Method for separating iron, chromium, nickel, copper and zinc from high-iron high-chromium electroplating sludge leachate

Abstract

The invention provides a method for separating iron, chromium, nickel, copper and zinc from high-iron high-chromium electroplating sludge leachate. The method comprises the following steps: (1) addingiron powder into the leachate to obtain a copper powder product and replaced liquid; 2) adding iron powder into the replaced liquid to obtain reduced liquid; (3) adding a chromium precipitating agentinto the reduced liquid, and carrying out filtering to obtain chromium-precipitated liquid and a chromium precipitate; (4) adding the activator antimony salt and zinc dust into the chromium-precipitated liquid, carrying out a reaction, and then carrying out filtering to obtain nickel powder and nickel-removed liquid; (5) adding an acidic phosphate extraction agent into the nickel-removed liquid to extract zinc, then carrying out reextraction by using dilute sulfuric acid, subjecting a zinc-rich solution to concentration and crystallization to prepare a zinc salt product, and subjecting zinc raffinate to subsequent treatment; and (6) subjecting the zinc raffinate to concentration and crystallization to prepare ferrous sulfate heptahydrate, and returning distilled water for leaching. The separation method of the invention has the advantages of short process and high efficiency, and can effectively solve the problem difficulties in separate separation of chromium, iron, nickel, copper and zinc metals in the high-iron high-chromium electroplating sludge leachate.

Description

technical field

[0001] The invention belongs to the field of multi-metal resource utilization in electroplating sludge, and in particular relates to a method for separating iron, chromium, nickel, copper and zinc in a leaching solution of high-iron and high-chromium electroplating sludge. Background technique

[0002] At present, the treatment and disposal methods of electroplating sludge mainly include: solidification and stabilization technology, thermochemical incineration disposal, and wet recycling and resourceful treatment and disposal. The principle of co-processing waste in cement kilns in the incineration method is to use the high temperature generated during the cement incineration process to process various residues and waste liquids in urban waste as raw materials for cement. This technology combines waste disposal with the sustainable development of the cement industry, and minimizes pollution discharge. It is an important technical approach for the harmless, re...

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