquiring key process data of a plurality of process units in the whole phosphoric acid production process in real time; preprocessing the key process data to obtain real-time standardized data; establishing a soft measurement model according to a pre-collected historical standardized data set; inputting the real-time standardized data into the soft measurement model to obtain a soft measurement predicted value; constructing a multivariable dynamic model according to the historical standardized data set and the soft measurement predicted value; according to the multivariable dynamic model, in combination with a model prediction control algorithm, obtaining target set values of a plurality of preset operation variables; and according to the target set value, realizing control of the whole process of phosphoric acid production. According to the invention, accurate control of the whole process of phosphoric acid production can be realized.

The preparation method comprises the following steps: S1, preparing a phosphoric acid solution, a hydrogen peroxide solution, a Ti salt, a phosphor salt solution and a ferrite solution; s2, Ti salt and the ferrite solution are mixed, and a titanium iron salt solution is obtained; mixing the phosphoric acid solution and the phosphorus salt solution to obtain a phosphorus source solution; s3, adding the titanium iron salt solution into a reaction kettle, and adding the hydrogen peroxide solution; s4, adding the phosphorus salt solution into the reaction kettle to obtain yellow slurry; s5, after the color of the slurry is heated to be white, white slurry is obtained; s6, carrying out solid-liquid separation on the white slurry to obtain an iron phosphate dihydrate filter cake; and S7, drying and calcining the iron phosphate dihydrate filter cake to obtain the Ti-doped battery-grade anhydrous iron phosphate. The titanium-doped iron phosphate is firstly prepared by a one-step method, the pH value of the reaction system is controlled by controlling the molar ratio of the iron element to all phosphorus elements in total phosphorus, ammonium phosphate and phosphoric acid in the reaction system, and the retention of the Ti element in the finished product and the regulation and control of the iron-phosphorus ratio in a specified range are ensured.

The invention relates to the technical field of polyethylene cables, in particular to a high-strength flame-retardant polyethylene cable and a preparation method thereof.The high-strength flame-retardant polyethylene cable is composed of a copper stranded wire core and a flame-retardant protective layer on the surface of the copper stranded wire core; the flame-retardant protective sleeve is made of a high-strength flame-retardant material; the high-strength flame-retardant material comprises the following components in parts by weight: 80-100 parts of low-density polyethylene, 5-10 parts of a flame retardant, 3-5 parts of a performance additive, 1-1.5 parts of filler, 0.1-0.2 part of a voltage stabilizer, 0.1-0.5 part of an antioxidant, 0.5-1 part of an initiator and 1-5 parts of a lubricant. The amino group on the surface of the silicon dioxide carrier treated by 3-aminopropyltriethoxysilane in the modification additive can be subjected to acid-base interaction with the phosphate group of APP to form chemical bridging; the interface bonding enables the APP and the modification additive to synchronously migrate to the surface of the material during combustion to cooperatively construct a protection layer, so that the problem of protection failure caused by migration rate difference of different flame retardants in a traditional flame-retardant system is solved, and the flame-retardant performance of the cable can be greatly improved.

This invention belongs to the field of wastewater treatment technology, specifically relating to a method for removing metallic impurities from acidic copper-containing etching wastewater at room temperature and pressure. The method includes the following steps: S1, adding an oxidant to the acidic copper-containing etching wastewater to conduct an oxidation-reduction reaction, obtaining a pretreatment solution; S2, adding phosphoric acid or soluble phosphate to the pretreatment solution, adjusting the pH to 1.3-1.7 using a pH adjuster, stirring, and filtering to obtain a purified copper-containing solution. The method provided by this invention achieves high removal rates for Fe, Ni, Zn, Ca, and Mg, while maintaining a high copper ion content. It can recycle and regenerate high-purity copper salt products for application in food, cosmetics, medical, electroplating, and other fields, while also reducing hazardous waste generation, improving economic efficiency, and significantly reducing costs.

The invention relates to a compound, a preparation method, a hole transport layer material, a photovoltaic device and a photovoltaic module. R1 and R4 are respectively and independently selected from amino and derivatives thereof, hydroxyl and derivatives thereof, methoxyl and derivatives thereof, sulfydryl and derivatives thereof, methylthio and derivatives thereof, thiophene groups and derivatives thereof, phosphate groups and derivatives thereof, carboxylic acid groups and derivatives thereof, and sulfonic acid groups and derivatives thereof; r2 and R3 are independently selected from alkyl, a phosphate group and derivatives thereof, a carboxylic acid group and derivatives thereof, a sulfonic acid group and derivatives thereof, and trimethoxysilyl propyl and derivatives thereof. The material is beneficial to improving the photoelectric conversion efficiency of photovoltaic devices and photovoltaic modules.

The invention relates to the technical field of protective glue, in particular to extreme high and low temperature impact resistant UV (ultraviolet) photocuring electronic protective glue which is prepared from the following raw materials in parts by weight: 30-50 parts of synergistically modified epoxy-urethane acrylate oligomer, 20-35 parts of composite active monomer, 1.5-5 parts of composite photoinitiator and 10-20 parts of core-shell structure inorganic composite filler, 0.6 to 2.2 parts of a silane coupling agent, 0.12 to 1.1 parts of an antioxidant and 0.11 to 1 part of a leveling agent; the preparation method of the synergistically modified epoxy-urethane acrylate oligomer comprises the following steps: reacting resin acid modified epoxy resin with phosphoric acid di (hydroxyethyl acrylate) ester at 80-90 DEG C, and introducing a phosphate group to obtain a phosphate modified epoxy acrylate intermediate; the protection glue unifies rigidity, flexibility and flame retardance on the molecular level through the cooperation of the hybrid oligomer and the core-shell filler, realizes high heat conductivity, strong adhesion and extremely low internal stress, and has extreme temperature impact resistance, long-term damp-heat aging resistance and high-reliability protection performance.

The invention relates to the technical field of phosphoric acid production, in particular to an intelligent optimization management method for phosphoric acid production process parameters. Obtaining adaptive window ranges at different moments according to data change characteristics of the phosphoric acid concentration sequence; obtaining a phosphoric acid production benefit value according to the phosphoric acid concentration in the self-adaptive window range; obtaining a benefit reference value according to the phosphoric acid production benefit value in the historical batch production process; obtaining a benefit comparison value according to the phosphoric acid production benefit value at the current moment and a benefit reference value; judging whether the production process is adjusted according to the benefit contrast value; obtaining a parameter deviation coefficient according to the difference characteristic of the sulfuric acid concentration of the production process corresponding to the benefit reference value and the current production process; and according to the parameter deviation coefficient and the benefit contrast value, obtaining a phosphorite putting amount difference coefficient. According to the parameter deviation coefficient, the phosphorite feeding amount difference coefficient and the benefit contrast value, the sulfuric acid concentration or the phosphorite feeding amount at the current moment is iteratively adjusted, and the quality of the phosphoric acid production process is improved.

The invention provides a preparation method of grain size grading iron phosphate and high compaction type lithium iron phosphate. Removing impurities from the titanium dioxide byproduct ferrous sulfate, and filtering to obtain a purified ferrous sulfate base solution; the method comprises the following steps: reacting phosphoric acid with ammonia water to prepare ammonium phosphate solutions with different reaction pH values and phosphorus molar concentrations, respectively mixing the ammonium phosphate solutions with a certain amount of hydrogen peroxide, and sequentially adding an iron source, a first phosphorus salt solution, a second phosphorus salt solution and a third phosphorus salt solution into a tubular reactor for reaction to obtain iron phosphate slurry; and sequentially converting, filtering, washing, drying and calcining the completely reacted slurry to finally prepare the anhydrous iron phosphate. According to the invention, a mode of controlling solution nucleation and growth is adopted, nucleation and growth rates are controlled by preparing phosphorus salt solutions with different concentrations, size grading of precursor particles is directly realized in a synthesis reaction section, and slurry grading uniformity is further realized through aging crystal transformation. Lithium iron phosphate prepared from the iron phosphate precursor has high compaction density.

The invention belongs to the technical field of electrolyte materials, and particularly relates to a pH response biopolymer solid electrolyte as well as a preparation method and application thereof. The pH-responsive degradable biopolymer is taken as a main raw material, and one or more functional groups such as pyridine, sulfonic acid, carboxyl, tertiary amine, phosphoric acid and the like are contained. The organic acid and the organic acid salt are selected to adjust the pH value of a medium around the electrolyte, and the contraction / stretching behavior of a molecular chain is influenced by changing the ionization degree of the electrolyte, so that an interpenetrating polymer network structure is formed. The polar functional group of the biopolymer affects the migration behavior of lithium ions under different pH conditions, so that the migration rate and migration quantity of the lithium ions are increased, and the cycle performance of the battery is improved. The electrolyte is suitable for high-performance energy storage devices such as a lithium ion battery, can effectively improve the battery performance, reduces the environmental pollution, and has relatively strong green and environment-friendly advantages.

The invention discloses a preparation method and application of fine-grained melamine phosphate.The preparation method comprises the steps that after melamine, water and a composite surfactant are ultrasonically mixed to be uniform, the ultrasonic power is improved, phosphoric acid is dropwise added, then the ultrasonic power is reduced, a temperature rise reaction is conducted to obtain reaction liquid, and then the fine-grained melamine phosphate is obtained after cooling, filtering, washing and drying are conducted; wherein the composite surfactant is composed of a gemini surfactant and a polymer surfactant according to a mass ratio of (1-20): (5-40). According to the preparation method disclosed by the invention, the composite surfactant and the multi-stage ultrasonic treatment are utilized to cooperate with the mixed materials and react, so that the fine-grained melamine phosphate with the particle size of 1-4.5 microns is prepared, and the preparation method has the advantages of high reaction efficiency, simplicity in operation and the like.

The invention discloses a preparation method of a hydrofining catalyst for petrochemical engineering. The preparation method comprises the following steps: step a, carrier pretreatment: putting an aluminum oxide precursor into a dilute nitric acid solution with the mass fraction of 1-5%, dipping for 2-4 hours, and drying at 120-150 DEG C for 3-6 hours; the comprehensive performance of the catalyst is remarkably improved by modifying the alumina carrier with phosphoric acid and optimizing an active component loading process; a gradient acid center is constructed on the surface of the carrier through phosphoric acid treatment to promote adsorption and dissociation of the sulfur / nitrogen-containing compound; the dispersion degree of the active phase is enhanced and high-temperature sintering is inhibited by a bimetal synergistic loading strategy; the pore structure evolution is effectively controlled by a segmented drying and stepped heating roasting process, a through type mesoporous network is formed, and the macromolecular diffusion efficiency is improved; the obtained catalyst is improved in activity in diesel oil hydrodesulfurization, improved in mechanical strength and prolonged in service life.

The invention relates to a method for preparing lithium dihydrogen phosphate from a lithium-containing solution by using an extraction-reverse extraction technology, an extraction agent adopted in the method comprises a main extraction agent, a synergistic extraction agent and a diluent, the pKa value of the main extraction agent is 2.2-7, the synergistic extraction agent has a P = O group or a cavity diameter of 0.12-0.15 nm, the water solubility of the synergistic extraction agent is less than or equal to 50 mg / L, and the diluent is a diluent. The synergistic extraction factor R of the extraction agent is more than 100, R = Dmix / (D1 + D2), Dmix is the extraction distribution ratio of the main extraction agent to the lithium when the main extraction agent and the synergistic extraction agent are mixed according to the mass ratio of 1: 1-1: 2, D1 is the extraction distribution ratio of the main extraction agent to the lithium, D2 is the extraction distribution ratio of the synergistic extraction agent to the lithium, and the stripping agent is phosphoric acid. According to the method disclosed by the invention, by selecting the main extraction agent and the synergistic extraction agent, on one hand, lithium monohydrogen phosphate and lithium phosphate impurities cannot be generated by reaction when phosphoric acid is adopted for reverse extraction, and on the other hand, higher separation degree on sodium and potassium can be achieved during extraction, so that high-purity lithium dihydrogen phosphate can be efficiently prepared.

The invention discloses a compatible molybdenum-aluminum mixed acid etching solution which comprises the following components in percentage by mass: 4%-7% of nitric acid, 55%-65% of phosphoric acid, 17%-28% of acetic acid, 0.5%-3% of an oxidizing additive, 0.05%-5% of a metal corrosion inhibitor and 10%-20% of deionized water, and the oxidizing additive is ceric nitrate and at least one selected from sodium nitrate, potassium nitrate and ammonium nitrate; the etching liquid does not contain other organic components except for organic carboxylic acid and organic carboxylate. According to the compatible molybdenum-aluminum mixed acid etching solution, on the basis that ceric nitrate is introduced, the content of nitric acid is reduced, the nitrate ion concentration is increased by adding nitrate, the overall oxidation performance of an etching solution system is improved, the etching rate ratio of different metals is adjusted, CD-Bias is reduced, the etching dip angles of a molybdenum single layer and a molybdenum-aluminum laminated layer are controlled to be kept at 20-50 degrees, and the problem of aluminum thorns is solved. The invention further discloses a molybdenum-aluminum etching method based on the compatible molybdenum-aluminum mixed acid etching solution.

The invention provides a biochar repairing agent for marine sediments and a preparation method of the biochar repairing agent, and belongs to the technical field of repairing agents. The preparation method comprises the following steps: carbonizing straws, modifying by phosphoric acid and concentrated nitric acid, depositing ferroferric oxide-titanium dioxide, loading UiO-66-(COOH) 2 on the surface, coupling cyclodextrin-MOF and chitosan, crosslinking, performing magnet separation, washing and drying to obtain the biochar repairing agent for the marine sediments. The biochar repairing agent for the marine sediments prepared by the invention has a relatively large specific surface area and a plurality of coordination groups, can better fix heavy metal ions in the marine sediments, also has a photocatalytic degradation effect on organic pollutants, and is good in mechanical strength, easy to store and transport, safe, environment-friendly and easy to separate; wide application prospects are realized.

The invention discloses modified biogas residue-based hydrothermal carbon, a preparation method thereof and a dry digestion method for kitchen waste, and belongs to the technical field of waste organic matter recycling. The preparation method comprises the following steps: soaking biogas residues in a phosphoric acid solution to obtain pretreated biogas residues; mixing the pretreated biogas residues, transition metal salt, biochar loaded with vitamin B12 and water with the mass being 8-15 times that of the pretreated biogas residues, and performing hydrothermal reaction for 1-4 hours under the conditions that the temperature is 180-250 DEG C and the pressure is 1.5-4 MPa to obtain a hydrothermal product; and activating the hydrothermal product for 1-2 hours under the protective atmosphere of 300-400 DEG C to obtain the modified biogas residue-based hydrothermal carbon. The surface Fe-Cu composite oxide sequentially catalyzes and oxidizes H2S into elemental sulfur and sulfate ions, the vitamin B12-loaded biochar can promote MA directional proliferation, the sulfate ions can competitively inhibit SRB substrate uptake, the quantity ratio of MA to SRB is increased, and the methane production efficiency is effectively improved.

The invention belongs to the technical field of wastewater treatment, and particularly relates to a method for removing metal impurities from acidic copper-containing etching wastewater at normal temperature and pressure. The method for removing the metal impurities from the acidic copper-containing etching wastewater at normal temperature and pressure comprises the following steps: S1, adding an oxidizing agent into the acidic copper-containing etching wastewater to carry out oxidation-reduction reaction to obtain a pretreatment solution; and S2, phosphoric acid or soluble phosphate is added into the pretreatment solution, the pH is adjusted to 1.3-1.7 through a pH adjusting agent, stirring and filtering are conducted, and the purified copper-containing solution is obtained. According to the method, the removal rate of Fe, Ni, Zn, Ca and Mg is high, high-content copper ions can be kept, a high-purity copper salt product can be recycled and regenerated to be applied to the fields of food, cosmetics, medical treatment, electroplating and the like, hazardous waste can be reduced, economic benefits are improved, and cost is greatly reduced.

The invention discloses a preparation method of a multifunctional cellulose-based fiber, and belongs to the technical field of multifunctional fibers.The preparation method comprises the steps that firstly, a phosphoric acid compound and a polyphenol compound are placed in a reactor to be evenly mixed and react to obtain phosphoric acid modified polyphenol, and then the phosphoric acid modified polyphenol is subjected to wet grinding to obtain the multifunctional cellulose-based fiber; then adding the phosphoric acid modified polyphenol dispersion liquid subjected to ball milling into the cellulose-based spinning solution, finally stirring, mixing and defoaming to obtain a spinning solution containing phosphoric acid modified polyphenol, and spinning and forming to obtain the multifunctional cellulose-based fiber. The phosphoric acid modified polyphenol enables the fibers to have better flame retardance, antibacterial property, ultraviolet resistance and oxidation resistance, does not influence the softness and comfort of the fibers, has better binding force with the fibers, and ensures that the finishing effect is lasting and stable. The technology has high environmental protection property and sustainability, and is suitable for production of functional textiles, sportswear and high-performance fibers.

The invention belongs to the technical field of preparation processes of barium metaphosphate, and particularly relates to a preparation method of monodisperse micron-sized barium metaphosphate. The preparation method comprises the following steps: mixing purified barium carbonate slurry and phosphoric acid according to a certain molar ratio, reacting to obtain barium dihydrogen phosphate slurry, adding ethanol and a particle size regulating agent, uniformly mixing, and carrying out spray drying to obtain a crude product; the particle size regulating agent comprises ammonium citrate, polyalcohol and barium metaphosphate; and calcining the crude product to obtain the product monodisperse micron-sized barium metaphosphate. According to the preparation method, a small amount of particle size regulating agent and a certain amount of ethanol are added, a crude product with uniform particle size distribution is prepared under a spray drying process condition, and then calcination is performed to obtain the micron-sized barium metaphosphate with uniform particle size distribution.

The invention relates to the technical field of OLED (Organic Light Emitting Diode) manufacturing process etching processes, in particular to a silver etching solution for an OLED manufacturing process as well as a preparation method and application of the silver etching solution. The silver etching liquid comprises nitric acid, phosphoric acid, a buffer agent, a metal ion chelating agent and an ionic liquid inhibitor, the ionic liquid inhibitor comprises 1-butyl-3-methylimidazole phosphate, the metal ion chelating agent is selected from at least one of pyromellitic acid, diethylenetriamine pentaacetic acid and ethylenediamine tetramethylene phosphoric acid, and the buffer agent is selected from at least one of sodium chloride, sodium chloride and sodium chloride. The buffering agent comprises acetic acid, and all the components are prepared according to a specific mass ratio. The etching solution can balance the etching rate of silver and indium tin oxide, avoid silver residues and black spot defects, prolong the service life of the solution, reduce the use of a volatile buffer agent, adapt to the OLED fine manufacturing process, improve the product yield and reduce the production cost, and is suitable for etching of a metal substrate in the OLED manufacturing process.

The invention discloses a method for synthesizing a dichloroacetyl compound, which comprises the following steps: tetrachloroethylene and an acid are subjected to an addition reaction at 100-200 DEG C to obtain an adduct, then the adduct is subjected to an acidolysis, hydrolysis or alcoholysis reaction to obtain the dichloroacetyl compound, the acid for the addition reaction is at least one of sulfuric acid, trifluoromethanesulfonic acid, methanesulfonic acid and phosphoric acid, and the acid for the alcoholysis reaction is at least one of sulfuric acid, trifluoromethanesulfonic acid, methanesulfonic acid and phosphoric acid. The molar ratio of the tetrachloroethylene to the acid is 1: (1-10). By controlling the types of acids and increasing the temperature of the addition reaction, the addition reaction of tetrachloroethylene and acids in the absence of a catalyst is realized. Double bonds of tetrachloroethylene and hydrogen protons are subjected to an addition reaction in a strong acid environment to form a cationic intermediate, then the cationic intermediate is combined with acid radical anions to form an adduct, and the adduct intermediate is high in activity, unstable and free of separation and can be directly subjected to a hydrolysis reaction, an acidolysis reaction or an alcoholysis reaction with another substrate (such as water, acid or alcohol) respectively. The synthesis of dichloroacetyl series compounds is realized, and the route has universality and diversity.

The invention discloses a method for preparing lithium phosphate with high efficiency and low cost, which comprises the following steps: roasting spodumene concentrate and phosphoric acid, and carrying out slurrying leaching and solid-liquid separation to obtain a lithium dihydrogen phosphate solution; the method comprises the following steps: evaporating and concentrating a lithium dihydrogen phosphate solution, regulating the pH value of the lithium dihydrogen phosphate solution to 7-8 by adopting ammonia water, adding calcium phosphate seed crystals, inducing to remove residual calcium ions and magnesium ions in the solution, and carrying out solid-liquid separation to obtain a phosphate solution containing lithium ions; and then adjusting the pH value back to 11-13 by adopting alkali for lithium precipitation to obtain a lithium phosphate solid, and washing and drying to obtain a battery-grade lithium phosphate product. According to the preparation process of the lithium phosphate, the spodumene is acidized and roasted by adopting phosphoric acid, and pulpified and leached, and calcium ions and magnesium ions in a solution are directly induced by adopting calcium phosphate seed crystals to form crystals to be separated out on the basis of a weakly alkaline condition, so that the process steps are simple and convenient, the subsequent purification procedure is omitted, and the preparation process is more suitable for industrialization; meanwhile, the lithium phosphate product with high purity and high yield can be obtained through the simple and convenient process, the purity can reach 99.5% or above, and the yield can reach 92% or above.

The invention discloses a CAD detection method for phosphoric acid and phosphorous acid in an alendronate sodium oral solution, and belongs to the technical field of pharmaceutical analysis. The method comprises the following steps: preparing a reference stock solution and a test solution; then setting high performance liquid chromatography detection conditions; a Shodex VN-504D chromatographic column is adopted, a CAD detector is adopted as a detector, a mixed solution of a mobile phase A and a mobile phase B is adopted as a mobile phase, the mobile phase A is ammonium formate, the mobile phase B is an acetonitrile solution, and gradient elution is performed by adopting the mobile phase; and respectively measuring the reference stock solution and the test solution, injecting into a liquid chromatograph, and recording a chromatogram. A CAD detector is adopted, the detection sensitivity is obviously improved, the quantitative concentration can reach 0.24 mu g / mL, and the detection concentration can reach 0.10 mu g / mL. The method is high in specificity, high in sensitivity, good in durability, rapid, simple, effective and reliable.

The invention discloses an imidazole derivative-organic phosphoric acid combined extracting agent and an application method thereof, and belongs to the technical field of hydrometallurgy. The molar ratio of the imidazole derivative to the organic phosphoric acid is (10: 1)-(1: 10). The combined extraction agent can be used for extracting nickel, cobalt and manganese from a solution containing one or more nickel, cobalt and manganese. The selectivity of the solvent extraction system to nickel, cobalt and manganese is far higher than that of impurity metal ions such as calcium, magnesium, lithium, sodium and potassium, the extraction system is good in stability, free of emulsification phenomenon and third phase generation, easy to operate, low in cost and environmentally friendly. In lithium battery recovery and other systems containing coexistence of nickel, cobalt, manganese and calcium, magnesium and lithium, the solvent extraction system is particularly good in selectivity, and efficient co-extraction of nickel, cobalt and manganese can be achieved. When a mixed solution and a weak acid solution are treated, purification and concentration of target metal can be synchronously achieved, the recovery period is greatly shortened, the recovery rate is increased, and the method has great significance in efficient utilization of nickel-cobalt-manganese resources.

Disclosed is a method for removing heavy metal ions from a phosphoric acid containing stream, the method may include: adding a diluted solution of a dialkyldithiophosphate compound having an alkyl chain length ranging from 8 to 12 carbon atoms to the phosphoric acid containing stream to form a heavy metal ion complex; and separating the heavy metal ion complexes from the phosphoric acid containing stream.

The invention relates to the technical field of wet-process phosphoric acid, and discloses a wet-process phosphoric acid grading and arsenic removal treatment method and system, and the system can be switched between a parallel grading treatment mode and a series depth treatment mode through flow control; in the parallel mode, the two arsenic removal reaction tanks operate independently to respectively treat different raw materials and produce desulfurized acid for industrial monoammonium and low-arsenic dilute phosphoric acid for high-phosphorus compound fertilizer, the low-arsenic dilute phosphoric acid is mixed and blended with untreated dilute acid and then concentrated, qualified products are obtained with the minimum treatment capacity, and the cost is remarkably reduced; in the series connection mode, raw materials sequentially flow through the two tanks to be deeply purified, and single high-quality phosphoric acid is produced; the two modes are both integrated with efficient filter pressing units, solid-liquid separation is carried out on arsenic-containing thick slurry generated by arsenic removal, and phosphorus resource recovery and arsenic pollution control are achieved; the device has production flexibility and deep purification capacity, perfectly meets the requirements of raw material fluctuation and multiple products, and thoroughly solves the problem of arsenic slag disposal.

The invention relates to the technical field of heavy metal pollution treatment, and particularly discloses a biochar material and method for adsorbing heavy metals in wormcast. The biochar material for adsorbing the heavy metals in the wormcast adopts waste green tea residues as a raw material, and after being soaked in a phosphoric acid solution with the mass concentration of 38-42%, the biochar material is subjected to heat treatment at the temperature of 540-560 DEG C to obtain P-BC powder. The P-BC powder is soaked in a metal salt solution with the total metal ion concentration being 0.8-1.2 mol / L, and under the action of a precipitator, the LDH-coated P-BC material is obtained. The LDH-coated P-BC material is mixed with a ferric chloride hexahydrate solution and a NaBH4 aqueous solution for reaction to obtain the biochar material for adsorbing the heavy metals in the wormcast, so that the fixing and stabilizing effects of the biochar material on the heavy metals in the wormcast are improved.

The invention provides a separation and recovery method of a nickel-iron alloy. The separation and recovery method comprises the following steps that S1, the ferro-nickel alloy material is subjected to atmospheric pressure leaching, and leaching residues and leaching liquid are obtained; s2, mixing the leachate in the S1, phosphoric acid and a first pH regulator, regulating the pH value to 1.6-1.8, and carrying out first impurity removal treatment to obtain iron phosphate and an impurity-removed solution; and S3, adjusting the pH value of the liquid subjected to impurity removal by adopting a second pH regulator until the pH value is 2.1-2.3, and carrying out second impurity removal treatment to obtain precipitation slag and a nickel-containing solution. According to the method, under the condition that impurities in the leachate are removed through phosphoric acid, the pH value of the leachate is adjusted and controlled in two stages, so that few main metal is included in impurity precipitates, the filtering performance is good, meanwhile, the loss of the main metal in the impurity removal process is reduced, and the recovery rate of nickel in the nickel-iron alloy material is increased.

The invention relates to a method for preparing lithium phosphate from a lithium-containing solution by using an extraction-reverse extraction technology, an extraction agent adopted in the method comprises a main extraction agent, a synergistic extraction agent and a diluent, the pKa value of the main extraction agent is greater than 12.5, the synergistic extraction agent has a P = O group, a hydroxyl group or a cavity diameter of 0.12-0.15 nm, the water solubility of the synergistic extraction agent is less than or equal to 50 mg / L, the viscosity is less than or equal to 50 mpa.s, and the diluent is a diluent. The synergistic extraction factor R of the extraction agent is more than 100, R = Dmix / (D1 + D2), the Dmix is the extraction distribution ratio of the main extraction agent to lithium when the main extraction agent and the synergistic extraction agent are mixed according to the mass ratio of (1: 1)-(1: 2), the D1 is the extraction distribution ratio of the main extraction agent to lithium, the D2 is the extraction distribution ratio of the synergistic extraction agent to lithium, and the stripping agent is phosphoric acid. According to the method disclosed by the invention, by selecting the main extraction agent and the synergistic extraction agent, on one hand, lithium monohydrogen phosphate and lithium dihydrogen phosphate impurities cannot be generated by reaction when phosphoric acid is adopted for reverse extraction, and on the other hand, sodium and potassium can be separated at a higher degree during extraction, so that high-purity lithium phosphate can be efficiently prepared.

The invention belongs to the field of phosphorus chemical industry, and particularly relates to a method for synchronously preparing type II anhydrite in a semi-hydrated-dihydrated wet-process phosphoric acid process and the type II anhydrite. The method comprises the following steps: carrying out slurry premixing, semi-hydrated crystallization, dihydrate conversion and dihydrate filtration to obtain dihydrate gypsum, after the semi-hydrated crystallization step, leading out a part of slurry, adding a lattice orientation agent and a crystal face selective adsorbent into an intermediate pretreatment tank for pretreatment, and adding concentrated sulfuric acid into an anhydrous crystallization reactor for anhydrous crystallization, and finally, carrying out solid-liquid separation, washing and drying to obtain the type II anhydrite. The method is simple in process, energy-saving and environment-friendly, co-production of the phosphoric acid product and the high-added-value II type anhydrous gypsum is realized, and the product yield is gt; therefore, the method has remarkable economic benefits and environmental benefits.

The invention relates to the technical field of ardealite treatment technology, and discloses a method and a system for harmless treatment of ardealite, which are characterized in that fresh ardealite discharged by wet-process phosphoric acid filtration is re-pulped and then sequentially passes through a first-section reaction tank (added with fly ash and cement), a tank A of a second-section reaction tank, a tank B of the second-section reaction tank and a tank C of the second-section reaction tank for continuous reaction; performing solid-liquid separation to obtain harmless phosphogypsum; after the filtrate is settled, supernate is reused for repulping and lime milk preparation, and thick slurry is returned to the reaction tank; the reaction waste gas is washed with phosphoric acid acidic water, and washing liquid is reused for ore grinding; through multi-stage reaction and accurate pH control, the phosphogypsum stably reaches the class I solid waste standard, and the curing time is shortened from traditional several days to several hours; the system is deeply coupled with a front-end phosphoric acid system, and water balance and resource circulation of the system are realized by optimizing and filtering a washing water source and recycling steam condensate water; the process has the advantages of low cost, stable quality and flexible operation.