阅读说明：本技术 一种利用甘氨酸溶液浸提废旧印刷线路板中铜的方法 (Method for leaching copper in waste printed circuit board by using glycine solution ) 是由 陈梦君 韩昀晖 舒建成 王蓉 符俊灵 易小霞 于 2019-10-21 设计创作，主要内容包括：本发明公开了一种利用甘氨酸浸提废旧印刷线路板中铜的方法。其步骤为：通过拆解和机械破碎处理,获得粒径较小的废旧印刷线路板样品；搅拌条件下,将上述预处理样品置于甘氨酸和过氧化氢的混合浸出剂中,恒温浸出一段时间后,将浸出液过滤,浸出铜。本发明采用湿法冶金的方法,选用甘氨酸作为浸出剂浸提废旧印刷线路板中的金属铜,相较于传统浸出剂而言,具有环保性及高效性,铜的浸出率最高可达94%,是一种环保的处理方法。(The invention discloses a method for leaching copper in a waste printed circuit board by using glycine. The method comprises the following steps: obtaining a waste printed circuit board sample with smaller particle size through disassembly and mechanical crushing treatment; and (2) under the condition of stirring, placing the pretreated sample in a mixed leaching agent of glycine and hydrogen peroxide, leaching for a period of time at constant temperature, filtering the leaching solution, and leaching out copper. The method adopts a hydrometallurgy method, selects the glycine as a leaching agent to leach the metal copper in the waste printed circuit board, has environmental protection and high efficiency compared with the traditional leaching agent, has the highest leaching rate of the copper up to 94 percent, and is an environmental-friendly treatment method.)

1. A method for leaching copper in a waste printed circuit board by using glycine is characterized by comprising the following steps:

step 1: disassembling, shearing and crushing the waste printed circuit board to obtain a pretreated sample;

step 2: and (3) under the stirring condition, putting the pretreated sample into a mixed leaching agent of glycine and hydrogen peroxide, and leaching for a period of time at constant temperature.

2. The method of claim 1, wherein the waste printed wiring boards are disassembled, sheared and crushed to obtain a pretreated sample with a particle size of 1mm or less.

3. The method as claimed in claim 1, wherein the glycine concentration in the mixed leaching agent of glycine and hydrogen peroxide is 0.25 ~ 1.25.25 mol/L and the volume fraction of hydrogen peroxide is 2.5% ~ 10%.

4. A method as claimed in claim 1 or claim 3, wherein the ratio of pre-treated sample to combined leachant is 5 ~ 25 g/L.

5. The method of claim 1, wherein the constant temperature is from room temperature to 60 ℃ and the leaching time is greater than 480 min.

Technical Field

The invention relates to a method for recycling waste printed circuit board resources, in particular to a method for leaching copper in a waste printed circuit board by using glycine.

Background

In recent years, with the rapid development of electronic technology and electronic information industry, various electronic goods are coming up endlessly, various electronic devices such as mobile phones, computers, household appliances and the like are becoming more and more popular, the service life of electronic products is becoming shorter and shorter, and the replacement speed of electronic products is increasing, resulting in the rapid increase of the quantity of electronic waste. Printed wiring boards are one of the most important components in electronic equipment, and the number thereof is also increasing as the number of electronic waste increases. The waste printed wiring boards contain a large amount of metal resources including basic metals (Al, Cu, Fe, Ni, Pb, Sn, Zn, etc.), precious metals and rare metals (Au, Ag, Pd, Rh, Se, etc.), toxic heavy metals (As, Pb, Cd, etc.), among which the copper content is the highest. If the waste printed circuit board can be effectively recycled, the method not only can be used for the ecological environment, but also can be used for obtaining a large amount of copper resources through recovery.

The recovery processing of the waste printed circuit boards is started from the U.S. mining administration in 1969 for over a hundred years, and after exploration and research, the resource processing technology of the WPCBs has a solid theoretical foundation at home and abroad, and a plurality of mature processing technologies are searched. Currently, the most used treatment techniques are physical mechanical treatment, pyrometallurgical, hydrometallurgical, microbiological and supercritical fluid processes. Among them, the pyrometallurgical and physico-mechanical treatment methods have high equipment cost, high energy consumption, serious pollution, immature microbiological method and supercritical fluid method, low treatment capacity and not widely used. The hydrometallurgical technology is the most widely applied technology in a plurality of waste printed circuit board processing technologies, and is emphasized by various researchers due to simple operation and low energy consumption. Patent CN107574310A discloses a method for efficiently leaching copper in a waste circuit board, which is characterized in that multi-metal powder of the waste circuit board is mixed with sulfuric acid solution to be slurry, manganese oxide ore is added to be used as an oxidant to leach, the leaching rate of copper is more than 96%, however, the sulfuric acid solution is used as a leaching agent in the method, so that the method has certain danger, the human body is easily damaged due to improper operation, and acid waste liquid generated by leaching needs additional treatment.

Disclosure of Invention

In order to solve the problems, the invention provides a method for leaching copper in a waste printed circuit board by using glycine. The method is based on a hydrometallurgy technology, and the selected leaching agent is environment-friendly and safe, and has the characteristics of safe operation, simple process and no generation of acid-base waste liquid in the leaching process.

In order to achieve the purpose, the invention adopts the technical scheme that:

a method for leaching copper in a waste printed circuit board by using glycine comprises the following steps of using glycine to replace traditional inorganic acid as a leaching agent, using hydrogen peroxide as an oxidant, and leaching the copper in the waste printed circuit board under the condition of constant-temperature stirring:

step 1: disassembling, shearing and crushing the waste printed circuit board to obtain a pretreated sample;

step 2: and (2) under the condition of stirring, placing the pretreated sample in a mixed leaching agent of glycine and hydrogen peroxide, leaching for a period of time at constant temperature, filtering the leaching solution, and leaching out copper.

Further, the waste printed circuit board is disassembled, sheared and crushed to obtain a pretreatment sample with the grain size less than or equal to 1 mm.

Furthermore, in the mixed leaching agent of glycine and hydrogen peroxide, the concentration of glycine is 0.25-1.25 mol/L, and the volume fraction of hydrogen peroxide is 2.5-10%.

Further, the ratio of the pretreated sample to the mixed leaching agent is 5-25 g/L.

Further, the constant temperature is between room temperature and 60 ℃, and the leaching time is more than 480 min.

Compared with the prior art, the invention has the following beneficial effects:

(1) the method uses the glycine to replace the traditional inorganic acid to leach the copper in the waste printed circuit board, selects the hydrogen peroxide as the oxidant, does not add strong acid and strong base reagents, has safe operation process, low energy consumption and high leaching efficiency of the copper, and can reach more than 94 percent.

(2) The method has the advantages that the method is environment-friendly, no toxic and harmful byproducts are generated in the leaching process, no acid/alkali waste liquid is generated after leaching, the obtained product copper glycinate is harmless to the environment, and the subsequent treatment is convenient; compared with other organic acids, the glycine is cheap and easy to obtain.

Drawings

FIG. 1 is a process flow diagram of the method for leaching copper in waste printed circuit boards by using a glycine solution.

Detailed Description

The invention will now be described in more detail by way of the following examples, which are given for the purpose of better illustrating the invention, the scope of protection of the invention being not limited to the examples given.

With reference to fig. 1, the method for leaching copper in the waste printed circuit board by using glycine of the invention comprises the following steps:

step 1: the waste printed circuit board is disassembled, sheared, crushed and the like to obtain a pretreated sample;

step 2: preparing a glycine solution with a certain concentration;

and step 3: adding a certain amount of hydrogen peroxide into a glycine solution, uniformly mixing to obtain a mixed solution of glycine and hydrogen peroxide, and taking the mixed solution as a leaching agent;

and 4, step 4: under the magnetic stirring, adding a certain amount of the waste printed circuit board sample pretreated in the step 1 at a constant temperature, leaching for a period of time, immersing copper in the circuit board into the solution, and filtering the mixed solution.