Chemical nickel-plating waste liquor treatment method and system

Abstract

The invention provides a chemical nickel-plating waste liquor treatment method and system. The chemical nickel-plating waste liquor treatment method comprises the steps of adjusting the pH value of chemical nickel-plating waste liquor to 8-8.5; adding soluble barium salt to conduct a complex breaking reaction, and adjusting the pH value of the solution to 11-12, and then conducting coagulating settling to obtain first mixed liquor; conducting solid-liquid separation on the first mixed liquor to obtain first filtrate; conducting subsequent purification treatment on the first filtrate to realize recycling and discharging. The chemical nickel-plating waste liquor treatment system comprises a complex breaking device and a first pressure filter connected with each other. By means of the chemical nickel-plating waste liquor treatment method and system, complex nickel in the chemical nickel-plating waste liquor can be destroyed to generate free nickel ions, so that nickel in the waste liquor is completely removed through a neutralization method. Compared with existing treatment methods, the purification effect is greatly improved.

Description

technical field [0001] The invention relates to the field of chemical nickel plating waste liquid treatment, in particular to a method and system for chemical nickel plating waste liquid treatment. Background technique [0002] Electroless nickel plating is a method of depositing a layer of nickel on the surface of metal products by means of oxidation-reduction without external current. It is widely used in various industries such as electronics, automobiles, and machinery. Since the 1990s in my country, the electroless nickel plating technology has entered a period of rapid development, and its process and coating performance have reached or approached the international level. During the production process, as the oxidation-reduction reaction proceeds, the reducing substances in the plating solution will continue to accumulate, and the speed of the oxidation-reduction reaction will gradually slow down, or even stop. At this time, it needs to be scrapped and replaced. [00...

AI Technical Summary

Problems solved by technology

In the electroless nickel plating solution, most of the complexing agents used are organic acids, such as citric acid, tartaric acid, malic acid, lactic acid, glycolic acid, succinic acid and acetic acid, etc. The complexing agent contains a variety of ligands, These ligands are combined with nickel ions to form a variety of nickel complexes. For example, the Ni-citric acid complex formed by the coordination of nickel and citric acid has a relatively large stability constant (its logK1=14.3). The neutralization method cannot make all the nickel ions react with OH- to form nickel hydroxide precipitation, and it is impossible to remove most of the nickel in the waste liquid.

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