8 results about "Chromium product" patented technology

Hexavalent chromium (Cr (VI)) is widely applied to the industries of electroplating, spinning, leather tanning and chromium product manufacturing, and Cr (VI)-containing sewage has very strong biotoxicity and mutagenicity. Therefore, effective removal of Cr (VI) in industrial wastewater has important significance for protecting ecological environment and human health. As a novel bismuth-based oxychloride photocatalyst, the Bi4NbO8Cl material with the Aurivillius-Sillen structure has the advantages that the unique layered molecular structure of the Bi4NbO8Cl material is beneficial to the separation of photon-generated carriers, and the Bi4NbO8Cl material has good photocatalytic performance. On the basis of a Bi4NbO8Cl visible light response photocatalyst, the concentration of a glucose solution is regulated and controlled, carbon shell layers with different thicknesses are loaded, meanwhile, oxygen vacancy defects with different concentrations are formed, the visible light response Bi4NbO8Cl (at) C composite photocatalyst is obtained, and a good effect is achieved when the visible light response Bi4NbO8Cl (at) C composite photocatalyst is used for treating Cr (VI)-containing wastewater under the acidic condition.

The invention relates to a resourceful treatment method of a waste refractory material, which comprises the following steps: uniformly mixing the waste refractory material containing magnesium oxide and chromium oxide with sufficient carbon powder, and carrying out compression molding to obtain a material block; the material block is heated to the temperature T1 under the vacuum or protective atmosphere condition, so that the magnesium oxide in the material block reacts with the carbon powder to generate magnesium steam, and after the reaction is completed, a material block residual body is obtained; during the period, magnesium steam is collected and condensed to obtain metal magnesium; the material block residues are heated to the temperature T2 under the vacuum condition, after the reaction is completed, cooling is conducted, and coarse chromium is obtained; and after the coarse chromium is crushed, alkaline leaching, water washing, acid leaching, water washing and drying are conducted in sequence, and a metal chromium product is obtained. According to the invention, magnesium and chromium in the waste refractory material are recovered at the same time, the efficiency is high, the production energy consumption is reduced, and no wastewater or harmful waste gas is generated in the reaction process.

This application provides a method for selectively separating vanadium and chromium from chromium-vanadium slag leachate, relating to the field of solid waste recycling. The method includes: diluting a hydrophobic eutectic solvent with a diluent to obtain an extractant; mixing the extractant with the chromium-vanadium slag leachate, performing shake extraction, allowing the mixture to stand and separate phases to obtain a vanadium-loaded organic phase and a raffinate; washing and back-extracting the organic phase to obtain a vanadium-poor organic phase and a vanadium-rich back-extract; then subjecting the vanadium-rich back-extract to vanadium precipitation treatment and a first calcination to obtain vanadium pentoxide; the hydrophobic eutectic solvent is obtained by heating and stirring a mixture of a hydrogen bond donor and a hydrogen bond acceptor, wherein the hydrogen bond acceptor is composed of a neutral phosphorus-containing organic compound and a hydrophobic quaternary ammonium salt. This method can achieve selective separation of vanadium and chromium, effectively solving the problem of vanadium and chromium separation from chromium-vanadium slag leachate, and has good application prospects in the field of selective separation of vanadium and chromium to prepare high-purity vanadium and chromium products.

The application relates to a resource treatment method of waste refractory material, which comprises the following steps: mixing waste refractory material containing magnesium oxide and chromium oxide with sufficient carbon powder uniformly, and then pressing and forming to obtain a block; heating the block to a temperature T1 under vacuum or a protective atmosphere, so that the magnesium oxide in the block reacts with the carbon powder to generate magnesium vapor; after the reaction is completed, a residual block is obtained; during the process, the magnesium vapor is collected and condensed to obtain metallic magnesium; the residual block is heated to a temperature T2 under vacuum, and after the reaction is completed, the residual block is cooled to obtain crude chromium; after the crude chromium is crushed, the crude chromium is subjected to alkaline leaching, water washing, acid leaching, water washing and drying in sequence to obtain a metallic chromium product; the application realizes the simultaneous recovery of magnesium and chromium in the waste refractory material, has high efficiency, reduces production energy consumption, and does not generate waste water or harmful waste gas in the reaction process.

The invention provides a method for enriching and separating titanium, vanadium and chromium from titanium white waste acid, which comprises the following steps: mixing an alkaline substance containing calcium and / or magnesium with the titanium white waste acid to carry out acid-base neutralization reaction, reducing the acidity of the titanium white waste acid to precipitate titanium, vanadium and chromium, and carrying out reverse dissolution and precipitation by using sulfuric acid to obtain filtrate containing titanium, vanadium and chromium; freezing and filtering the filtrate containing titanium, vanadium and chromium to respectively obtain an aluminum ammonium sulfate crystal and the filtrate containing titanium, vanadium and chromium; then, the filtrate containing titanium, vanadium and chromium is diluted and hydrolyzed, the pH is adjusted, titanyl sulfate is hydrolyzed, sulfate of vanadium and chromium is not hydrolyzed, and metatitanic acid slurry and a diluted solution containing vanadium and chromium are obtained through separation; then neutralizing and filtering the vanadium-chromium-containing diluted solution to obtain a vanadium-chromium-containing filter cake; and then, the vanadium-chromium-containing filter cake is extracted and separated, and a chromium-containing product and a vanadium-containing product are obtained correspondingly. According to the method, high-value substances such as titanium, vanadium and chromium can be gradually separated and recovered, the problem that the high-value substances are difficult to separate and recover is solved, the enrichment and separation efficiency is improved, and the recovery and separation cost is reduced.

The invention discloses a method for separating vanadium and chromium ions in vanadium slag water leaching liquid, and belongs to the technical field of metallurgical chemical engineering, the method comprises the following steps: by taking the water leaching liquid obtained after sodium salt roasting of vanadium slag as raw material liquid, removing silicon, adjusting pH, adding a reducing agent to selectively reduce hexavalent chromium into trivalent chromium, and then adsorbing chromium in the solution by using cation exchange resin, thereby obtaining the vanadium and chromium ions in the vanadium slag water leaching liquid. Vanadium in the solution is subjected to vanadium precipitation to obtain vanadium pentoxide, then chromium on the resin is desorbed with an acid solution, the pH of the desorption solution is adjusted to form chromium precipitate, and chromium trioxide is obtained after roasting. According to the method, through collaborative innovation of selective reduction, strong acid cation exchange directional adsorption and an organic solvent-free process, the problems of incomplete separation of vanadium and chromium, low recovery rate and high cost in a traditional method are solved, efficient recovery of high-purity vanadium and chromium products is realized, and the method has both environmental protection property and economical efficiency.

The invention discloses a method for repairing chromium-contaminated soil through cooperation of microorganisms and natural iron-containing minerals, and the method comprises the following steps: mixing the natural iron-containing minerals into the chromium-contaminated soil, standing for several days, then adding mixed bacteria into the obtained system, standing for a reduction reaction, reducing high-valence iron and high-valence sulfur in the system into ferrous iron and ferrous sulfur, and then removing the ferrous iron and the ferrous sulfur in the system. A low oxidation-reduction potential environment is formed in the system; the method comprises the following steps: adding chromium reducing bacteria into a system in a low oxidation-reduction potential environment, standing and reducing hexavalent chromium to obtain trivalent chromium, and carrying out mineralization reaction on the trivalent chromium and ferrous iron to obtain a chromite-like product, thereby realizing the remediation of the chromium-polluted soil. According to the method provided by the invention, the natural iron-containing minerals, the mixed bacteria and the chromium reducing bacteria synergistically reduce and mineralize the hexavalent chromium, mineralization stable repair of the hexavalent chromium is realized, the problems of instability, easy re-dissolution and re-pollution and the like of a chromium product after traditional repair are solved, and the method has the advantages of short repair period, low construction cost and long-acting and stable effect, and is suitable for large-scale popularization and application. And the problem of secondary pollution in the treatment process is avoided.

The invention discloses a method for preparing chromium metal nitride by a carbon reduction sintering method, which comprises the following steps of: adding chromium green powder, an additive and an adhesive into a mixer, uniformly mixing, pressing into honeycomb briquette-shaped blocks by adopting a compression molding device, and drying in a drying furnace; putting the dried honeycomb briquette-shaped block into an intermediate frequency furnace, and sintering in a vacuum environment to obtain metal chromium; and after metal chromium sintering preparation is completed, the temperature in the intermediate frequency furnace is adjusted, a certain flow of nitrogen is introduced for nitridation, after cooling, crushing is conducted through a shaping machine, and nitrided metal chromium is obtained. The mixer is adopted for mixing materials, a three-dimensional and crushing mode is utilized, the mixing efficiency can be effectively improved, the production time is shortened, the production energy consumption is reduced, and meanwhile, the process is simple, parameters are easy to control, and the method is environmentally friendly and suitable for industrial production. And the obtained nitrided metal chromium product has the advantages of low impurity element content, strong metal luster, high density and good uniformity.