Method for reducing antimony content of crystallization byproduct in sodium sulfide alkaline wet process

Abstract

The invention discloses a method for reducing antimony content of a crystallization byproduct in a sodium sulfide alkaline wet process. The method comprises the following steps of: controlling the antimony concentration of an electrolyzed solution with the sodium sulfide concentration of over 180g/l, which is generated by an electrolytic bath in a wet process, to be between 4g/l and 7g/l; conveying the mixture into a jacketed stirring barrel by using a pump; starting a stirrer, continuously introducing a cooling liquid with the temperature of 0-5 DEG C into the jacket, continuously cooling thesolution in the barrel by utilizing the heat exchange of an interlayer, continuously stirring for 30 minutes at a constant temperature after the solution in the barrel is cooled to a certain temperature, and filtering the solution containing sodium sulfide crystal substances by virtue of a centrifugal machine so as to obtain sodium sulfide crystals with relatively low antimony content. Accordingto the method, the solubility difference between sodium sulfide in the solution and the antimony-containing compound in a certain temperature interval is large, so that sodium sulfide in the solutionis supersaturated, the antimony-containing compound is unsaturated, part of sodium sulfide can be crystallized and separated out, the antimony-containing compound still remains in the solution, and the antimony content of crystallization byproducts is reduced.

Description

technical field [0001] The invention relates to the field of antimony extraction, in particular to a method for reducing antimony contained in crystal by-products in the sodium sulfide alkaline wet process. Background technique [0002] Antimony metal element, which is a metalloid with metallic luster, mainly exists in the sulfide mineral stibnite in nature. Antimony compounds were used as cosmetics in ancient times. At present, the antimony minerals in the ore can be dissolved in alkaline sulfide In sodium solution, brittle-stimonite is a complex sulfide mineral rich in important metal elements such as Pb, Sb and Ag. It mainly extracts antimony from sodium sulfide alkaline solution. In industrial production, existing diaphragm electrodeposition and There are two methods of electrowinning without diaphragm. The former operation is more troublesome, but the current efficiency is high. my country adopts diaphragm electrowinning, and the composition of the catholyte is relativ...

AI Technical Summary

Problems solved by technology

The former operation is more troublesome, but the current efficiency is high. my country adopts diaphragm electrowinning, and the composition of the catholyte is relatively complicated, mainly Na3SbS3, and the anolyte is NaOH solution. The non-diaphragm electrowinning directly uses the leaching solution of Na2S and NaOH without additional supplementation. Add NaOH, and the crystal by-products formed in the alkaline wet process will contain a large amount of antimony, how to reduce the antimony into the crystal by-products is very meaningful to reduce the loss of antimony