65 results about "Magnesium chlorate" patented technology

The present invention provides a method of producing hydrochloric acid, comprising reacting high-temperature gaseous chlorine and water vapour in a carbon-free reverse Deacon reaction (RDR) at a temperature of from about 450 to about 750 °Celsius to produce a mixture of gases comprising hydrogen chloride and oxygen. The chlorine is produced by fusing and electrolysing sodium or magnesium chloride in solid phase. The water vapour comes from thermally decomposing a hydroxide of at least one of calcium, magnesium and iron in the absence of oxygen to produce the water vapour without any admixture of oxygen (e.g., from atmospheric air). The mixture of gases produced by the RDR is immediately contacted with liquid water to dissolve the hydrogen chloride therein, thereby producing hydrochloric acid and a stream of tail gases. Heat is extracted from the hydrochloric acid to maintain its temperature substantially constant until the stream of tail gases is no longer in contact therewith. Thus the chlorine and water vapour are both supplied to the RDR at high purity and require little, if any, preheating. Heat extracted from contacting the mixture of gases with liquid water may be used to keep the RDR within its range of operating temperatures. Oxygen can be separated from the stream of tail gases, and the oxygen-depleted stream can be recycled back to the RDR to give a high percentage conversion of chlorine to hydrogen chloride. The RDR may be uncatalysed and kept within its operating temperature range by radio-frequency volumetric heating in at least one of the IEEE Ku-, K- and Ka-bands. The invention also provides a corresponding apparatus (1h) for producing hydrochloric acid, comprising an electrolytic cell (10) for the electrolysis, a gas-tight kiln (20) for the thermal decomposition, a gas-phase reactor (30) for the RDR, and an absorber (40) for dissolving the hydrogen chloride in the liquid water. The apparatus (1h) may further comprise a separator (80) for separating the stream of tail gases into the oxygen-depleted stream and a stream of oxygen, which may be fed to a steelmaking apparatus (90), for example. The liquid water for dissolving the hydrogen chloride can come from condensing water vapour obtained by drying an aqueous solution of sodium or magnesium chloride or of sodium hydroxide. The apparatus (1h) may therefore also comprise a dryer (60) for drying this aqueous solution, and a condenser (70) for condensing the water vapour thus obtained. Sodium chloride or magnesium chloride in solid phase derived from drying the aqueous solution may be recycled back to the electrolytic cell (10). Electricity for the electrolysis can come from a renewable resource. At least some of the heat for the thermal decomposition may come from the liquid metal which is a co-product of the electrolysis. The invention is therefore highly energy efficient and requires little, if any, extra energy, apart from the electricity required for the electrolysis. The invention also uses commonly available ingredients and produces no greenhouse gases.

The present disclosure provides a board material and a preparation method thereof. The board material of the present disclosure includes: an inorganic board, the inorganic board includes a plant fiber and an inorganic material, in which the mass ratio of the inorganic material to the plant fiber ranges from 1.2 to 1.5; the raw material components of the inorganic material include a magnesium sulfate, a magnesium oxide, a magnesium chloride and a modifier, the mass ratio of the magnesium sulfate to the magnesium oxide ranges from 0.4 to 0.5; the mass ratio of magnesium chloride to magnesium oxide ranges from 0.05 to 0.15; the mass ratio of the modifier to the magnesium chloride ranges from 0.025 to 0.045; the 24 h water-absorbing thickness swelling of the inorganic board is less than or equal to 3%.

The application relates to the technical field of high polymer materials, in particular to ammonia-removing and humidity-controlling water gel as well as a preparation method and application thereof, which comprises the following raw materials: deionized water, AM, MBA, Gly, lithium chloride, 2-hydroxy-2-methyl propiophenone, magnesium chloride or magnesium oxide; the AM and the MBA are added into the deionized water, and polymerization is initiated by 2-hydroxy-2-methyl propiophenone and ultraviolet light to form a polyacrylamide network, so that the novel water gel can stably control humidity and effectively remove ammonia in long-term storage, effectively adsorb ammonia and provide molecular-level water molecules, and the required humidity of a cigar is maintained; secondly, the MBA is added into the water gel to form a more stable and porous three-dimensional crosslinking network, which can not only adjust the moisture absorption / relaxation rate of the water gel, realize humidity buffering, but also adsorb ammonia molecules through acid-base neutralization, ion exchange, hydrogen bonding, electrostatic interaction, so that the water gel can maintain the required humidity of the cigar for a long time and reduce the volatilization of ammonia.

This invention relates to the field of casting technology for sand cores and sand shells, and particularly to a method for preparing high-precision casting sand cores and sand shell components based on a coated sand process. The method includes the following steps: rinsing quartz sand and reacting it with a sodium silicate solution to obtain coated quartz sand; adding 3-aminopropyltriethoxysilane and water to the coated quartz sand in a high-speed mixer; sequentially adding modified benzoxazine resin, calcium citrate, magnesium chloride, hyperbranched polyamide, and polycaprolactone-grafted starch to obtain finished coated sand; plasma-treated chromium-12 molybdenum-vanadium mold steel to obtain an amino-modified mold; sand-jetting the finished coated sand into left / right half-shells; shaping and pre-embedding chromite sand cores with chills to obtain left / right half-shell green blanks; milling the surfaces of the left / right half-shell green blanks, coating them with resin, butt-jointing, curing, and deburring to obtain the casting sand core and sand shell. This method solves the problems of poor mechanical strength, poor high-temperature stability, low production efficiency, and poor environmental performance in high-precision casting sand cores and sand shells.

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

The present invention provides a processing kit and processing method with which it is possible to achieve sufficient sensitivity and have little variation in each collected amount of a concentrated liquid of a liquid sample. The processing kit comprises: a water absorbent polymer that absorbs water from a liquid sample containing a test substance and water; a container that accommodates the water absorbent polymer; and a collected liquid container that accommodates a collected liquid containing magnesium chloride and sodium chloride. The collected liquid is added after the liquid sample is inserted into the container.

This invention relates to the field of printed circuit board manufacturing technology and discloses a fine etching process for PCB circuit patterns. The process includes injecting a fine etching composition comprising deionized water, hydrochloric acid, copper chloride dihydrate, anhydrous magnesium chloride, p-toluenesulfonic acid monohydrate, polyethylene glycol, and 2-mercaptobenzimidazole into a circulating working tank of an etching machine; setting the temperature of the working solution in the circulating working tank; sending the substrate to be etched, after dry film development, into a spray section; activating the spray array and setting the spray pressure to etch the substrate; and rapidly rinsing the etched substrate in a deionized water washing section, followed by strong air drying to obtain the circuit pattern. This invention reduces surface tension through specific components to promote solution penetration into the microstructure, utilizes an organic corrosion inhibitor to form a stable protective layer on the trench sidewalls, and combines the vertical impact of the nozzle jet on the bottom, leveraging the difference between mechanical force and chemical adsorption force to achieve anisotropic etching, thus suppressing lateral corrosion of fine circuits.

This utility model relates to the field of wastewater treatment and resource recovery technology, specifically disclosing an integrated device for anaerobic fermentation of sludge to produce biogas and recover phosphorus, including: an anaerobic fermentation unit, a phosphorus recovery unit, a sludge treatment unit, a biogas recovery unit, a dosing unit, and a PLC control device. In this integrated device, after the phosphorus-rich supernatant released from the anaerobic fermentation unit enters the sedimentation tank, the PLC control device adjusts the pH to 8.5-9.0 according to data from a pH monitor, using a sodium hydroxide dosing machine, while simultaneously adding magnesium chloride via a magnesium chloride dosing machine. 2+ , prompting PO4 3‑ NH4 + With Mg 2+ The reaction produces struvite, which is then accelerated by adding PAM through a PAM dosing machine. Finally, the struvite is collected and dried through an inclined tube, realizing the targeted recovery and resource utilization of phosphorus in sludge. This avoids eutrophication of water bodies caused by phosphorus discharge with sludge and significantly improves the utilization rate of phosphorus resources.

The application belongs to the field of high polymer materials, and particularly discloses a modified basic magnesium carbonate and a PA12 composite material and a preparation method thereof.The preparation method of the modified basic magnesium carbonate comprises the following steps: adding sodium carbonate and magnesium chloride into a sodium hydroxide solution to perform a water bath reaction to obtain the basic magnesium carbonate; adding the basic magnesium carbonate and acrylic acid into deionized water to perform a water bath reaction to obtain acrylic acid modified basic magnesium carbonate; and adding the acrylic acid modified basic magnesium carbonate, glycidyl methacrylate and an initiator into an organic solvent aqueous solution to perform a water bath reaction to obtain the modified basic magnesium carbonate.The modified basic magnesium carbonate prepared by the application can decompose and absorb heat at high temperature, release water vapor and carbon dioxide and other non-combustible gases, dilute the oxygen concentration on the surface of the combustion object, and reduce the temperature of the combustion area, so as to play a role in flame retardation.In addition, the magnesium oxide produced by decomposition covers the surface of the material to form a protective layer, and further prevents the combustion.

This invention relates to the field of drying technology and discloses a highly hygroscopic bentonite-based mineral desiccant and its preparation method. The desiccant prepared by this invention is composed of the following raw materials in the indicated mass percentages: 20wt%-30wt% anhydrous magnesium chloride, 8wt%-12wt% silica gel, 3wt%-8wt% sodium silicate, 4.5wt%-7.5wt% potassium silicate, 5wt%-10wt% attapulgite, with the balance being modified bentonite. The synergistic effect between the components of this desiccant imparts high hygroscopicity, making it promising for applications in electronics and precision instruments, food and pharmaceutical packaging, industrial and logistics transportation, and daily necessities and warehousing.

The application provides a sulfate-reducing bacteria culture medium and application thereof, and components of the culture medium include: a carbon source, a nitrogen source, a phosphorus source, calcium chloride, magnesium chloride, an inorganic sulfur source, an organic sulfur compound with reducibility, inorganic trace elements, agar and water; wherein the mass content of the organic sulfur compound with reducibility is 5-30 mg / L, the mass content of the inorganic trace elements is 152-365 mg / L; the organic sulfur compound with reducibility includes lipoic acid and / or thiamine hydrochloride; and the inorganic trace elements include a combination of zinc elements, manganese elements, molybdenum elements and boron elements. The application introduces inorganic trace elements required by biological cell metabolism and rich sulfur electron acceptor species, promotes the growth and metabolism process of sulfate-reducing bacteria, and enables SRB cells to form visible colonies at a faster speed.

A liquid composition for use as a fertilizer is provided, the liquid composition comprising a hydrated complex of MgCl2 and urea. The hydrated complex of MgCl2 and urea may also serve as a base matrix for potassium, phosphorus, or sulfur containing fertilizers. Methods for making and using the same are also provided.

The invention relates to the technical field of chemical anticorrosion pipeline materials, and discloses an application of a novel pipeline material in an anhydrous hydrogen fluoride device, the novel pipeline material is prepared from an ethylene monomer, an alpha olefin comonomer, rutile type nanometer titanium dioxide and anhydrous magnesium chloride, the anhydrous magnesium chloride is used as a carrier to load a titanium compound to form a polymerization catalyst, and the polymerization catalyst is used as a catalyst. The nano titanium dioxide is loaded on the surface of the rutile type nano titanium dioxide; the rutile type nano titanium dioxide is used as a polymerization core to construct bimodal molecular weight distribution, and the thermal conductivity of the rutile type nano titanium dioxide is utilized to induce the tube wall to form a gradient crystal structure with the crystallinity decreasing from the outer surface to the inner surface in the forming process. Through in-situ anchoring polymerization and gradient thermal history regulation and control, synergy of high barrier property, high strength and toughness and good processability of the material is realized, the problems of permeation, swelling, cracking and failure of a lining under the working condition of anhydrous hydrogen fluoride are solved, the service life of equipment is prolonged, and the production safety is improved.

This invention discloses a method for preparing a modified aluminum-based pyrazole dicarboxylic acid framework composite water-absorbing material, relating to the field of atmospheric water-collecting and adsorbing materials. The method includes dissolving 3,5-pyrazole dicarboxylic acid, soluble aluminum salt, and an alkaline solution in deionized water and stirring to obtain a precursor solution. Method A utilizes the hydrophilic micropores of MOF-303 to forcibly disperse and confine magnesium chloride within the pores, fully releasing the high water absorption properties of the deliquescent salt while completely preventing liquefaction leakage after water absorption using the physical barrier effect of the pore walls. Method B employs in-situ co-synthesis technology to uniformly embed graphene oxide into the intercrystalline gaps of MOF-303, significantly improving its photothermal conversion efficiency without significantly affecting the material's original water absorption capacity. This results in a directional enhancement of photothermal performance and the lossless preservation of water absorption capacity, achieving directional control of the composite water-absorbing material's water absorption and photothermal conversion performance.

The application discloses a catalyst for high-density polyethylene film production and a preparation method thereof, and belongs to the technical field of olefin polymerization catalysts. The catalyst takes active magnesium chloride as a carrier, loads titanium tetrachloride active components, and adopts a specific complex internal electron donor system. (1) Tetrahydrofuran and cyclohexanone are added as pre-coordination regulators during the preparation of magnesium chloride alcohol compound; (2) the alcohol compound is dispersed in titanium tetrachloride by means of atomization spraying for low-temperature titanium loading; (3) specific combined siloxane compounds and aromatic carboxylic acid esters are added in stages during the gradient temperature rising process, and ethyl benzoate is added in batches; (4) selective passivation washing is carried out by using a toluene solution containing ethyl acetate in the washing stage. Through the synergistic effect of the four steps, the generation of super-high-activity Ti 3+ centers is selectively inhibited, and the number of polymer "fish eye" defects is greatly reduced.

A hemp-magnesium oxychloride cement composite material and a preparation method thereof, which relate to a cement composite material and a preparation method thereof. The present application aims at solving the problem that the prior art cannot reduce the damage of internal stress concentration to the mechanical strength of MOC while fully exerting the water resistance improvement effect of phosphonic acid modifier on MOC. The hemp-magnesium oxychloride cement composite material is prepared from magnesium chloride hexahydrate, magnesium oxide, diphosphoric acid and hemp straw. The method comprises the following steps: 1, uniformly mixing magnesium chloride hexahydrate, distilled water and a solution containing diphosphoric acid to obtain a mixed system; 2, dry mixing hemp straw and magnesium oxide powder, and then adding the mixture into the mixed system to stir and dissolve; and 3, solidifying. The present application is used for hemp-magnesium oxychloride cement composite material and preparation thereof.

The application discloses a kind of metal-polyphenol hydrogel dressings preparation method and its application, it is related to the technical field of biomedical materials, first preparation specified proportion ethanol aqueous solution, gallus acid is dissolved with magnesium chloride ultrasonic, ammonia water is stirred and reacted, and solid crude product is collected by centrifugation.Washing and drying are carried out to obtain purified magnesium-gallus acid nanoparticles, which are dispersed and then added to methylacrylated gelatin and photoinitiator, filtered after constant-temperature dissolution.The filtrate is blue light crosslinking solidification, washing and ultraviolet double-side sterilization, then extracted by culture medium and filtered, to obtain metal-polyphenol hydrogel dressing and corresponding extract.The application can stabilize the structure of polyphenol, realize the controlled release of active substances, and avoid the toxicity caused by the rapid release of ions.The dressing can scavenge free radicals, inhibit inflammation, promote angiogenesis and tissue regeneration, has good biocompatibility, can maintain a moist environment for the wound, accelerate wound healing and reduce scar formation.

This invention relates to the field of magnesium chloride recycling technology, specifically to a method for recycling and reusing magnesium chloride, a byproduct of maltol production. The method includes the following steps: (1) heating a magnesium chloride solution produced by Grignard hydrolysis in a first rotary kiln, and recovering the solvent and water from the magnesium chloride solution by vacuum distillation; (2) under vacuum conditions, using a transport device, sending the magnesium chloride obtained in (1) into a second rotary kiln, heating it to decompose it into magnesium hydroxide; (3) sending the magnesium hydroxide obtained in (2) into a calcination device for high-temperature calcination to obtain magnesium oxide, wherein the calcination temperature is 850℃-900℃. The method provided by this invention offers a new approach for the green and continuous recycling of magnesium chloride, a byproduct of maltol production.

The application discloses a preparation method of a photoinitiator TPO and belongs to the field of photoinitiators. The preparation method of the photoinitiator TPO comprises the following steps: carrying out chlorination reaction on diphenyl phosphoric acid and a chlorinating agent to generate diphenyl phosphinic chloride; carrying out condensation reaction on the diphenyl phosphinic chloride and 2,4,6-trimethylbenzyl magnesium chloride to obtain (2,4,6-trimethylbenzyl) diphenyl phosphine oxide; and carrying out oxidation addition reaction on the (2,4,6-trimethylbenzyl) diphenyl phosphine oxide and an oxidizing agent to obtain the photoinitiator TPO. The diphenyl phosphoric acid originally as solid waste is fully utilized, waste is turned into treasure, energy is fully utilized, environmental protection pressure is reduced, the synthesis mode of the photoinitiator TPO is expanded, and the production cost of the photoinitiator TPO is reduced, and the economic and environmental friendliness of the photoinitiator TPO makes the preparation method convenient for large-scale popularization and application.

The application discloses a carbon-based negative electrode material for flexible lithium batteries and a preparation method and application thereof, and belongs to the technical field of lithium batteries. The preparation method comprises the following steps: (1) treating eucalyptus sawdust with a treatment liquid I, drying and crushing to obtain eucalyptus wood powder, wherein the treatment liquid I is prepared from urea, potassium formate and water; (2) mixing the eucalyptus wood powder with magnesium chloride and then carbonizing to obtain a carbide; (3) treating the carbide with a treatment liquid II, wherein the treatment liquid II is prepared from 2-methyltetrahydrofuran, chlorobenzylamine, triethanolamine oleic acid soap and water; and (4) heat-treating the treated carbide to obtain the carbon-based negative electrode material for flexible lithium batteries. The application can effectively recycle eucalyptus sawdust resources, reduce the preparation cost of the negative electrode material, and the prepared carbon-based negative electrode material has good performance, high specific capacity and good cycle performance.

The utility model discloses a magnesium chloride purification filtering device relates to the technical field of industrial processing, the utility model discloses a first filter cartridge, and its top is open structure, and one side bottom of first filter cartridge is connected with feed pipe, and the upper side of other side of first filter cartridge is connected with overflow pipe, and the inside bottom side of first filter cartridge is fixed with cross -piece, stainless steel mesh tube is placed in the top of cross -piece, and the inner wall sliding connection of stainless steel mesh tube and first filter cartridge, the utility model discloses the core filter piece setting in the inside difference of device, and the stainless steel mesh tube of the utility model discloses is placed on the cross -piece in the inside of first filter cartridge, and the stainless steel mesh tube upper end is outwardly explored first filter cartridge's upper port, and the second filter material upper end is also outwardly explored second filter cartridge's upper port, and this design makes when needing cleaning or replacing filter material, does not need to stop the operation of whole filtering device, greatly improves the convenience of maintenance.

The application discloses a kind of aluminum ash efficient utilization method, after being finely ground, preheating, microwave heating oxidation denitrification is added to fluidized bed under the assistance of large particle wave-absorbing material, aluminum, aluminum nitride in aluminum ash is converted into alumina, nitrogen, after heat exchange, fluoride, chlorides and other salts are removed by microwave vacuum distillation to denitrification residue, after screening, wave-absorbing material is recycled to microwave flow chlorination deoxidation, alumina, silicon oxide and magnesium oxide in aluminum ash are converted into aluminum chloride, silicon chloride and magnesium chloride, and magnesium chloride enters tailings, and aluminum chloride and silicon chloride are recovered by multistage condensation, respectively, unreacted chlorine and carbon monoxide are recycled by multistage separation.The application uses microwave heating, without balling, oxidation denitrification, distillation desalination and chlorination deoxidation reaction rate is fast, efficiency is high, raw material is widely used, system energy utilization rate is high, can realize large-scale clean and efficient utilization of aluminum ash, with good economic benefit and social benefit.

The present application relates to a kind of preparation methods of high solubility seawater crystal, comprising the following steps: S1, the sodium chloride of predetermined proportion is mixed with calcium chloride, obtain sodium chloride-calcium chloride premix, wherein calcium chloride is screened before mixing Processed;S2, the magnesium chloride of predetermined proportion, magnesium sulfate and potassium chloride are mixed and stirred, then sodium chloride-calcium chloride premix is added, and seawater crystal is prepared after being mixed uniformly.The method can reduce the adhesion of magnesium sulfate and calcium chloride, reduce the generation of insoluble calcium sulfate, solve the existing seawater crystal dissolution problem from the root, effectively improve the solubility of seawater crystal, speed up the dissolution rate, make the ion release more uniform, solve the problem of insufficient dissolution, easy to block, the dissolution effect of finished product is better than prior art.

The application discloses a Teflon coating and a spraying process thereof, and relates to the technical field of Teflon coatings, wherein the coating is a multi-layer structure of a transition layer, a bonding layer and a functional surface layer, and is suitable for stainless steel and TC4 titanium alloy substrates. The transition layer is prepared by differential raw material electrodeposition, the bonding layer is formed by magnesium chloride to generate magnesium oxygen-based chloride bonding phases, the functional surface layer is formed by plasma spraying, and is combined with stage curing. The application is suitable for working conditions, such as cooling discs, which need to be wear-resistant and heat-stable.

This invention discloses a method for extracting high-purity ammonium tetramolybdate from a waste oil hydrogenation catalyst. S1, Primary ammonia dissolution: 28% ammonia water, water, and molybdenum acid extracted from the waste oil hydrogenation catalyst are added to a primary dissolution vessel. The mixture is stirred until the molybdenum acid is fully dissolved. The reaction time is controlled to 1 hour. The pH of the dissolved solution is 7-8. The molybdenum acid has a water content of 35% and a Mo content of 46-50%. This invention employs a stepwise deep impurity removal process of "magnesium chloride for phosphorus removal + 231 resin for vanadium removal," and sets up dual phosphorus and vanadium content detection to ensure that phosphorus <0.01g / L and vanadium <0.01g / L before proceeding to subsequent processes. The molybdenum-vanadium separation coefficient of 231 resin is much higher than that of ordinary resin, effectively avoiding impurity entrainment.

This utility model discloses a magnesium chloride melting and heat-insulating conveying device, relating to the field of magnesium chloride heat-insulating conveying technology. The utility model includes a conveying pipeline with one end at a higher position and the other end at a lower position. The device designs the conveying pipeline with one end at a higher position and the other at a lower position. Molten magnesium chloride, as a fluid with a certain mass, naturally flows from the higher position to the lower position under the action of gravity, thus realizing a power-free conveying process. The pipe wall of the conveying pipeline is constructed with placement grooves, and multiple sets of placement grooves are arranged in a ring around the cross-section of the conveying pipeline. A constant-temperature heating rod is installed inside the placement groove. The heating rod, installed in the placement groove on the pipe wall of the conveying pipeline, generates heat when energized. This heat is transferred to the conveying pipeline through heat conduction, and then to the molten magnesium chloride inside the pipeline, compensating for heat loss during the conveying process, maintaining the melting temperature of the magnesium chloride, and ensuring that the temperature drop during the conveying process meets ≤8℃.

The application discloses a high-value utilization method for smelting high-salt wastewater to prepare magnesium compounds, and belongs to the inorganic chemical field.The method comprises the following steps: using an atmospheric reaction device to mix wastewater containing ammonium and magnesium chloride with magnesium oxide slurry in parallel flow, controlling pH to be 8.5-10.5 and temperature to be 70-100 DEG C, and synchronously realizing ammonia gas volatilization recovery and precipitating and synthesizing basic magnesium chloride; after reaction, washing and solid-liquid separation, the filtrate is treated and discharged up to the standard; the filter cake is calcined to obtain magnesium oxide or is acid-dissolved to obtain magnesium sulfate, and by-products hydrochloric acid are recovered simultaneously.The application couples the wastewater ammonia removal process with the basic magnesium chloride synthesis process, realizes comprehensive recovery and high-value utilization of valuable elements in the wastewater, and has the advantages of short process, low energy consumption, high resource utilization rate, and outstanding economic and environmental benefits.

The application discloses a preparation method of a composite phase change material for solving the supercooling problem of sodium acetate trihydrate, and relates to the technical field of phase change material production, and comprises the following steps: S1, 30 g of natural crystalline bischofite is weighed, dried at 120 DEG C for 12 h, and then dissolved in 90 g of anhydrous ethanol to form a magnesium chloride solution; S2, the magnesium chloride solution is filtered by using a vacuum filtration bottle, and insoluble substances are separated; the ethanol component in the obtained solution after filtration is evaporated by using a rotary evaporator, and a precipitate, magnesium chloride hexahydrate MgCl2.6H2O, is obtained; S3, the magnesium chloride hexahydrate MgCl2.6H2O is combined with sodium acetate trihydrate SAT at an optimized mass ratio of 3:17; and S4, after complete melting and uniformity, 1% sodium polyacrylate PAAS is added as a thickening agent, and the mixture is packaged in expanded graphite EG. The method can realize effective utilization of the by-product bischofite of a salt lake, and simultaneously solve the supercooling problem of SAT.

The application discloses a method for recovering multiple metals from waste lithium batteries, comprising the following steps: S1. mixing waste lithium battery black powder with a magnesium-containing chlorinating agent, and performing roasting treatment to obtain a roasting product; S2. mixing the roasting product with a weak alkaline leaching agent, and performing leaching treatment, and after filtration, a lithium-containing solution and a filter residue are obtained; S3. adding an ammonia-carbonate-sulfite composite leaching agent to the filter residue to perform ammonia leaching treatment, and after filtration, a nickel-cobalt-rich ammonia complex leaching solution and a manganese-rich solid residue are obtained; S4. sequentially performing heating and extraction treatment on the nickel-cobalt-rich ammonia complex leaching solution, and nickel sulfate and cobalt sulfate are obtained; performing dissolution and precipitation treatment on the manganese-rich solid residue, and a manganese salt is obtained; through the synergistic coupling of magnesium chloride roasting and composite ammonia leaching, lithium is preferentially extracted, and the pre-activation of transition metal phases is realized, so that the inherent contradiction that lithium efficient extraction and nickel-cobalt efficient leaching cannot be achieved simultaneously in the existing process is successfully resolved.

The application relates to the technical field of comprehensive utilization of chemical resources, and particularly discloses a method for preparing magnesium-aluminum hydrotalcite for PVC based on by-product magnesium chloride in TBT production. The method takes by-product magnesium chloride hexahydrate in tetrabutyl tin production as raw material, first converts organic tin into inorganic tin ions through pre-oxidation, then removes impurities through the cooperation of modified activated carbon and composite complexing agent, then induces the refined magnesium chloride solution through magnesium hydroxide seeds, hydrothermally synthesizes the refined magnesium chloride solution through a composite alkali system, performs in-situ surface modification, and performs centrifugal spray drying, and finally obtains magnesium-aluminum hydrotalcite. The whole process is chemically logical and rigorous, and has strong industrialization adaptability. The method solves the industry pain points of difficult removal of organic tin residues in by-product magnesium chloride in tetrabutyl tin production, great loss of magnesium resources, and insufficient product purity, the obtained product has a regular layered structure, excellent thermal stability and good PVC compatibility, realizes closed-loop high-value utilization of industrial by-products, and has outstanding environmental and economic benefits.