Method for recovering silver from waste circuit board

Abstract

The invention provides a method for recovering silver from a waste circuit board. The recovering method comprises the steps that firstly, the circuit board is disassembled, crushed and the like to obtain metal-containing powder, and then the metal-containing powder is mixed with a nitric acid solution for dipping extraction to form a silver-containing acid leaching solution; then, the obtained acid leaching solution is mixed with a specific emulsion for extraction, and silver ions are converted into silver simple substances to be extracted from the acid leaching solution; and then demulsification is performed, and the silver elementary substance is separated out. By means of the method, silver can be directly extracted and recovered from the leaching solution containing various metals, a separation process does not need to be set after wet treatment to obtain a single target metal solution for subsequent recovery operation, and the problems of base metal recovery and the like are not involved; and compared with the prior art, the technological process is greatly shortened and simplified, the extraction efficiency is improved, and the cost is relatively low.

Description

technical field [0001] The invention relates to the field of resource recycling, in particular to a method for recovering silver from waste circuit boards. Background technique [0002] At present, with the rapid development of communication technology, the national popularity of mobile phones is very high. Due to the rapid replacement of mobile phones, the average service life of each mobile phone is about two years, resulting in an increasing output of waste mobile phones. As the core component of the mobile phone, the circuit board is small in size. The gold content of the precious metal is about 0.86-1.6kg / t, and the silver content is about 0.14-5.8kg / t. It contains rich metal types and higher precious metals than primary minerals. It is also the part with the highest metal content and the most profitable recycling in waste mobile phones, and is known as the "urban mine". Mobile phone circuit boards are hazardous waste, containing a variety of harmful metals such as As...

AI Technical Summary

Problems solved by technology

The electrolysis method has high requirements on the separation process after wet treatment. Due to the complex metal components of the mobile phone circuit board, it is often difficult to obtain a high-purity target metal solution through the separation process, resulting in low purity of the recovered product, which needs to be purified again. At the same time It also consumes a lot of energy and is expensive

Before the replacement method is applied, it is generally necessary to set up a separation process, which consumes more base metals. In an alkaline environment, oxides or hydroxides are easily produced on the metal surface to inhibit the reaction. There are often base metal impurities in the product, and further purification is often required. At the same time, the treatment of base metals in waste liquid increases the process, the process is more cumbersome and the cost is higher

[0005] It can be seen that the above-mentioned traditional recycling methods usually have a series of problems such as complicated process, high cost consumption, low efficiency, heavy pollution, and large expenditures for the treatment of pollutants, resulting in the market price of used mobile phones and the value of materials after dismantling. Rather, the economic and environmental benefits of recycling technologies are facing enormous challenges as the number of end-of-life mobile phones grows day by day

Images