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

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 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.