Method for recycling gold and cyanides in surface treatment wet-process cleaning solution

Abstract

The invention relates to a method for recycling gold and cyanides in a surface treatment wet-process cleaning solution, which comprises the following steps: filtering a plating solution or cleaning solution with a carbon fiber filter; carrying out electrodeposition treatment to precipitate gold and heavy metals to form a metal mixture, and carrying out separation treatment with a separating unit to adsorb residual gold; reacting white lime with boric acid to form a calcium borate precipitate, separating the calcium borate precipitate and citric acid with a nano filter membrane to form a regenerative solution, and storing the regenerative solution in a regenerative solution storage tank; dissolving gold in the metal mixture by using the regenerative solution, thereby forming a gold-containing solution; and separating the gold-containing solution with a reverse osmosis module to obtain an osmotic solution which osmoses through the reverse osmosis membrane and an unosmotic concentrated solution, wherein the osmotic solution is sent back to the regenerative solution storage tank. Therefore, the method provided by the invention can implement the goal of recycling gold by using the concentrated solution containing high-concentration gold potassium cyanide.

Description

technical field [0001] The invention particularly relates to a gold recovery method in a surface treatment wet process for resource recovery of gold contained in an electroless plating solution or cleaning solution. Background technique [0002] In the general surface treatment process of electroless gold plating or chemical gold plating, since the plating solution needs to use boric acid or dimethylamine-borane (Dimethylamine-borate, DMAB) as a reducing agent, it can be oxidized into a borate complex (borate complex). complex) and the gold in potassium cyanide gold is reduced to metallic gold and precipitated, so it is necessary to constantly replenish potassium cyanide gold to maintain the quality of the gold-plated layer. In addition, the pH value of the plating solution will change with the progress of the process. Therefore, it is necessary to add citric acid and potassium hydroxide as an acid-base buffer solution to adjust the pH value to the required range, and the ab...

AI Technical Summary

Problems solved by technology

[0005] However, the disadvantage of the existing technology is that the gold recovery equipment is not only expensive but also complicated to operate, so it is not combined with the original gold plating equipment, such as the plating tank body, so that the manufacturing cost cannot be further reduced, and the waste liquid generated in the gold plating process May contain cyanide, borate complexes, hydroxyl acid (hydroxyl acid) complexes (such as citrate complexes, phosphate complexes), under the rise of environmental awareness and the stricter regulations , the industry must have the ability to handle on-site

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