9 results about "Chromium(III) hydroxide" patented technology

The invention discloses a chromium-containing wastewater treatment and recovery treatment line and a recovery treatment method thereof. The ion exchange system is used for carrying out ion exchange adsorption on the hexavalent wastewater; the alkali washing system is used for outputting alkali liquor to the ion exchange system; the washing system is used for outputting washing water to the ion exchange system; the pickling system is used for outputting acid liquor to the ion exchange system; the chromium recovery treatment branch line is used for receiving the hexavalent wastewater of the ion exchange system, mixing the hexavalent wastewater with sulfur powder and alkali liquor to prepare chromium hydroxide, then carrying out filter pressing on the chromium hydroxide, outputting a chromium hydroxide filter cake to the recovery calcination treatment line, and outputting a press filtrate to the press filtrate recovery branch line; the press filtrate recovery branch line is used for recovering sodium thiosulfate from the press filtrate; and the recycling and calcining treatment line is used for calcining the chromium hydroxide filter cake into Cr2O3. According to the scheme, the purposes of micro discharge and even zero discharge of the chromium-containing wastewater are achieved, and the problem that a large amount of chromium-containing hazardous waste sludge is generated by depending on a chemical reduction-precipitation method in traditional chromium-containing wastewater treatment is solved.

A recovery treatment line and method for chromium-containing wastewater; the recovery treatment line comprises a recovery reactor, a reducing agent feeder, a lye feeder and a recovery filter pressing system; the output end of the recovery reactor is communicated with the recovery filter pressing system, and is used for outputting chromium hydroxide wastewater to the recovery filter pressing system; a primary filter press is used for receiving the chromium hydroxide wastewater of the recovery reactor, and performing filter pressing treatment on the chromium hydroxide wastewater, outputting filtrate to a liquid phase recovery device, and outputting chromium hydroxide to a filter crushing device; the filter crushing device is used for performing crushing treatment on the chromium hydroxide, and outputting the chromium hydroxide to a cleaning tank; the cleaning tank is used for cleaning the chromium hydroxide, and outputting the chromium hydroxide to a secondary filter press; the secondary filter press performs filter pressing treatment on the chromium hydroxide of the cleaning tank, and obtains chromium hydroxide. The scheme solves the problem of high treatment difficulty of chromium-containing wastewater.

The present application relates to the technical field of chromium oxide preparation, and particularly relates to a preparation method of chromium oxide. The present application provides a preparation method of chromium oxide, comprising the following steps: after high-temperature leaching of a crude chromium hydroxide leaching solution, solid-liquid separation is performed to obtain a first solid phase and a first liquid phase; the first liquid phase is subjected to extraction to obtain an extraction phase and a raffinate phase; the raffinate phase is mixed with sodium hydroxide to perform chromium precipitation to obtain chromium hydroxide and a first chromium precipitation mother liquor; the chromium hydroxide is subjected to calcination to obtain chromium oxide; an extraction reagent used in the extraction includes an extractant and a diluent; the extractant includes two or more of P507, P204, TOPO, MIBK and TBP; and the diluent includes one or more of sulfonated kerosene, No. 260 solvent oil and isooctanol. The prepared chromium oxide has a main content of >98%, and can reach the smelting metal chromium level.

The invention belongs to the technical field of inorganic chemical industry, and particularly relates to a method for continuously preparing chromium hydroxide, which comprises the following steps: (1) heating a solution containing Cr < 6 + >, adding a reducing agent and a reducing auxiliary agent, maintaining the pH value of the system at 10-12, and carrying out a reduction reaction to obtain chromium hydroxide slurry; (2) standing and settling the obtained slurry, separating out two parts of chromium hydroxide slurry according to the volume ratio of (1.5-3): 1, and recycling the chromium hydroxide in the step (1) to control the growth of crystal nucleus; and (3) adding sulfuric acid and dilute sulfuric acid into the separated chromium hydroxide slurry step by step, adjusting the pH value of the system to 8-9, filtering, and washing until the pH value of washing water is 6.5-7.5 to obtain a target product. Through optimization of reaction conditions, introduction of the chromium hydroxide slurry and continuous process design, the problems of fine chromium hydroxide particles, high water content, low process efficiency and the like in the prior art are solved, and the method is suitable for the fields of chromium salt production, electroplating wastewater treatment, metal recovery and the like.

The application discloses a method for preparing chromium acetate from chromium hydroxide, which comprises the following steps: mixing chromium hydroxide wet filter cake with sulfonic acid group-chromium oxide composite mesoporous silica balls according to a proportion, adding glacial acetic acid, and then carrying out reaction, heating, separation, concentration crystallization and drying to obtain high-purity chromium acetate. The sulfonic acid group-chromium oxide composite mesoporous silica ball modified material is prepared by the following steps: first, synthesizing a mesoporous silica ball base by using a template agent, then loading chromium oxide and grafting a mercapto group by silanization, and finally oxidizing to obtain a sulfonic acid group functionalized material. The material can selectively adsorb impurity ions in situ in the reaction, so that the traditional complicated purification steps are simplified. The application has the advantages of simple operation, high product purity, and good industrial application prospect.

This invention provides a method for recovering vanadium, chromium, and sodium from a vanadium-chromium sodium salt solution: (1) Adjusting the pH value of the vanadium-chromium sodium salt solution, adding a chromium precipitation agent and performing a first hydrothermal reaction to obtain chromium hydroxide product and chromium precipitation mother liquor; sequentially performing a first washing and a first heat treatment on the chromium hydroxide product to obtain chromium oxide product; (2) Adjusting the pH value of the chromium precipitation mother liquor, adding a vanadium precipitation agent and performing a second hydrothermal reaction to obtain vanadium dioxide product and vanadium precipitation mother liquor; sequentially performing a second washing and a second heat treatment on the vanadium dioxide product to obtain vanadium pentoxide product; (3) Mixing the first washing residue from step (1), the second washing residue from step (2), and the vanadium precipitation mother liquor, and evaporating and crystallizing the resulting sodium-containing solution to obtain sodium carbonate product. This method avoids the introduction of sulfur and ammonia nitrogen from the source, generates no chromium-containing solid waste, and has a short process, clean process, and low energy consumption.

This invention provides a highly efficient method for separating and recovering iron, nickel, and chromium metal ions from sulfate solid waste, relating to the field of solid waste treatment technology. This invention uses column chromatography to separate sulfate solid waste, effectively separating and recovering iron, chromium, and nickel ions, filling a technological gap in the separation of these three metal ions. Compared to traditional chemical separation methods, this invention is not only simpler and faster with significant results, but also does not use or generate any harmful substances. The only solutions used throughout the process are water and anhydrous ethanol, making it environmentally friendly, extremely low-cost, and easily industrialized. Using the separation and recovery method provided by this invention, the recovery rates of iron, chromium, and nickel are high, all exceeding 96%. Furthermore, after processing the collected liquid according to appropriate methods, the resulting chromium hydroxide, nickel hydroxide, and ferrous oxalate have high purity, all exceeding 97%, and can be used in electrode materials for new energy batteries, demonstrating high resource utilization and good economic benefits.

A nonaqueous electrolyte solution battery lead wire of the present disclosure includes a conductor and an insulating film having one or a plurality of layers and covering at least part of an outer peripheral surface of the conductor. The conductor has a conductor film covering at least part of a surface thereof, the conductor film contains a trivalent chromium compound including chromium hydroxide and a metal element, a ratio of a mass of chromium contained in the chromium hydroxide per unit area [mg / m2] to a mass of chromium contained in the trivalent chromium compound per unit area [mg / m2] is 0.30 to 0.90 at an outermost surface of the conductor film, the insulating film has an innermost layer stacked on a surface of the conductor film, the innermost layer contains, as a main component, a resin component including maleic anhydride-modified polypropylene.

The invention provides a method for producing chromium hydroxide by using electroplating sludge. The invention relates to a method for producing chromium hydroxide by using electroplating sludge, which comprises the following steps: (1) slurrying: adding chromium-containing electroplating sludge into a slurrying kettle, adding a certain amount of water, and starting stirring for slurrying; according to the method, the chromium-containing waste liquid and the concentrated sulfuric acid are added into the pulpified electroplating sludge solution for leaching, a proper amount of sodium hypochlorite is added after more than half of the chromium sludge is dissolved, and alkali is added for neutralization after leaching is completed, so that impurity metals such as iron, aluminum, calcium and magnesium in the solution can be removed through a chemical precipitation method; and the follow-up chromium hydroxide preparation process is not interfered by the ions.