Unlock instant, AI-driven research and patent intelligence for your innovation.

A method for precipitation separation and recovery of vanadium and chromium in vanadium-chromium solution

A technology of precipitation separation and solution, applied in the direction of improving process efficiency, etc., can solve the problems of difficulty in obtaining high-concentration vanadium liquid, limited extraction agent capacity, and not suitable for transformation, and achieve fewer types, low anti-corrosion requirements, and water consumption. little effect

Active Publication Date: 2016-02-24
INST OF PROCESS ENG CHINESE ACAD OF SCI
View PDF5 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

This technology is relatively simple, and can obtain higher purity vanadium and chromium products, but due to the limited capacity of the extractant, it is difficult to obtain high-concentration vanadium liquid
The patent with the publication number CN101121962A is a vanadium-chromium separation method proposed by the applicant for an aqueous solution containing high concentrations of vanadium and chromium. Hydrate chromium hydroxide, use lye as the stripping agent, countercurrently contact the loaded organic phase to strip the vanadium to the water phase, and then use the ammonium salt precipitation method to prepare ammonium metavanadate. Clear liquid recovery of ammonia, this patented technology has a good effect on the separation of vanadium and chromium, and has been implemented and operated stably in the industry, but this technology is suitable for the new process of treating vanadium and chromium solution, not suitable for the transformation of the existing process flow

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • A method for precipitation separation and recovery of vanadium and chromium in vanadium-chromium solution

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0025] (1) Take 2L of vanadium-chromium mixed solution, which contains 1050ppmCr(VI) and 1090ppmV(V), heat it to 80 degrees, adjust the pH value to 3, and add 3 times the theoretical amount of ammonium sulfate to precipitate vanadium;

[0026] (2) Take 1L of vanadium precipitation tail liquid, which contains 1020ppmCr(VI) and 205ppmV(V);

[0027] (3) Add 0.5g composite reducing agent, adjust pH=2.3 with 1:1 sulfuric acid, stir for 10min; add 3mol / L caustic soda solution to adjust pH, precipitate and stand still;

[0028] (4) Pour out the supernatant and filter the precipitate at the bottom; add 0.25g composite reducing agent after mixing the filtrate and the supernatant, adjust the pH=2.2, stir for 10min, add caustic soda solution to adjust the pH=4.6, precipitate and let stand;

[0029] (5) Pour out the supernatant, filter the precipitate at the bottom; add 23g of composite reducing agent after mixing the filtered liquid and the supernatant, adjust the pH=2.3, stir for 10min,...

Embodiment 2

[0033] (1) Take 2L of vanadium-chromium mixed solution, which contains 1580ppmCr(VI) and 1255ppmV(V), heat it to 90 degrees, adjust the pH value to 1.6, and add 2 times the theoretical amount of ammonium sulfate to precipitate vanadium;

[0034] (2) Take 1L of vanadium precipitation tail liquid, which contains 1500ppmCr(VI) and 202ppmV(V);

[0035] (3) Slowly inject 1L containing 10% SO 2 The air is circulated through the closed air collection device until it is completely absorbed. Use 1:1 sulfuric acid to adjust pH=2.3, stir for 10 minutes; add 3mol / L caustic soda solution to adjust pH=7.5, precipitate and stand still;

[0036] (4) Pour out the supernatant, filter the precipitate at the bottom; mix the filtered liquid with the supernatant, and then slowly pass through 0.5L containing 10% SO 2 The air is circulated through a closed gas collection device until it is completely absorbed. Adjust pH = 2.2, stir for 10 minutes, add caustic soda solution to adjust pH = 4.6, preci...

Embodiment 3

[0042] (1) Take 10L of vanadium-chromium mixed solution, which contains 1020ppmCr(VI) and 2010ppmV(V), heat it to 80 degrees, adjust the pH value to 2.1, add 1.5 times the theoretical amount of ammonium sulfate and ammonium nitrate 1:1 mixed reagent Shen vanadium;

[0043] (2) Take 5L of vanadium precipitation tail liquid, which contains 990ppmCr(VI) and 180ppmV(V);

[0044] (3) Add a composite reducing agent that completely reduces the theoretical amount of 5%, adjust the pH=1.5 with 1:1 sulfuric acid, and stir for 60 minutes; add 5mol / L caustic soda solution to adjust the pH, precipitate and stand still;

[0045] (4) Pour out the supernatant, filter the bottom sediment; mix the filtered liquid with the supernatant, add 45% of the theoretical amount of complete reduction compound reducing agent, adjust the pH = 2.2, stir for 60 minutes, add caustic soda solution to adjust the pH = 6, and precipitate and stand still;

[0046] (5) Pour out the supernatant, filter the bottom s...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

The invention relates to a method for the precipitation separation and the recovery of chromium and vanadium in a chromium-vanadium solution. The method comprises the following steps: regulating the pH (Power Of Hydrogen) of a solution until the solution is acidic; adding an ammonium salt so as to precipitate the majority of vanadium from the solution in a form of ammonium polyvanadate; filtering and adding a certain amount of reducing agent into a vanadium-precipitated supernatant so as to perform reduction and precipitation on the partial vanadium in the solution; stirring and filtering; then adding the certain amount of reducing agent so as to reduce the rest of the vanadium in the precipitation solution; filtering; collecting filter residues obtained by two steps of reduction and precipitation; dissolving out in an oxidization manner and returning to the vanadium precipitation step via the ammonium salt; collecting the supernatants obtained by the two steps of reduction and precipitation; adding the certain amount of reducing agent again and precipitating chromium hydroxide; and filtering and calcining a filter cake so as to prepare chromium sesquioxide, wherein the supernatant after the precipitation of the chromic hydroxide can be taken as a mother liquor of a leaching process to be recycled. The method is simple in process, low in cost, less in equipment and small in reagent adding amount, and realizes the recycling of wastewater.

Description

technical field [0001] The invention relates to the field of hydrometallurgy or wastewater treatment, in particular to a method for precipitation, separation and recovery of vanadium and chromium in a solution containing vanadium and chromium. Background technique [0002] Both vanadium and chromium are important strategic resources, but high-valence vanadium and chromium have very strong toxicity, which poses a great threat to human health and the living environment. On the periodic table of elements, vanadium and chromium are adjacent to each other. The properties of the elements and their water chemical behavior are relatively similar, and they usually exist in various ores. During mineral processing and subsequent use, pentavalent vanadium and hexavalent chromium enter the aqueous solution at the same time. Because it is difficult to separate, it causes serious waste of resources and environmental pollution. [0003] For the recovery process of vanadium and chromium, th...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Patents(China)
IPC IPC(8): C22B3/44C22B34/22C22B34/32
CPCY02P10/20
Inventor 宁朋歌孙刚曹宏斌张懿
Owner INST OF PROCESS ENG CHINESE ACAD OF SCI