49results about "Vanadium compounds preparation" patented technology

The invention relates to a method for producing vanadium oxide by utilizing ion exchange to realize wastewater circulation and belongs to the field of the extraction of the vanadium oxide. The technical problem which is solved by the invention is to provide a method for producing the vanadium oxide, in which a high-quality vanadium product can be obtained and the problems that vanadium extraction wastewater reaches the emission standard and is recycled are thoroughly solved. The method for producing the vanadium oxide comprises the following steps: the vanadium oxide is prepared by the steps of the preparation of raw materials, calcification and roasting, infiltration, solid-liquid separation, ion exchange and impurity removal, vanadium precipitation, calcination and deamination or deoxidation and other steps; and the vanadium extraction wastewater is subjected to neutralizing treatment by using lime cream and returns a system for recycling, thereby realizing the zero emission of the wastewater. The method also improves the reclaiming rate of vanadium which is higher than that of the current process, and reduces production cost. The method is combined with other technologies to convert residue and other wastes after vanadium extraction into secondary resource for reutilization, thereby realizing clean production.

The invention discloses a method for extraction of failure vanadium from a waste SCR catalyst and preparation of activated titanium silicon tungsten powder for making a new denitration catalyst. The method includes: conducting pretreatment on a waste SCR catalyst, performing wet grinding to obtain a slurry, and adding an oxalic acid solution to carry out leaching reaction; carrying out filter-press separation to obtain tungsten silicon-containing titanium slag powder and press filtrate, then performing cleaning, activation, and fine grinding to obtain nanoscale titanium silicon tungsten powder; separating the press filtrate, recovering oxalic acid and returning the recovered oxalic acid to leaching reaction, adding an oxidizing agent into the separated liquid to carry out precipitation reaction so as to obtain ammonium metavanadate precipitate, and conducting filtering and separation to obtain ammonium metavanadate solid. The method provided by the invention uses oxalic acid for reaction under a normal temperature condition, can separate failure vanadium salt from the SCR catalyst, utilizes acid to activate other components and then performs fine grinding and other treatments so as to obtain the raw material for preparation of a new denitration catalyst. The process provided by the invention has the characteristics of low technological investment requirement and low energy consumption, effectively solves the harmless treatment problem of the SCR catalyst, and realizes recycling of resources.

The invention relates to a process for reclaiming a honeycomb SCR waste catalyst. The process comprises the following steps: grinding a waste catalyst, adding water to wash dust and impurities, drying and grinding, leaching under pressure at a high temperature, separating solid and liquid to obtain filter residues and an extraction solution, mixing the filter residues with hydrochloric acid and water, and calcining after the reaction to prepare rutile titanium dioxide; regulating the pH of the filtrate, and carrying out ion exchange and resolving to obtain a mixed solution with high content of ammonium paratungstate and ammonium metavanadate; regulating the pH of the mixed solution, adding ammonium salt, regulating the temperature, precipitating and crystallizing to obtain ammonium metavanadate crystal, separating solid and liquid, and evaporating and crystallizing the filtrate to obtain ammonium paratungstate crystal. The process adopts the ion exchange method to replace an extraction method and is easy to operate; the prepared product has high quality and high reclaiming rate, does not need high temperature or pressure, and is low in energy consumption and low in cost; tungsten, titanium and vanadium in waste catalyst can be effectively reclaimed, wastewater can be recycled or discharged up to standard, and the environmental risk is small.

The invention belongs to the field of wet-process metallurgy and particularly relates to a method for preparing vanadyl sulfate by use of a vanadium-containing chloride solution. The method comprises the following steps: 1) heating and reducing the vanadium-containing chloride solution, thereby obtaining a reduction solution; 2) regulating the pH value of the reduction solution to 0-2; 3), performing extraction, thereby obtaining a vanadium-loaded organic phase; 4) performing reverse extraction, thereby obtaining a vanadium solution; 5) regulating the pH value of the vanadium solution to 1-3; 6) extracting the solution, thereby obtaining the vanadium-loaded organic phase; 7) performing reverse extraction, thereby obtaining a vanadyl sulfate solution; and 8) absorbing the vanadyl sulfate solution by use of an adsorbent, thereby obtaining a vanadyl sulfate solution final product. According to the method, HCl leaching liquid containing vanadium resources, such as titaniferous magnetite and an SCR dead catalyst are utilized as raw materials, and an extraction-reverse extraction-deep impurity removal method is adopted, so that the method provided by the invention is capable of directly preparing high-purity anadyl sulfate from the vanadium-containing chloride solution, and has the advantages of short process and low cost.

The invention provides a preparation method of high-purity vanadyl sulfate. The method comprises the following steps: selecting a strong alkali solution for dissolving vanadium salts or vanadium compounds, removing impurities, filtering and adjusting a pH value of the solution to 1.5-5.0, then adding high-reducibility sulfuric acid compounds and phosphate diester precipitation preventing agents to obtain a tetravalent vanadium compound solution; enabling an alum solution and the tetravalent vanadium compound solution to fully react and generate water-insoluble tetravalent vanadium compound solid powder; washing the tetravalent vanadium compound solid powder with deionized water or distilled water, then carrying out solid-liquid separation; drying and firing the washed tetravalent vanadium compound solid powder, and then dissolving the tetravalent vanadium compound solid powder in a dilute sulfuric acid solution to obtain a water-soluble high-purity vanadyl sulfate solution. The method is capable of effectively removing various impurities in the vanadium salts or the vanadium compounds, fully reducing pentavalent vanadium compounds to tetravalent vanadium compounds and obtaining the high-purity vanadyl sulfate solution; the method is high in utilization rate of vanadium, short in technological process, low in cost and free of by-products; the large-scale production is easy to implement.

The present invention relates to a vanadium pentoxide preparation method, and provides a method for preparing vanadium pentoxide through composite extraction. The method comprises: (1) leaching; (2) reducing; (3) extracting, wherein a vanadium-containing material liquid is extracted with a composite extractant prepared from a phosphate organic matter and a modifier to prepare a vanadium-containing supported organic phase; (4) carrying out back extraction, wherein the supported organic phase is subjected to back extraction with sulfuric acid or a vanadium-containing sulfuric acid solution to prepare a vanadium-rich liquid; (5) removing acid, wherein the excess acid in the vanadium-rich liquid is extracted; (6) precipitating vanadium; and (7) calcining. According to the present invention, the vanadium is extracted with the composite extractant having strong extraction ability and strong back extraction ability, such that the vanadium extraction rate and the vanadium purity can be improved so as to improve the yield and the product of the vanadium pentoxide product, and the alkali consumption can be reduced so as to reduce the production cost.

The invention discloses a method for preparing high-purity ammonium metavanadate from a spent catalyst, which comprises the following steps: dephosphorization: collecting a spent catalyst leach solution in a leaching mode, filtering the leach solution, sending into an ion-exchange dephosphorization system, and carrying out phosphorus adsorption on the spent catalyst leach solution by using a resin; molybdenum-vanadium separation: sending the dephosphorized molybdenum/vanadium-containing solution into an ion-exchange system, and carrying out molybdenum adsorption by using a resin to separate the molybdenum and vanadium; and vanadium precipitation: pumping the vanadium-containing mother solution subjected to dephosphorization and separation molybdenum into a vanadium precipitation tank, and precipitating vanadium by using a weakly alkaline ammonium salt to obtain the high-purity ammonium metavanadate product. The method has the characteristics of short process, simple technique, energy saving, environmental protection, high efficiency, low cost and the like.

The invention belongs to the field of non-ferrous metal recovery, and particularly relates to a recovery method of a waste SCR denitration catalyst. The recovery method comprises the steps of pretreatment, TiO2 separation, extraction and purification, titanium recovery, vanadium recovery, tungsten/molybdenum recovery and the like. The recovery method is capable of recycling a several precious recovery products such as V2O5, ammonium tungstate/ammonium molybdate and BaTiO3 from the waste SCR denitration catalyst. The invention provides an effective technical scheme, and efficient resource utilization of the waste SCR denitration catalyst can be realized.

The invention provides a system for extracting vanadium from leachate containing vanadium, chromium and silicon and preparing vanadium pentoxide, and a treatment method thereof. The system sequentially comprises an impurity removal system, an extraction system, a stripping vanadium precipitation system, a washing system and a calcination system. The system and the method are characterized in thatdetailed studying of silicon, aluminum, chromium and other elements easily precipitating in the vanadium pentoxide product is carried out, different polymer forms of vanadium, chromium, silicon, aluminum and other impurities in an extraction feeding liquid, an impurity removal solution and raffinate are quantitatively detected through chemical regulation and device enhancement, and the structure of a extracted complex is detected, so the extraction mechanism of the vanadium, chromium, silicon and aluminum is scientifically predicated based on the result of quantitative experiment test studying; and the system is formed through chemical regulation impurity removal, an enhanced centrifugal extraction equipment and stripping quantification control and other measures in order to realize the preparation of low-chromium, low-silicon, low-aluminum and high-purity vanadium pentoxide product.

The present invention relates to a two-stage leaching process using concentrated hydrochloric acid that upgrades a variety of inferior quality titanium-iron ores into premium titanium concentrate and iron oxide products. The ground ore is leached with two separate quantities of hydrochloric acid after which the dissolved titanium is precipitated from the filtered liquor by hydrolysis. The still soluble iron chlorides are then optionally subjected to oxyhydrolysis to recover iron oxide and HCl. The process was developed for low-grade ores (under 12% TiO₂), and can be naturally applied advantageously to higher grade titanium-bearing ores.

The invention relates to a method for preparing high-purity ammonium polyvanadate. The method comprises the following steps: adding ferrous sulfate to a vanadium-containing solution, and performing stirring for a reaction; adding a silicon precipitating agent after the reaction is completed, performing stirring for a reaction, and carrying out solid-liquid separation; primarily adsorbing a solution obtained after the solid-liquid separation by using aminophosphoric acid resin; secondarily adsorbing the solution by using iminodiacetic acid chelated resin after the primary adsorption is completed; and adding ammonium sulfate to the secondarily adsorbed solution to precipitate vanadium, and performing solid-liquid separation to obtain the ammonium polyvanadate product. The method removes chromium, iron, magnesium, aluminum, silicon and other impurity elements in the vanadium-containing solution through process improvement and reagent control, and allows the ammonium polyvanadate product with a purity of above 99.9% to be obtained; and the high-purity ammonium polyvanadate product can be used to prepare other high-purity vanadium products, and has a good application prospect when applied to fields of metallurgy, aerospace, chemistry, batteries, pigments, glass, optics, medicines and the like.

The invention discloses a comprehensive utilization method of waste acids of the titanium dioxide industry, relates to a method of comprehensively utilizing and recovering waste acids of the titanium dioxide industry and directly producing sulfuric acid method titanium dioxide from non-blast furnace titanium slag, and belongs to the technical field of titanium non-acid treatment. Titanium slag generated through direct reduction of vanadium-titanium magnetite ores is taken as the raw material, neutralizing agent, and capturing agent of titanium hydrolysis and precipitation, through oxidation and hydrolysis, titanium in the waste acids of the titanium dioxide industry is precipitated and enriched in the optimized titanium slag; at the same time, rare metals such as vanadium, scandium, and the like, is extracted and dissolved in the solution so as to obtain a titanium poor solution containing rare metals such as vanadium, scandium, and the like, the titanium poor solution is extracted or subjected to ion exchange so as to recover vanadium, scandium, and the like; the optimized titanium slag is applied to titanium dioxide production through a sulfuric acid method; and the waste acids generated during the titanium dioxide production are returned and cyclically used. The problems of waste acid discharge and environmental pollution of sulfuric acid method titanium dioxide production are radically solved; and the provided method has the advantages that the titanium dioxide product quality is good, the titanium recovery rate is high, and rare elements such as vanadium, scandium, and the like, can be comprehensively recovered.

The invention relates to a preparation method for battery electrolyte, especially relates to a vanadyl-sulfate electrolyte preparation method applied to a full-vanadium flow cell. Compared with the prior art, the method takes vanadyl-sulfate solution, obtained through a conventional method for extracting vanadium from vanadium slags and stone coal, as an object. The pH value of the solution is adjusted through alkali metal or alkaline-earth metal oxides or hydroxides. The separation of vanadium and iron ions is achieved through revivification and a method of multi-segment multi-stage counter-current extraction. The concentration of vanadyl sulfate is adjusted through distillation, and a vanadyl sulfate electrolyte is manufactured directly. The method is simple in technology, is low in cost, and achieves scale production.

The invention discloses a method for recovering valuable elements from chlorination-process titanium dioxide waste acid through sectional extraction. The method comprises the following steps: S1, adding a first organic phase into the chlorination-process titanium dioxide waste acid to obtain a first extraction raffinate and an iron load, and carrying out back extraction on the iron load to obtaina ferric chloride solution; S2, adding a second organic phase into the first extraction raffinate to obtain second extraction raffinate and a scandium-titanium-zirconium-niobium load; S3, carrying outback extraction on the scandium load to obtain a scandium-titanium-zirconium-niobium enriched product; S4, adjusting the pH value of the second extraction raffinate to prepare a liquid; S5, adding athird organic phase after liquid preparation to obtain a vanadium-aluminum load and a third extraction raffinate; S6, carrying out back extraction on the vanadium-aluminum load to obtain a vanadium-aluminum mixed solution; S7, adjusting the pH value of the third extraction raffinate to prepare a liquid; S8, after liquid preparation, adding a fourth organic phase into manganese extraction feed liquid to obtain a manganese load and a fourth extraction raffinate, and carrying out back extraction on the manganese load to obtain a manganese-containing solution; and S9, neutralizing the fourth extraction raffinate, carrying out filtering, then performing concentrating and crystallizing to obtain NaCl edible salt and water, and recycling the NaCl edible salt and water.

The present invention is directed to a process for preparing vanadium pentoxide from an ash composition comprising solid ash particles, vanadium, iron and nickel compounds optionally present in an aqueous solution. The process comprises the following steps: (i) leaching the ash composition by contacting the ash composition with an acid aqueous solution at a pH of below 1, (ii) adding a reducing agent to the aqueous solution, (iii) contacting the aqueous solution obtained in step (ii) with an ion exchange resin in its H + ionic form, (iv) desorption of the vanadium compounds from the ion exchange resin rich in vanadium compounds by contacting the ion exchange resin with an aqueous solution of H 2 SO 4 to obtain an aqueous solution rich in vanadium compounds, and (v) converting and isolating the vanadium compounds as present in the aqueous solution to vanadium pentoxide.

The invention discloses a method for recycling ammonium paratungstate by using a waste SCR catalyst, which is used for recycling alkali liquor after an alkaline leaching reaction is finished, so thatthe production cost is further saved, and the recycled alkali liquor is used for carrying out water-soluble operation on crystals so as to realize the extraction of ammonium paratungstate, on the basis of cyclic utilization of the alkali liquor, PH adjustment through a large amount of acid liquor is avoided, and use of harmful chemicals is effectively reduced on the basis of improving the process.