A method for extracting copper from waste circuit boards by using moderately thermophilic bacteria

Abstract

The invention relates to a method for extracting copper in waste printed circuit boards by virtue of moderately thermophilic bacteria. The method comprises the following steps of carrying out shaker hydraulic sorting on the artificially dismounted and pulverized waste printed circuit boards to obtain metal and waste residues; putting the waste residues into an improved 9K culture medium, adjusting the pH value to 2 and leaching with a mixed strain of leptospirillum ferriphilum, acidithiobacillus caldus, sulfobacillus thermosulfidooxidans and thermoacidiferriphile as a leaching strain to obtain a copper-enriched solution and leaching residues; filtering the copper-enriched solution with a hollow fiber membrane system to obtain the strain and a copper-containing filtrate and putting the strain again into the leaching system for repeatedly using; and extracting the copper-containing filtrate with hydroxy oxime and a hydroxy oxime complex Lix984 as extraction agents to obtain a copper-loaded organic phase and a raffinate, carrying out back extraction on the copper-loaded organic phase with a 10-30% sulfuric acid solution to obtain a back extract and a blank organic phase and carrying out electrodeposition on the back extract to obtain cathode copper and an electrodeposited barren liquid. By the method disclosed by the invention, the environment-friendly, economic and full-value recovery of the waste printed circuit boards is achieved and the method has the advantages of short flow, low investment, high efficiency and low treatment cost and is suitable for the recovery of all types of the waste printed circuit boards.

Description

[0001] Technical field:

[0002] The invention belongs to the technical field of recovery and preparation of copper in waste printed circuit boards, and in particular relates to a method for extracting copper in waste circuit boards by using moderately thermophilic bacteria.

[0003] Background technique:

[0004] Waste printed circuit boards contain a large amount of metal substances, and the metal content in some circuit boards even exceeds 45%. The recycling of metal substances in them has been reported in relevant literature. Since copper is the main metal in printed circuit boards, the general content is about 15%, therefore, the potential for recovering copper from waste printed circuit boards is very large. Recycling copper from waste printed circuit boards can not only maintain the surrounding environment and ensure the welfare of residents, but also make up for the increasingly scarce copper resources.

[0005] At present, the methods for extracting copper from waste ...

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