30results about How to "Low content of impurity ions" patented technology

The invention provides a preparation method of a vanadyl sulfate crystal and application of the vanadyl sulfate crystal.The method comprises the following steps that vanadium pentoxide and sulfuric acid with the concentration of 15 mol / L-20 mol / L are added into a reaction kettle and mixed to be uniform; the reaction kettle containing vanadium pentoxide and sulfuric acid with the concentration of 15 mol / L-20 mol / L is put into a sealed reactor, reduction gas is introduced into the sealed reactor, the temperature is increased, and a reduction reaction is conducted; after the reduction reaction is completed, the reaction kettle is taken out, and the vanadyl sulfate crystal is obtained.The high-purity vanadyl sulfate crystal is prepared directly through a reduction method, evaporation crystallization treatment is not needed in the whole technology process, operation is easy, the reaction condition is mild, the cost is low, and the content of foreign ions in vanadyl sulfate electrolytes prepared from the high-purity vanadyl sulfate crystal is low and lower than 10 ppm.

The invention relates to a method for preparing waste recovered graphite powder into graphene. The method comprises the following steps of: mixing waste recovered graphite powder and concentrated sulfuric acid in a reaction kettle, stirring and uniformly mixing; slowly adding potassium permanganate; fully stirring and keeping a low temperature (20 DEG C); heating solution to 35+ / -5 DEG C and keeping the temperature for 30-90 minutes; slowly adding a certain amount of distilled water, heating the solution to 80-90 DEG C and keeping the temperature for 15-30 minutes; slowly adding hydrogen peroxide into the solution and slowly stirring to obtain golden yellow graphene oxide slurry; washing the slurry by using hydrochloric acid, potassium hydroxide and de-ionized water of certain concentration in sequence to remove impurity ions; and finally, holding an obtained graphene oxide sample in a high-temperature reaction furnace, and heating under an environment of argon, hydrogen or ammonia gas at 500-800 DEG C for 1-3 hours to reduce to obtain a graphene sample with thickness of 1-5 atom layers. The method has the advantages of low production cost, short period, high yield, simplicity and easiness for control of equipment and suitability for large-scale production. The waste recovered graphite powder is used as a carbon source, so that the utilization rate of an environment resource is effectively increased.

The invention belongs to the technical field of rare earth compound preparation, and particularly relates to a preparation method of cerium glue with high glue forming performance. According to the method, firstly, soluble cerium salt is prepared into a cerous nitrate or cerium chloride solution; hydrogen peroxide is used as an oxidizing agent; ammonium hydroxide is used as a precipitant; throughtransformation, cerium hydroxide precipitates are obtained; the cerium hydroxide precipitates are heated to the temperature of 85 to 100 DEG C; the state is maintained for 30 to 90 min; the materialsare washed until the electric conductivity is less than 5 ms / cm; plate frame press filtering is performed; cerium hydroxide paste is obtained; the cerium hydroxide paste and monobasic acid are pulpedinto glue; drying is performed to obtain a primary cerium glue product; the primary cerium glue product is dissolved into a solution with the cerium ion concentration being 0.2 to 0.6 mol / L through adding deionized water; then, ammonia water precipitation is performed; after the materials are washed until the electric conductivity is less than 5 ms / cm, plate frame press filtering is performed to obtain cerous hydroxide paste; monobasic acid is added for pulping to obtain glue; drying is performed to obtain a product. The dissolution degree of the prepared cerium glue product prepared by the invention can reach 350 g / L or higher (the content of rare earth oxide); the product can be applied to the production process requiring high-concentration tetravalent cerium solution.

The invention relates to a method for regenerating the spent electrolyte of an all-vanadium redox flow battery. Its technical scheme is: according to the mass ratio of carbon material: anion exchange resin: binder: organic solvent is 1: (0.1 ~ 1): (0.05 ~ 0.5): (2 ~ 10) batching, mixing, to obtain a mixed solution Ⅰ; according to the mass ratio of carbon material: cation exchange resin: binder: organic solvent is 1: (1-5): (0.05-0.5): (2-10) ingredients, mix evenly to obtain mixed liquid II. Spray or smear the mixed solution Ⅰ and mixed solution Ⅱ on the graphite felt electrodes respectively, and then dry them, then place the dried anode composite electrode and cathode composite electrode on the corresponding positive and negative terminals of the capacitive deionization device, Under the condition of DC voltage, the exhausted electrolyte solution of the all-vanadium redox flow battery is circulated and pumped into the capacitive deionization device to obtain the electrolyte solution Ⅰ. Add a chelating agent to the electrolyte I and mix to obtain a regenerated electrolyte. The regenerated electrolyte prepared by the invention has low impurity content and good stability and electrochemical performance.

Disclosed in the present invention are a hydroxyl silicone oil and a continuous method for preparing same. The continuous method for preparing the hydroxyl silicone oil includes following steps of: 1) adding hexamethyl cyclotrisiloxane, a solvent and water into a mixing kettle, stirring and mixing them evenly, and then transferring the mixture into a fluidized bed filled with a catalyst to react sufficiently; 2) carrying out an adsorption filtration and an ultrafiltration membrane filtration, removing low molecular weight compounds at normal pressure and removing low molecular weight compounds at a reduced pressure so as to obtain the hydroxyl silicone oil, recovering the solvent and unreacted low molecular weight compounds, detecting the content of each component and then recycling them. The method of the present invention has high efficiency and low energy consumption, being free of pollutant emission, being clean and environmentally friendly, and having low production cost. The solvent used in the reaction and the unreacted low molecular weight compounds can be entered into a reaction system to be recycled after the content of each component is detected, such that the method is free of pollutant emission, being green and environmentally friendly. The hydroxyl silicone oil of the present invention has low viscosity, high product purity, low content of rings, low content of impurities and high storage stability.

The invention discloses a method for enhancing the quality of industrial sodium hexametaphosphate. The method comprises the following steps of: dissolving the industrial sodium hexametaphosphate as a raw material into high-purity water; carrying out secondary filtration, and then keeping constant temperature through a heat exchanger; separating through a reverse osmosis device; reducing the content of impurity ions to obtain a sodium hexametaphosphate product with the quality enhanced. Compared with the prior art, the method can be used for preparing the sodium hexametaphosphate product with the quality enhanced and the total phosphate content (in terms of P2O5) more than 68.5%, and effectively reducing the content of water-insoluble substances and the foreign ions, such as Fe and F, in the sodium hexametaphosphate product which is superior to the quality standard of GB1890-2005. The method for enhancing the quality of the industrial sodium hexametaphosphate, which is disclosed by the invention, has the advantages of safety, easiness and convenience for operation, stable product quality and suitability for industrial production.

The invention relates to high-purity iron phosphate used for producing a lithium ion battery positive-pole material and a preparation method thereof. The preparation method is characterized by comprising the following steps: taking ferrous salt and carbonate as raw materials; reacting to generate intermediate product ferrous carbonate precipitation, wherein, the ferrous carbonate is easy to filter, and the foreign ions are easy to wash; filtering and recovering ammonium sulfate; dissolving the ferrous carbonate precipitation; adding oxidant for oxidizing; regulating the pH value of the solution; heating and preserving the temperature for a certain time to obtain the iron phosphate precipitation; filtering, drying and precipitating to obtain the high-purity iron phosphate; and mixing and calcining the high-purity iron phosphate, the lithium source and the carbon source to obtain the lithium ion battery positive-pole material with excellent electrochemistrical performance. By using the method provided by the invention, the impurity content in the iron phosphate is effectively lowered, the process time is shortened, the energy consumption is reduced, and the cost and the consumption of the raw materials are lowered; and the filter liquor is easy to recover, and the production cost is very low, thus being beneficial for large-scale production in scaled industry.

The invention belongs to the technical field of preparing salt from seawater, and relates to a process for producing high-purity refined salt by utilizing selective electrodialysis concentration of brine. The method comprises the following steps: a potassium removal process: concretely a potassium-rich solution and potassium-poor seawater are obtained after potassium ion adsorption and elution arecarried out on seawater by using a potassium removal system, the pH value of the potassium-rich seawater is regulated, and then the potassium-rich seawater is taken as electrodialysis inflow water; an electrodialysis concentration process: concretely concentration treatment is carried out on the electrodialysis inflow water by adopting a monovalent selective ion exchange membrane, the electrodialysis water inlet water is treated by the using an electrodialysis concentration process, and then desalted seawater and concentrated brine are obtained; and a crystallization process: concretely evaporative crystallization treatment is carried out on the concentrated brine obtained in the electrodialysis concentration process, and then the high-purity refined salt is obtained. Through the adoptionof the method disclosed by the invention, a raw material for preparing potassium chloride can be obtained, and potassium ions in a raw material liquid can also be removed, so that the problem of poorselectivity of electrodialysis concentration on sodium ions and potassium ions is effectively solved, the quality of brine and refined salt is further improved, and the high-purity refined salt is obtained.

The invention belongs to the field of preparation of phosphomolybdate and relates to a preparation method of zinc phosphomolybdate containing a keggin structure. The preparation method adopts a liquid-phase method to synthesize the zinc phosphomolybdate and comprises the following steps of: adopting phosphomolybdic acid and zinc oxide as raw materials, adopting distilled water or alcohol as a solvent, controlling PH to be 1.0-3.0, and reacting under a water-bathing condition with the temperature of 55-65 DEG C; carrying out reduced-pressure distillation to obtain pasty substance, and drying for 8-10 hours at the temperature of 70-90 DEG C to obtain orange zinc phosphomolybdate. The preparation method has the beneficial effects that the process is simple, the reactant raw materials are cheap in price, the impurity-ion content is low, the yield is high and the benefit for reducing the production cost is achieved; the prepared zinc phosphomolybdate containing the keggin structure can meetthe requirements of application in the aspects of catalyst synthesis, pharmaceutical synthesis, electrochemical application and flame-retardant compounding and the like.

The invention provides a method for preparing battery-grade nickel salt, which relates to the technical field of batteries, and comprises the following steps: adding water and inorganic acid to a reaction vessel to form an acid solution; heating the acid solution to 90-110°C, and adding nickel powder Carry out the reaction, add nickel powder in the reaction process to maintain the nickel powder concentration and liquid-solid ratio of the reaction system, react for 14-20h, when the pH value of the solution is 3-5, the reaction ends, and the nickel salt solution is obtained; wherein, the acid solution The liquid-solid ratio with nickel powder is 4-6:1ml / g, and the amount of nickel powder added is 1.8-2.2 times of the theoretical consumption of nickel powder in the amount of inorganic acid; there is no baffle in the reaction vessel. The present invention optimizes the reaction conditions such as liquid-solid ratio, temperature, and nickel powder amount, and does not set baffles, so that the reaction rate is greatly increased, and the requirements can be met without adding hydrogen peroxide. The cost is low, green and safe, and the obtained nickel salt product is of high quality. , low impurity content.

The invention discloses a flocculating agent composition for preparing a ray emulsion and a desalination and concentration method. By widening the concentration ratio range of a primary mature emulsion, the flocculating agent composition meets the requirements of different-purpose films on the preparation of the ray emulsion. The flocculating agent composition consists of at least two polymers which accord with the requirement, or at least two polymers which are the same type according with the requirement and have different degrees of polymerization. The flocculating agent composition can perform flocculation (or precipitation) in an acid medium so as to desalt and concentrate the emulsion. Due to the silver halide emulsion high-efficiency desalination and concentration technology, the desalination and concentration method effectively reduces the content of impurity ions in the emulsion, reduces the bulk temperature for coating and drying, and improves the performance for preserving the film photographic properties.

The invention relates to the technical field of positive electrode materials for lithium batteries, and provides a method for preparing high-purity manganese sulfate. Firstly, heavy metal ions in a crude manganese salt solution are removed, and then the obtained liquid phase product is mixed with bicarbonate for calcium, magnesium, and manganese ionization. Precipitate to obtain crude manganese carbonate solid; then disperse the crude manganese carbonate solid in water and pass carbon dioxide into the dispersion to obtain refined manganese carbonate solid; dissolve the refined manganese carbonate solid in dilute sulfuric acid and concentrate and crystallize to obtain high-purity sulfuric acid manganese. The present invention converts the manganese salt into manganese carbonate by controlling the reaction conditions, and converts the calcium carbonate and magnesium carbonate accompanied by manganese carbonate precipitation into soluble bicarbonate by introducing carbon dioxide, thereby realizing the removal of calcium and magnesium ions, and then returning Dissolution and crystallization can easily obtain high-purity manganese sulfate. The method provided by the invention has simple steps and low cost, and the content of impurity ions in the obtained high-purity manganese sulfate is extremely low.