250 results about "Acid dissolution" patented technology

The invention relates to the technical field of hydrometallurgy production, and particularly discloses a method for synergistically extracting gallium and scandium by coupling titanium white waste acid with vanadium extraction converter sludge, which comprises the following steps: mixing titanium white waste acid and vanadium extraction converter sludge in proportion, stirring and leaching to obtain a leaching solution; adding an extraction agent and a diluent into the leaching solution for extraction, and washing to obtain a gallium and scandium loaded organic phase; a first stripping agent is added into the loaded organic phase of gallium and scandium for stripping treatment, and a gallium stripping solution and a loaded organic phase of scandium are obtained; sequentially carrying out alkali precipitation, alkali dissolution and electrolytic treatment on the gallium reverse extraction solution to obtain crude gallium; a second stripping agent is added into the scandium-loaded organic phase for stripping treatment, and a scandium precipitation solution and an organic phase solution are obtained; and the scandium precipitation solution is filtered, washed and subjected to acid dissolution, and a scandium-containing solution is obtained. According to the method, the titanium white waste acid is effectively recycled, rare and precious metals in the vanadium extraction converter sludge are efficiently and synergistically extracted, and the method has a relatively good popularization prospect.

The invention discloses a nickel-iron alloy dissolving method which comprises the following steps: feeding a copper sulfate solution into a mixed feed liquid containing a first nickel-iron alloy and copper sulfate, carrying out primary replacement reaction to obtain copper-containing slag and a reaction liquid, maintaining c (Fe < 2 + >) / c (Cu < 2 + >) in the reaction liquid to be 50-90, and overflowing to obtain a nickel-iron-copper solution; wherein c (Fe < 2 + >) and c (Cu < 2 + >) are mass concentrations of Fe < 2 + > and Cu < 2 + > respectively, and the unit is g / L; and carrying out secondary replacement reaction on the nickel-iron-copper solution and a second nickel-iron alloy until the concentration of Cu < 2 + > in a liquid phase is lower than 5ppm, and carrying out solid-liquid separation to obtain a nickel-iron solution product and second copper-containing slag. According to the dissolving method of the ferro-nickel alloy, the recovery process of ferro-nickel in the ferro-nickel alloy can be simplified, the quality of the ferro-nickel solution is improved, the gas production phenomenon caused by acid dissolution is avoided, and the safety is higher.

The invention provides a gold ore phase analysis method, and belongs to the field of mineral analys.The gold ore phase analysis method comprises the steps that a gold ore sample is prepared into ore pulp, the pH value is adjusted to 10-11, ultrasonic cavitation treatment is conducted after polyethylene glycol is added, and limonite turbid liquid and sedimentation bottom mud are obtained through separation; the turbid liquid is subjected to flocculation precipitation, drying, roasting, acid dissolution and impurity removal, and the limonite gold-loaded grade is obtained through the mass difference before and after dissolution and gold concentration determination; separating metal sulfide ore heavy minerals and gangue minerals from the settled bottom mud through artificial heavy elutriation, performing acid dissolution and impurity removal on the metal sulfide heavy minerals, and calculating the gold loading grade of the metal sulfide heavy minerals through mass difference and gold concentration determination; after gangue minerals are subjected to oxidizing roasting, the gold content is measured after concentrated acid dissolution; and calculating the distribution rate of gold based on the result. The gold loading grade and distribution of the limonite phase, the metal sulfide ore phase and the gangue mineral phase are measured in a split-phase mode, the method is highly matched with the gold ore development process, operation is easy and convenient, the result is reliable, and beneficiation and metallurgy technological process formulation and technical index pre-judgment can be effectively served.

The invention belongs to the field of hydrometallurgy, and particularly provides an ionic type rare earth ore leachate composite precipitation treatment method which comprises the steps that magnesium oxide is adopted for one-step precipitation of rare earth leachate, and rare earth and impurities are co-precipitated to form an enriched product; carrying out acid dissolution treatment on the rare earth enrichment, carrying out solid-liquid separation to obtain filter residues, using the filter residues for mining and covering soil, neutralizing and removing impurities from the filtrate by adopting magnesium oxide or the rare earth enrichment, adjusting the pH value of one part of the filtrate after impurity removal by adopting magnesium oxide, and sufficiently aging to serve as a precipitator for later use; the pH of the other part is adjusted by the precipitator, and then sodium bicarbonate or sodium hydroxide composite precipitation is adopted to recover the rare earth. The treatment method provided by the invention effectively solves the problems of high content of silicon, aluminum, sulfur and magnesium impurities and low total amount of rare earth in a rare earth enriched product when rare earth is recovered by a single precipitator, and poor crystallization, slow sedimentation, difficult filtration, high rare earth loss and the like of a rare earth carbonate product during traditional sodium bicarbonate precipitation, and realizes mining and smelting cyclic utilization of magnesium resources; and the overall development and utilization efficiency of the ionic rare earth ore is improved.

The invention discloses a steel cylinder cleaning method. The method comprises the steps that ethyl alcohol is injected into a steel cylinder; rolling the steel cylinder filled with the ethanol for multiple times to rinse the inner wall of the steel cylinder, and then emptying the ethanol in the steel cylinder; injecting ultrapure water into the steel cylinder cleaned by the ethanol; rolling the steel cylinder filled with the ultrapure water for multiple times, rinsing the inner wall of the steel cylinder, and then emptying the ultrapure water in the steel cylinder; nitric acid is injected into the steel cylinder cleaned by the ultrapure water, metal ions in the steel cylinder are dissolved, and then the nitric acid in the steel cylinder is emptied; injecting ultrapure water into the steel cylinder to rinse the steel cylinder, and emptying the ultrapure water in the steel cylinder; taking the discharged ultrapure water as a sample, and detecting the content of residual metal ions in the steel cylinder; according to the obtained metal ion content, whether the steel cylinder meets the cleanliness requirement or not is judged, if the cleanliness requirement is met, a small amount of nitric acid is added into the steel cylinder, sampling detection is conducted after the steel cylinder is moistened and washed, and if the test result is consistent with the previous metal ion content, the steel cylinder is clean. According to the steel cylinder cleaning method, external source introduction is avoided while metal ion impurities in the steel cylinder are treated.

The invention belongs to the technical field of geological sample analysis and detection, and particularly discloses a method for measuring the amount of each element of lithium ore in a closed acid-soluble system, and the method comprises the following steps: pretreating the lithium ore; the pretreated lithium ore is weighed and put into a closed sample dissolving device, hydrofluoric acid and purified nitric acid are sequentially added, and the closed sample dissolving device is closed; carrying out heat preservation on the closed sample dissolving device twice to obtain a test solution; and measuring the test solution by using an inductively coupled plasma mass spectrometer to obtain a working curve, and calculating the content of the analysis element in the sample solution by using the working curve. The method for determining the amount of each element in the lithium ore by adopting the closed acid-soluble system has the characteristics of simplicity in operation, high efficiency and good stability, realizes simultaneous determination of the amount of lithium, rubidium, cesium, beryllium, strontium, niobium, tantalum, zirconium, hafnium and rare earth elements in the large-batch lithium ore, and further provides a reference for determination of main trace elements in the lithium ore.

The invention provides a method for recovering scandium from scandium-containing lithium slag and a pretreatment method of the scandium-containing lithium slag. The method for recovering scandium from the scandium-containing lithium slag comprises the following steps: mixing the scandium-containing lithium slag with concentrated sulfuric acid, and heating and roasting to obtain a roasted product; the roasted product is subjected to water leaching, and scandium-containing leaching liquid and leaching residues are obtained; the scandium-containing leachate is extracted, and a scandium-containing organic phase and raffinate are obtained; washing the scandium-containing organic phase to obtain a purified scandium-containing organic phase and a washing solution; carrying out reverse extraction on the purified scandium-containing organic phase, and filtering to obtain a reverse extract; the reverse extract is subjected to acid dissolution, and a scandium-containing acid solution is obtained; adding oxalic acid into the scandium-containing acid solution for precipitation, filtering to obtain scandium oxalate precipitation, and roasting to obtain scandium oxide.

The invention discloses a preparation method of a modified red-mud-based chlorobenzene catalyst, which comprises the following steps: taking solid waste red mud as a main component, adding a certain amount of acid for dissolving, dropwise adding alkali liquor to enable the pH value of red mud suspension to reach 8-9, washing to be neutral, drying, grinding, passing through a molecular sieve, and roasting to obtain red-mud-based catalyst carrier powder; the red-mud-based catalyst carrier powder is mixed with a nitrate solution, it is guaranteed that the active component loading content in the mixed solution is 10-20%, and a filter cake loaded with the active component is roasted and then ground to obtain the red-mud-based catalyst. According to the method, the solid waste red mud is subjected to resource utilization, the red mud is modified into the efficient and low-cost catalyst to be applied to catalytic oxidation of volatile organic compounds, volatile organic compound waste gas is eliminated, the atmospheric environment quality is improved, waste is turned into wealth, and pollution is treated with waste.

The invention discloses a method for preparing iron phosphate through hydrogen-based micro-reduction roasting reinforced iron ore acid dissolution. The method comprises the following steps that (1) iron ore is pretreated into iron ore powder with D90 smaller than 74 micrometers; (2) hydrogen is introduced into the iron ore powder within the temperature range of 700-900 DEG C for micro-reduction roasting, the hydrogen flux of each kilogram of iron ore is 10-60 L / min, the roasting time is 5-30 min, and micro-reduction iron ore powder is obtained after cooling; (3) adding the micro-reduced iron ore powder into a mixed acid solution, adding a proper amount of a hydrogen peroxide solution, stirring and leaching at a set temperature to obtain a leaching mixed solution, and carrying out solid-liquid separation on the leaching mixed solution to obtain leaching residues and a leaching solution; (4) adjusting the pH value of the leachate, heating to a preset temperature, carrying out auxiliary stirring reaction, aging and filtering to obtain crude iron phosphate; and (5) calcining the crude iron phosphate, and cooling to obtain the battery-grade iron phosphate. By means of the method, the acid dissolution efficiency of the iron ore can be effectively improved, acid consumption and energy consumption are reduced, meanwhile, green production can be achieved, and the requirement for sustainable development is met.

The invention belongs to the technical field of waste resource treatment and recovery, and provides a hematite type waste residue treatment method which comprises the steps that hematite type waste residues are sequentially pulpified and washed, and washed residues are obtained; the washing slag is leached, and a leaching solution is obtained; mixing the leachate with iron powder and sulfur, and carrying out reduction reaction to obtain reduced liquid and reducing slag; mixing the reduced liquid with a precipitant, and carrying out an aluminum precipitation reaction to obtain a purified liquid and aluminum slag; and the purified liquid is electrolyzed, and the electrolytic iron powder is obtained. According to the method, the waste residues are subjected to acid dissolution through the hydrometallurgy technology and then are prepared into the electrolytic iron powder through the electrolysis technology, iron and impurities such as aluminum and silicon can be fully separated, a high-value iron powder product is obtained, meanwhile, the impurities can be further fully utilized, and by-products of nickel and aluminum are obtained.

The invention relates to a method for high-value utilization of waste lithium iron phosphate battery lithium extraction slag, and belongs to the technical field of waste lithium ion battery resource utilization. The method comprises the following steps: S1, mixing the lithium iron phosphate lithium extraction slag with a low-concentration sulfuric acid solution in proportion, carrying out countercurrent washing, carrying out solid-liquid separation, carrying out acid dissolution on a solid, carrying out gradient recycling on a washing solution, and carrying out resin adsorption and reverse osmosis treatment on a high-impurity washing solution for recycling; s2, reacting the pretreated solid with medium-concentration sulfuric acid, reducing a dissolved solution by using iron powder, then carrying out solid-liquid separation to obtain a first batch of ferrous sulfate heptahydrate, adding concentrated sulfuric acid into mother liquor, carrying out secondary crystallization, then carrying out solid-liquid separation, and recrystallizing the obtained solid by using washing wastewater to obtain a second batch of ferrous sulfate heptahydrate; s3, recovering sulfuric acid by adopting a membrane treatment method, and recovering phosphoric acid from residual mother liquor by adopting an extraction method; or directly treating the lithium iron phosphate waste residue. According to the method, efficient separation and recovery of iron and phosphorus resources and full-component high-value utilization of the lithium iron phosphate lithium extraction slag are realized.

The invention relates to the technical field of detection, and particularly provides a method for determining the quality and purity of silver in a silver-gold-plated product. The determination method comprises the following steps: dissolving a surface gold plating layer of a silver-plated product with aqua regia, and then dissolving a silver chloride protective film on the surface of silver with ammonia water, so that the problem that the mass of silver cannot be accurately weighed after the gold plating layer in the product is removed is solved, and the problem that the silver chloride protective film hinders the dissolution of pure silver with nitric acid to influence the determination is also solved. Thiourea is further adopted to dissolve a complex of diamine and silver, the situation that when silver is dissolved, added nitric acid reacts with the complex of diamine and silver to generate silver chloride precipitates is prevented, an ammonium nitrate solution is used for washing thiourea, a flame atomic absorption spectrometry method is adopted for conducting mass correction on silver in the solution obtained after aqua regia gold is dissolved, and the total silver mass is obtained through calculation. According to the determination method, the quality and the purity of the silver in the silver-plated product can be relatively accurately obtained.

The invention discloses a method and a system for adding a 3N electrolytic manganese metal additive. The method comprises the steps that S1, a manganese sulfate neutral solution is prepared, after manganese carbonate ore powder is subjected to acid dissolution, sodium dimethyl dithiocarbamate and a barium sulfide purifying agent are added to conduct impurity removal, purification and acid collection on the manganese sulfate solution, then air is introduced to remove iron, the manganese sulfate solution obtained after filter pressing is neutralized with ammonia water, the pH value of the solution is adjusted, and the qualified manganese sulfate electrolyte is prepared. According to the 3N electrolytic manganese metal additive adding method and system, an ammonium sulfite adding method is changed from adding in a manganese sulfate neutral liquid tank to dropwise adding an ammonium sulfite aqueous solution at a liquid inlet port of an electrolytic bath, and the concentration and the liquid inlet speed of the ammonium sulfite aqueous solution are controlled, so that the content of ammonium sulfite in the electrolytic bath is stable, and the condition of the electrolytic bath is stable; the addition amount of the additive is reduced, introduction of impurities is avoided, and meanwhile, oxidation-reduction reaction caused by too long retention time of ammonium sulfite in the liquid is reduced.

This invention discloses a method for resolving isomers of methylfenacin ester, comprising: firstly, dissolving methylfenacin ester in a first solvent and adding L-tartaric acid, dissolving until clear; then adjusting the system temperature to 40℃-53℃ and adding L-tartaric acid seed crystals of the target isomer; subsequently, cooling the system to 20℃-30℃, filtering the precipitated product, and obtaining the L-tartaric acid seed crystals of the target isomer as the filter cake; dissociating the L-tartaric acid seed crystals of the target isomer using an alkaline resin, collecting the filtrate, and drying the filtrate to obtain the target isomer of methylfenacin ester. This invention achieves the resolution of isomers of methylfenacin ester by using L-tartaric acid, and through optimization of conditions, achieves a yield of not less than 74.1% and an ee of 91.1% for the target isomer of methylfenacin ester. The resolution method provided by this invention is simple to operate, easy to control, suitable for large-scale production, and meets industrial needs.

The invention relates to a method for measuring and analyzing nickel, silicon and phosphorus in nickel-containing pig iron, in particular to the technical field of detection and analys.The measuring and analyzing method comprises the steps that a nickel-containing pig iron sample is drilled, sampled and separated through a hard alloy drill bit, and a test sample is obtained; sequentially carrying out acid dissolution, solid-liquid separation and constant volume on the obtained test sample to obtain a test solution; measuring the contents of nickel, silicon and phosphorus in the obtained test solution by adopting a full-spectrum direct-reading inductively coupled plasma emission spectrum; a standard curve used in the full-spectrum direct-reading inductively coupled plasma emission spectrum measurement is obtained by dissolving a gradient nickel-containing pig iron standard sample to a constant volume. According to the determination and analysis method provided by the invention, the detection process is designed, so that the nickel, silicon and phosphorus elements in the nickel-containing pig iron with the nickel content of 8-15% can be jointly determined, and a scientific data basis is provided for production management and control.

Provided herein are compositions and methods for removing a coating, such as an environmental barrier coating (EBC), from a substrate. By some approaches, a method for removing a coating from a substrate comprises contacting the coating with a salt, the salt being a solid. The method also involves heating the coating and the salt to a temperature at or above the melting point of the salt to convert the coating to a dissolvable reaction product by fusion of the coating with the salt. After forming the dissolvable reaction product, the product is then dissolved using an acid to remove at least a portion of the coating from the substrate.

The present invention provides a method for treating oily wastewater. The method relates to the field of oily wastewater treatment. A solid-oil-water slurry phase obtained by mixing a hydrophobic ZIF material with oily wastewater and allowing it to stand is placed in an acidic environment. The oil-containing hydrophobic ZIF material is dissolved with acid, and a ligand corresponding to the hydrophobic ZIF material is added to the aqueous phase after acid hydrolysis to recover the hydrophobic ZIF material and the oil. Through acid hydrolysis, the hydrophobic ZIF material is decomposed into its constituent components in an acidic environment, and oil substances can be completely released, avoiding the situation where oil substances remain on the solid material, thereby improving the oil recovery rate and recycling the hydrophobic ZIF material, reducing material consumption and waste generation.

The application provides a method for recovering valuable metals in waste lithium battery black powder based on a eutectic solvent, uses a green solvent system composed of a choline / guanidine compound A containing a quaternary ammonium salt structure and an organic carboxylic acid compound B containing two or more carboxyl groups to recover valuable metals in waste lithium battery black powder, realizes preliminary and efficient separation of lithium cobalt manganese and nickel and graphite, recovers cobalt, manganese and lithium from the leaching solution through a step-by-step precipitation method after the lithium cobalt manganese enters the leaching solution, recovers nickel and graphite through acid dissolution separation of the mixture containing nickel and graphite, separates and recovers the mixture of nickel and graphite through subsequent treatment, the leaching conditions are mild, the pollution is small, the cost is low, and the method has good social and economic benefits; the method provided by the application can produce a plurality of high-value products, has the advantages of strong adjustability, high precipitation efficiency, green environmental protection and low cost, and has wide application value in the separation and recovery of valuable metals and graphite resources in battery black powder.

The invention discloses a method for stabilizing treatment of chromium-containing sludge and recovery of magnetic ferrochrome oxide, which adopts a simple solvothermal process, uses ethylene glycol as a reducing solvent, prevents Cr (III) from being oxidized into Cr (VI) in the solvothermal process, and converts iron-chromium hydroxide in the treated chromium-containing sludge into magnetic iron-chromium oxide, so that the magnetic ferrochrome oxide is recovered. The residual calcium-containing phase in the original chromium-containing sludge can be removed through an acid dissolution method, and finally the magnetic iron-chromium oxide with the calcium content lower than 2% is obtained. After treatment, the chromium content in the ethylene glycol solvent is lower than 0.2 mg / L, the next batch of sludge treatment can be carried out, and meanwhile, the chromium content in the acidic calcium ion leachate is lower than 0.9 mg / L. The method is simple in process, low in requirement on industrial equipment and low in required energy consumption, and meanwhile, the product obtained through treatment can show certain application potential in the fields of environmental protection, high-end manufacturing and the like.

This invention discloses a method for preparing hollow metal sulfides based on a mild template method using calcium carbonate. Calcium chloride powder and potassium carbonate powder are uniformly dispersed separately in an alcohol solution. The two solutions are then mixed and allowed to stand for aging to obtain solution A. Simultaneously, thioacetamide is dissolved in the alcohol solution to obtain solution B, and a chloride is dissolved in the alcohol solution to obtain solution C. The chloride is either stannous chloride or copper chloride. Then, solutions B and C are added sequentially to solution A at a molar ratio of thioacetamide to chloride of 2:1 and mixed uniformly to obtain solution D. Solution D is then placed in a polytetrafluoroethylene (PTFE) reactor and reacted at 140–180°C for 12 hours. Carbon dioxide is then continuously bubbled through the reactor for 2–3 hours. The mixture is filtered and washed with water and ethanol to obtain the hollow metal sulfides. This invention can obtain hollow metal sulfides with different morphologies and avoids the contamination problems associated with high-temperature calcination or acid dissolution for template removal.

The invention discloses an aluminum oxide proppant and a preparation process thereof, and belongs to the technical field of ceramic fillers. The aluminum oxide proppant is prepared from the following raw materials in parts by mass: 55-72 parts of bauxite; 15 to 25 parts of calcined kaolin; 5 to 10 parts of potassium feldspar; 0.3 to 0.9 part of manganese dioxide; 0.1 to 0.4 part of titanium dioxide; 4-8 parts of a reinforcing agent; the reinforcing agent is formed by mixing co-fired zirconium-based premixed powder and carbonate. The preparation method comprises the following steps: performing conventional wet-process ball-milling to form slurry, performing spray granulation, rolling and forming, performing segmented firing and granulating. According to the scheme, a stable secondary phase is generated in situ between aluminum oxide frameworks in the sintering process, stable zirconium dispersion distribution is achieved, densification and grain boundary stabilization are achieved with low addition amount, the breakage rate under the specified pressure grade is reduced, the acid dissolution rate under the mixed acid condition is reduced, and the product granularity and sphericity are stable.

The invention discloses an armored sand-ceramsite bimodal proppant based on performance matching as well as a preparation method and application thereof, and relates to the technical field of oil and gas exploitation. The proppant comprises ceramsite and armored sand which are compounded according to the mass ratio of (20: 80)-(60: 40), the volume density ratio of the ceramsite to the armored sand is 0.9-1.1, the median particle size ratio of the ceramsite to the armored sand is 1.5-3.0, it can be ensured that the proppant is evenly and stably conveyed to a target crack, the ceramsite forms a bearing framework, gaps are filled with the armored sand, and a synergistic and stable composite supporting structure is constructed. According to the proppant, the four-in-one performance matching design of volume density, breakage rate, acid solubility and particle size is adopted, the obtained proppant is superior to a conventional proppant in breakage resistance, acid corrosion resistance and long-term flow guide performance, the preparation cost is low, the defects of performance mismatch, system failure and the like of the conventional proppant can be overcome, and the proppant has wide application prospects in hydraulic fracturing construction of oil and gas fields.

The application discloses a method for recovering and purifying chloroiridic acid from an iridium-containing waste catalyst, which comprises the following steps: firstly, mixing the iridium-containing waste catalyst with a reaction aid and a solid oxide, and then performing a melting reaction under the temperature condition of 250-400 DEG C to obtain an iridium oxide melt which is hardly soluble in water; secondly, adding water to the melt to remove impurities, and then filtering to obtain the iridium oxide; finally, adding acid to the iridium oxide to obtain a chloroiridic acid solution. The method for recovering and purifying chloroiridic acid from the iridium-containing waste catalyst can obtain the iridium oxide which is only soluble in acid but hardly soluble in water after the melting reaction under the temperature condition of 250-400 DEG C, and then the metal impurities and the catalyst carrier in the catalyst can be removed by simple water washing, and the chloroiridic acid can be obtained by acid leaching, so that the method is short in route, low in cost, and suitable for industrial application; in addition, the purity of the chloroiridic acid is high (more than 99.95%), and the recovery rate is also high (more than 98%).

The present invention relates to a method for preparing vitamin C. The method comprises: dissolving 2-keto-L-gulonic acid in water to obtain a keto-gulonic acid solution; adding a catalyst composed of palladium acetate, citric acid, and L-alanine to the keto-gulonic acid solution; reacting at 30-35 degrees Celsius for 1-2 hours; heating to 50-55 degrees Celsius; and after the reaction is carried out for 20 hours, stopping heating and unloading to obtain a solid liquid containing vitamin C; cooling the solid liquid containing vitamin C at room temperature for crystallization for 4-6 hours, and then using centrifugal separation and purification to obtain vitamin C. The process for preparing vitamin C using the scheme of the present invention is simpler and more efficient.

The invention relates to a process for preparing nylon 52 salt with low energy consumption, which comprises the following steps: dissolving oxalic acid in absolute ethyl alcohol to form an oxalic acid ethanol solution; the method comprises the following steps: slowly dripping pentamethylene diamine into an oxalic acid ethanol solution for reaction, and gradually separating out a nylon salt solid from the solution along with the proceeding of the reaction; and continuously stirring and fully reacting, carrying out solid-liquid separation by adopting a suction filtration mode, washing and drying to finally obtain a nylon salt solid. The process for preparing the nylon 52 salt is mild in reaction condition, especially can form salt at room temperature, and not only reduces energy consumption, but also can reduce by-product impurities possibly generated in high-temperature reaction due to the fact that high-temperature heating is avoided. Besides, inert gas protection is not needed in the whole salt forming process, the pH value of the reaction process does not need to be controlled, operation is easy and convenient to control, and the prepared nylon 52 salt has the advantages of being high in yield and purity.

The invention relates to a sample pretreatment method for chromite microelement analysis. The method comprises the following steps: firstly, treating a sample to specific particle size distribution (Dv (50) lt, 5 [mu] m, Dv (90) lt, 20 [mu] m) through physical accurate grinding, and then adopting an improved two-step acid dissolution and digestion process: firstly, destroying main crystal lattices of minerals by using mixed acid, then, carrying out targeted dissolution on a residual insoluble phase by using aqua regia, and finally, carrying out chlorine removal treatment to obtain a solution to be detected. Through the synergistic effect of physical accurate grinding and secondary acid dissolution, almost complete decomposition of chromite is achieved, especially the extraction efficiency of key indissolvable elements such as Sc and Zn is improved by 20% or above, the accuracy and precision of ICP-MS analysis results are remarkably improved, and the problem that microelement measured value systematicness is low due to incomplete dissolution in a traditional method is solved.

The utility model provides an acid dissolution experiment device, and relates to the technical field of experiment devices.The acid dissolution experiment device comprises at least two acid storage containers, a mixing container, at least two flow meters and at least two control valves, all the acid storage containers are arranged in parallel, the mixing container is provided with a mixing cavity, all the acid storage containers are communicated with the mixing cavity, and the flow meters are arranged in the mixing cavity; a flow meter is arranged on a communication path of each acid storage container and the mixing container, and a control valve is arranged on a communication path of each flow meter and the mixing container; according to the acid dissolution experiment device, the at least two acid storage containers and the flow meters and the control valves which are in one-to-one correspondence with the acid storage containers are arranged, so that the instantaneous flow rate and the total flow rate of the acid solution flowing into the mixing container from the acid storage containers can be controlled, and the technical problem of difficulty in simultaneously and quantitatively adding multiple acids in the acid dissolution experiment device is solved; the requirements of experiments on the acid solution are met, and the accuracy and reliability of experimental data are improved.

The invention provides a ternary iron-lithium fully-compatible integrated circulation treatment method and system application, and the method comprises the following steps: mixing lithium iron phosphate black powder and ternary material black powder, carrying out first acid leaching, carrying out primary copper removal on a first acid leaching solution, carrying out a mixed reaction on a copper-removed solution, an oxidizing agent and a crystal inhibition dispersant, and carrying out secondary acid leaching on a second acid leaching solution; first ferrophosphorus slag and dephosphorized liquid are obtained; the crystal inhibition dispersing agent comprises an organic phosphonic acid compound; performing iron and aluminum precipitation on the phosphorus-removed liquid to obtain iron and aluminum slag and iron and aluminum-removed liquid; the first ferrophosphorus slag and the iron-aluminum slag are subjected to alkali dissolution, second ferrophosphorus slag and aluminum-containing liquid are obtained, the second ferrophosphorus slag is subjected to acid dissolution, and ferrophosphorus liquid is obtained; and performing secondary copper removal on the iron and aluminum removed liquid to obtain a pre-extraction liquid and copper slag, and extracting the pre-extraction liquid to obtain a nickel salt solution, a cobalt salt solution and a lithium salt solution. Various wastes such as battery powder, pole piece powder, slurry and the like of the ternary lithium battery and the lithium iron phosphate battery can be fully compatible and integrally recycled.

The invention discloses a heavy metal emission reduction and sludge reduction treatment process method for circuit board wastewater. The invention provides a layered precipitation strategy of'first acid, second alkali and second sulfur '. The method comprises the following steps: performing acid precipitation on alkaline organic wastewater by using acidic wastewater, and recovering printing ink residues; carrying out air stripping treatment on the copper ammonia wastewater by utilizing an alkaline condition, and precipitating high-purity copper hydroxide; and finally, carrying out deep precipitation on residual complexing heavy metals by utilizing excessive sulfides in the pretreatment stage, and further recovering copper resources in the comprehensive water tank through coprecipitation of copper hydroxide and copper sulfide. Sludge generated in each process is classified and treated; printing ink slag, biochemical residual sludge and copper / nickel sulfide sludge are subjected to synergistic pyrogenic process treatment; copper hydroxide sludge is selectively subjected to acid dissolution to prepare copper sulfate. Lime, ferrous sulfate and polyaluminum are not used in the whole process. According to the method, the medicament is utilized to the maximum extent, the sludge is reduced by 50% or above, and the resource value of valuable metal is increased by 3-5 times.

The invention relates to a method for recovering tungsten from tungsten-containing calcium sulfate slag, which comprises the following steps: S1, soda boiling: taking the tungsten-containing calcium sulfate slag, adding water for size mixing, adding sodium carbonate or sodium bicarbonate into the obtained size, and carrying out solid-liquid separation after reaction to obtain a sodium tungstate solution and residues; s2, acid dissolution: taking the residues in S1, adding water for size mixing, and adding hydrochloric acid into the obtained size to obtain a tungstic acid solution; s3, enriching, namely recycling the sodium tungstate solution obtained in the step S1 as alkali boiled mixed slurry; recycling the tungstic acid solution obtained in the step S2 as acid-soluble slurry mixing liquid; the operation of S1 and S2 is repeated until the tungsten content of the solution reaches 100 g / l, and high-concentration sodium tungstate and tungstic acid are obtained; s4, adsorption; and S5, desorbing to obtain a sodium tungstate solution. The method can realize 100% recovery of tungsten in the tungsten-containing calcium sulfate slag, and has industrial application prospects.