Wet harmless extraction process for metal in waste mobile phone circuit board

Abstract

The invention provides a wet harmless extraction process for metal in a waste mobile phone circuit board. The wet harmless extraction process solves the problem of metal recovery in the waste mobile phone circuit board in the prior art, and comprises the following steps that the waste mobile phone circuit board is disassembled into an IC chip, a surface mounted device and a light panel, a low-toxicity and environment-friendly leaching agent is developed, tin, copper silver and gold palladium are directionally and selectively leached by adopting a step-by-step method, and then tin, copper silver and gold palladium are reduced and extracted, the recovery rate of gold, silver and palladium reaches 95% or above, a suitable stripping agent is selected for stripping a gold plating on the light panel. According to the wet harmless extraction process, and various process units do not generate pollutants such as nitrogen oxide, sulfur dioxide and other countries strictly controlled by the totalamount, so that environmental pollution is reduced from the source.

Description

technical field [0001] The invention belongs to the technical field, and in particular relates to a wet harmless extraction process for metals in circuit boards of waste mobile phones. Background technique [0002] Among e-waste, discarded mobile phones are increasingly becoming the focus of e-waste recycling in the future due to their unique renewal speed and high recyclable value. The materials used in mobile phones can be roughly divided into two categories, one is glass fiber and resin materials, accounting for about 65.90%, which are mostly used in plastic casings, screens, speakers, cameras, etc. of mobile phones; the other is metal materials, about Accounting for 29.12%, mainly gold, palladium, silver, copper, tin, nickel, etc., basically exist in the metal casing and circuit board of the mobile phone. Mobile phones generally include 9 parts, namely: printed circuit boards, LCD screens, batteries, antennas, keyboards, microphones, speakers, casings and other accessor...

AI Technical Summary

Problems solved by technology

The disadvantage is that the final product is metal powder-enriched body and resin glass fiber powder, and the metal-enriched body needs to be further purified and separated by other processes

Compared with the waste circuit boards disassembled by the traditional "four machines and one brain", the waste mobile phone circuit boards are small in size, and the components are small patch components with complex structural components, low iron and aluminum content, high precious metal content, and many types. It is not suitable to adopt traditional crushing, physical separation, smelting and extraction processes. Relevant studies have shown that there is a negative correlation between the metal recovery rate of electronic waste and the efficiency of physical separation. The higher the efficiency of physical separation, the lower the recovery rate of precious metals. Mobile phone waste circuit boards If the traditional physical separation process is adopted, not only the efficiency of physical separation is low, but also the recovery rate of precious metals will be significantly reduced; due to the imperfect laws and regulations of waste mobile phones, the current recycling of waste mobile phones is still in the stage of extensive management and treatment. In the Guiyu model, the circuit boards are first incinerated to enrich metals, then leached with solutions such as aqua regia and cyanide, and then replaced by other methods to extract gold.

Wastewater and waste gas are discharged randomly, causing serious environmental pollution

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