51results about How to "Less impurity ions" patented technology

The present invention relates to preparation process of magnesium compound, and is especially preparation process of magnesia for silicon steel. The present invention produces silicon steel level magnesia through a bittern-sodium carbonate process, which includes reaction of refined magnesium chloride solution and refined sodium carbonate solution at 65-85 deg.c for 5-15 min to produce basic magnesium carbonate, curing, filtering and calcining at 1100+/-50 deg.c for 2.0+/-0.5 hr. Thus produced silicon steel level magnesia has high purity, small average grain size, good coating performance, high adhesivity and other features, and the preparation process is simple and low in cost.

The invention discloses a method for recovering zinc in waste residue containing zinc ferrite through ferric sulfate roasting-water leaching. The waste residue containing zinc ferrite is mixed with a certain amount of ferric sulfate and then obtained mixture is roasted, so that the zinc ferrite is effectively decomposed and converted into zinc sulfate and ferric oxide; at the same time, little zinc, existing in the form of other substances such as zinc oxide, zinc sulfate and zinc silicate, in the waste residue can be converted into zinc sulfate under the condition, and is leached in a following washing process; the ferric oxide enters into leached slag, thus realizing zinc and iron separation; leachate, which is a zinc sulfate solution containing few impurity irons, can be directly returned to a hydrometallurgical process to recover zinc. The process disclosed by the invention is simple, environmental friendly and energy-saving, and the process effectively solves problems that a conventional wet hydrometallurgical process which is difficultly used to separate zinc and iron, is not high in zinc recovery rate, serious in environmental pollution and the like.

The invention relates to a method for producing water-soluble potassium ammonium phosphate from wet-process phosphoric acid. According to the method, a monoammonium phosphate solution is prepared from low-cost wet-process phosphoric acid as the raw material by the steps of desulfuration and defluorination and neutralization with ammonia; then the replacement reaction of the monoammonium phosphate solution and potassium chloride and the crystallization are carried out to obtain a water-soluble fertilizer which contains potassium dihydrogen phosphate as a main component and adopts ammonium dihydrogen phosphate as an auxiliary component, wherein the content of chlorine is smaller than 2%; and excess potassium chloride and nitrogen produce a by-product such as nitrogen phosphorus and potassium chloride water soluble compound fertilizer. Meanwhile, the by-product in the production process can be directly used as a citric acid soluble phosphatic fertilizer. The method has simple processes, and the prepared water-soluble ammonium potassium dihydrogen phosphate is high in purity, nutrient and potassium content. No waste residues are discharged in the whole process, so that the method is environment-friendly and has better social and economical benefits.

The invention discloses a method for preparing iron p-toluenesulfonate and a solution thereof. The method for preparing the iron p-toluenesulfonate includes the steps that (1) a sodium hydroxide solution and an ammonium ferric sulfate solution are prepared; (2) the sodium hydroxide solution is added in the ammonium ferric sulfate solution, the final potential of hydrogen (pH) value of reaction is 7.0 to 9.0, and iron hydroxide precipitation is obtained; (3) the iron hydroxide precipitation is washed, placed in a filter bag and suspended to be dried at room temperature until the iron hydroxide precipitation which is colloid and contains a small amount of water is formed; (4) iron hydroxide which is suspended to be dried is reacted with a p-toluene sulfonic acid to generate an iron p-toluenesulfonate solution; (5) the iron p-toluenesulfonate solution is filtered and concentrated to be viscous, and discharging-cooling and crystallization are performed; and (6) crystals are crushed and dried to obtain the product. The method for preparing the iron p-toluenesulfonate and the solution thereof has the advantages that the activity of the reaction intermediate iron hydroxide is good, the reaction with the p-toluene sulfonic acid is complete, the process is simple, the energy consumption and the cost are low, and the environmental pollution is small.

The invention relates to a method for co-production of industrial grade ammonium dihydrogen phosphate and feed grade calcium phosphate by using defluorinated phosphoric acid, belonging to the technical field of chemical industry production. The invention aims at solving a technical problem of providing a method for co-production of industrial grade ammonium dihydrogen phosphate and feed grade calcium phosphate by using defluorinated phosphoric acid. The method comprises the following steps: neutralizing the defluorinated phosphoric acid and a primary neutralizer, performing solid-liquid separation to obtain a filtrate A and a filter cake A, neutralizing the filtrate A and a secondary neutralizer to make pH of reaction liquid reach 3.0-5.0, and performing solid-liquid separation to obtain a filtrate B and a filter cake B; concentrating, crystallizing, filtering and drying the filtrate B; or directly performing spray drying at 60-200 DEG C on the filtrate B to obtain the industrial grade ammonium dihydrogen phosphate; and drying the filter cake A and the filter cake B in combination to obtain the feed grade calcium phosphate. According to the method provided by the invention, the technology is simple, generation of waste residue is avoided, raw materials are fully used, and purity of the produced products is high, so that the method has better social benefit and economic benefit.

The invention discloses a method for preparing an electronic-grade high-purity stannous methanesulfonate solution. The method comprises the following steps: (1) placing methanesulfonic acid and stannous oxide with the molar ratio thereof being 3:1-6:1 in a container, and heating up to 100-130 DEG C, reacting for 4-6h while stirring until the stannous oxide completely dissolves, so as to obtain a reaction liquid; (2) crystallizing the reaction liquid by cooling, filtering to obtain a filter cake, and washing and vacuum-drying the filter cake to obtain white stannous methanesulfonate crystals; and (3) adding stannous methanesulfonate to de-ionized water to obtain the stannous methanesulfonate solution. The method provided by the invention for preparing the electronic-grade high-purity stannous methanesulfonate solution has fewer impurity ions; containing only stannous methanesulfonate and water, the prepared product can be easily separated, thereby ensuring the high purity of stannous methanesulfonate solids; and the invention has the advantages of simple process, low cost and less environmental pollution.

The invention discloses an aqueous metal anti-rust agent containing cyclohexylamine citrate. The aqueous metal anti-rust agent has good anti-rust effects on iron, steel, iron alloys, aluminum, copper and the like, and thus can be utilized for rust protection of metal equipment and parts, wherein the metal equipment and parts are made of iron, steel, iron alloys, aluminum, copper and the like.

The invention discloses a preparation method of silicon-steel-level magnesium oxide coating especially for oriented silicon steel plates. The preparation method comprises selecting natural aphanitic magnesite to produce lightly-calcined magnesia powder; digesting the lightly-calcined magnesia, performing acid-base neutralization to remove calcium, reacting for 5-15 minutes at 15-30 DEG C to generate magnesium hydroxide, washing with water, filtering, drying, calcining for 2.0 +/- 0.5 hours under a temperature of 1100 +/- 50 DEG C to obtain the high-purity lightly-calcined magnesia powder; and processing the powder into desired micron-level particle sizes by using a jet mill. The silicon-steel-level magnesium oxide coating provided by the invention has characteristics of high chemical purity, low impurity ions, good suspension, low hydration rate, and good coating and adhesion, has physical properties far better than those of similar products, is a good annealing isolation agent for producing the oriented silicon steel plates and also simple in production operation, and can greatly reduce production cost.

The invention belongs to the technical field of electrochemistry, and relates to an internally circulating electrolysis type ozone generation device. A cavity is formed in the lower portion of a cathode water tank, the interior of the cavity is used as a cathode chamber for reacting, and a circulating channel with raw material water is formed between the cavity and the cathode water tank, so thatthe cavity and the cathode water tank form an integrated cathode reaction assembly. In the same way, a cavity is formed in the lower portion of an anode water tank, the interior of the cavity is usedas an anode chamber for reacting, and a circulating channel with raw material water is formed between the cavity and the anode water tank, so that the cavity and the anode water tank form an integrated anode reaction assembly. An ion exchange resin column is arranged on the upper portion of the anode water tank component. The device is convenient to assemble, compact in structure and good in heatdissipation effect, the ozone concentration is high, and running is stable.

The invention relates to a method for synthesizing a nanoscale lithium iron phosphate positive electrode material, and specifically relates to a method for synthesizing a lithium iron phosphate material in a liquid phase by using synthetic iron hydroxide as a reactant. The method can reduce impurity ions in the material and reduce particle size. Besides, the performance of the material is comprehensively increased by introducing liquid phase C coating.

This invention discloses a method for preparing stannous sulfamate solution and an application thereof. The method comprises the following steps of: (1) taking stannous oxide, and adding pure water for rinsing; (2) mixing sulfamic acid and cleaned stannous oxide, and adding pure water, reducing agent and tartaric acid; heating the mixture to 60-90 DEG C, agitating and reacting for 2-4 hours to obtain solution A; (3) adding active carbon to the solution A, absorbing for 0.5-1.5 hours before filtering, and taking filtrate; (4) testing the content of stannous sulfamate in the filtrate and addingpure water to prepare the tin sulfamate solution with the needed concentration. The stannous sulfamate solution prepared by the method is high in purity and less in impurity ions; the preparation method provided by the invention has the advantages of simple process, less energy consumption, low cost and small pollution on the environment; and the method overcomes the disadvantages of the traditional method as follows: the operation cycle is long, the impurity ions are many and are difficult to treat, and the environment is polluted.

The invention discloses a method for recovering and purifying struvite from livestock and poultry manure, and the method comprises the following steps: putting the livestock and poultry manure into acontinuous flow reactor, and carrying out anaerobic fermentation to obtain manure digestive juice; introducing the manure digestive juice into an electrolytic reaction stirring tan, selecting magnesium as an anode of an electrode and selecting magnesium or metal of which the activity is lower than that of magnesium as a cathode, and electrolyzing under the stirring condition of a stirrer by usinga direct-current voltage; introducing the solution after the electrolytic reaction into a sedimentation tank for static sedimentation; introducing lower turbid liquid obtained after precipitation intoa heater; filtering the heated hot solution by using a filter film; and injecting clear liquid obtained after filtration of the filter film into a condensation recovery pool, and recovering the struvite solids. The method disclosed by the invention is low in cost, short in flow, simple to control, high in production efficiency, capable of separating the struvite from impurities, and suitable forindustrial popularization.

The invention discloses a method for preparing large-particle lithium carbonate from salt lake lithium-rich brine. The method comprises the following steps: step 1, heating the salt lake lithium-richbrine to 70-85 DEG C, after heating is completed, maintaining the temperature and adding a surfactant into the salt lake lithium-rich brine; step 2, maintaining the temperature in the step 1, adding acarbonate solution into the pre-treated salt lake lithium-rich brine, and performing a reaction for 1-3 h to obtain reaction product slurry; and step 3, allowing the reaction product slurry to standfor 10-20 h, performing solid-liquid separation, washing the obtained solid particles, and performing drying to obtain the large-particle lithium carbonate. According to the method provided by the invention, the certain surfactant is added into the reaction system, so that a particle size of the lithium carbonate is increased in the precipitation process, and the obtained lithium carbonate has a particle size d(0.9) of 300-600 [mu]m; and meanwhile impurity ions adsorbed at the surface of the lithium carbonate product are reduced, and purity and a yield of a primary product are improved, wherein the purity of the primary product is >=95%.

The invention discloses a low-cost extrusion casting process for an aluminum-titanium-boron refiner. The low-cost extrusion casting process comprises the following steps of step 1, preparing a melt; step 2, removing impurities from the melt; step 3, casting the melt; step 4, mold assembly and extrusion; step 5: opening mold and taking a part; and step 6, inspecting and warehousing. In the first step, titanium salt is potassium fluotitanate, boron salt is potassium fluoborate, and the temperature of molten aluminum is 800 DEG C. Compared with an existing manufacturing process of an aluminum-titanium-boron refiner, multiple impurity removal procedures are designed, impurity ions of alloy melt can be effectively reduced, the purity of the aluminum-titanium-boron refiner can be improved, and compared with an existing casting process, an aluminum-titanium-boron refiner casting is produced through the extrusion casting process, the alloy melt can be rapidly solidified under the high pressure, uniform distribution of active property points in the refiner is achieved, aggregation and clustering are avoided, the yield of the method is high, automatic production is convenient to achieve, and the labor cost is reduced.

The invention belongs to the technical field of mineral processing and particularly relates to a method for recovering vanadium by virtue of magnesiation and roasting of stone coal. The technical scheme is as follows: decarburizing stone coal ores, then adding MgSO4, performing fine grinding until the granularity is not greater than 100 meshes, performing fluosolid roasting, and performing water leaching on the roasted sample at a certain temperature, thereby obtaining vanadium-containing leachate; leaching the water leaching dregs with sulphuric acid, washing the leaching dregs with water, mixing acid leaching liquor with a washing solution so as to obtain a mixture used for leaching roasting dregs during water leaching, drying washed residues, mixing the dried washed residues with the decarburized stone coal ore, and performing ore grinding; and performing extraction and impurity removal on the obtained vanadium-containing leachate, then adding an NH4Cl solution for molybdenum precipitation, and incinerating the precipitate to obtain V2O5. The method is used for processing stone coal vanadium ore with vanadium content of no less than 0.80%; the recovery rate of vanadium in the obtained leachate is no less than 75%. According to the method, less harmful gases are discharged in a roasting process, the water consumption and the acid consumption are less, the production cost is low, solids and liquids can be recycled, and the application potential is great, so that the method is an economical and effective vanadium recovery method.

The invention provides a method for purifying tetrapropylammonium hydroxide based on diffusion dialysis. The method is characterized in that a diffusion dialysis device is used for purification; the diffusion dialysis device comprises an alkali chamber, a water chamber and an anion exchange membrane arranged between the alkali chamber and the water chamber; a tetrapropylammonium hydroxide solutionis added into the alkali chamber, and water is added into the water chamber, wherein the volumes of the tetrapropylammonium hydroxide solution and the water are identical; and static treatment in thediffusion dialysis device is performed for 80 to 110 h so as to complete purification. The purification method of the invention can effectively reduce impurity ions in tetrapropylammonium hydroxide,especially bromide ions; purification operation is simplified, and no manual intervention is needed in the process of purification, so the convenience of related operations is significantly improved;in addition, since the tetrapropylammonium hydroxide is purified by dynamic diffusion dialysis in the purification process, other chemicals are not involved, so no related waste materials are produced.