Method for extracting and recovering Cr(III) from high acid solution

Abstract

The invention belongs to the field of pickling waste liquor resourceful treatment and particularly relates to a method for extracting and recovering Cr(III) from a high acid solution and application.The method comprises the following steps that (1) a double-cell electrolytic tank is fixed through a flat clamp, an anionic membrane with the diameter being around 2.5 cm is arranged in the joint position of the electrolytic tank, high acid pickling waste liquor is poured into an anode electrolytic cell, and a diluted sulfuric acid solution is poured into a cathode electrolytic cell; (2) both an anode and a cathode are lead plate electrodes with the size being 7cm*2cm*0.2cm, a direct current power supply is adjusted after powering-on is performed, electrolyzing is performed under certain current and certain voltage, and the Cr(III) can be oxidized into Cr(VI) after electrolyzing is performed; and (3) a certain amount of a solution obtained after electrolyzing is weighed, an equal amount ofan extraction agent diluted by means of a diluter is added, stirring is performed for a certain period of time in a thermostat water bath, and separation recovering is performed after layering occurs. The method provided by the invention has the advantages that a stoste system is kept, no secondary pollution occurs, the extraction speed is high, the Cr(III) is subjected to extraction separation recovering under high acid severe conditions, equipment is simple, and a great amount of alkali and precipitation reagents do not need to be added.

Description

technical field [0001] The invention belongs to the field of resource treatment of pickling waste liquid, and in particular relates to a method and application for extracting and recovering Cr(III) from a high-acid solution. Background technique [0002] Before steel is processed, it is usually soaked in acid at a certain temperature, or sprayed with a certain concentration of acid on its surface, in order to remove the oxide layer on the surface of the steel. This process is called pickling process. The pickling process can remove oxides and rust on the surface of steel, and is a method of cleaning metal surfaces that can improve the properties of steel surfaces. As the pickling process continues, the pickling efficiency increases with the concentration of metal ions in the clear liquid and the concentration of hydrogen ions decreases. Called pickling waste. According to the different acids used, it can be divided into sulfuric acid pickling waste, nitric acid pickling wa...

AI Technical Summary

Problems solved by technology

The neutralization method is cumbersome to manage, not easy to control, and the amount of wastewater treatment is restricted. In addition, the remaining acid and metals in the pickling wastewater cannot be utilized, and secondary pollution will be caused after neutralization treatment with drugs

The resource recovery method is the most used method in practice and experimentation, but harmful metal deposits are formed after neutralization by the steam acid method, and the investment and operation costs are high, the energy consumption is high, and the supplementary sulfuric acid consumption is large; the ion exchange technology produces a large amount of Treatment of waste liquid and dilute solution of metal salts, large consumption of tap water, small amount of treatment, not suitable for large-scale production

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