阅读说明：本技术 一种pcb板的铜提取工艺 (Copper extraction process of PCB ) 是由 谢启银 于 2019-08-19 设计创作，主要内容包括：本发明提供了一种PCB板的铜提取工艺,通过预处理,拆除PCB板上的电子元件,将PCB板压碎并研磨成第一粉末,将第一粉末过筛,收集通过筛孔的第二粉末待处理；通过菌种备用,得到200～300mmol/L的Cu2+和呈酸性液态下的嗜酸氧化亚铁硫杆菌和嗜酸氧化硫硫杆菌备用；通过接种培养,初始PH为0.5～0.8的混合菌；通过混合处理,将混合菌与第二粉末混合反应150h～170h,然后进行旋转离心,离心后收集浸出液；通过后处理,将浸出液用铜萃取剂进行萃取,得到的含铜萃取液,用反萃取剂进行反萃取；然后将得到的含铜反萃液转移入电解槽中进行电积得到铜,从而完成废弃印刷电路板中铜的回收,从而实现提取PCB板内的铜金属且不会造成环境污染和资源浪费的技术效果。(The invention provides a copper extraction process of a PCB (printed Circuit Board), which comprises the steps of removing electronic elements on the PCB through pretreatment, crushing and grinding the PCB into first powder, sieving the first powder, and collecting second powder passing through sieve pores to be treated; obtaining 200-300 mmol/L Cu2+ and Acidithiobacillus ferrooxidans and Acidithiobacillus thiooxidans in an acid liquid state for later use through strain preparation; inoculating and culturing mixed bacteria with initial PH of 0.5-0.8; mixing the mixed bacteria and the second powder for reaction for 150-170 h, then carrying out rotary centrifugation, and collecting the leachate after centrifugation; performing post-treatment, extracting the leachate by using a copper extractant to obtain copper-containing extract, and performing back extraction by using a back extractant; and transferring the obtained copper-containing stripping solution into an electrolytic bath for electrodeposition to obtain copper, thereby completing the recovery of copper in the waste printed circuit board, and further realizing the technical effects of extracting copper metal in the PCB and avoiding environmental pollution and resource waste.)

1. A copper extraction process of a PCB is characterized by comprising the following steps:

preprocessing, namely dismantling electronic components on the PCB, crushing and grinding the PCB into first powder, sieving the first powder, and collecting second powder passing through sieve holes to be processed;

respectively carrying out Cu2+ culture on domesticated acidithiobacillus ferrooxidans and acidithiobacillus thiooxidans for later use to obtain 100-200 mmol/L acidithiobacillus ferrooxidans and acidithiobacillus thiooxidans in a Cu2+ environment, and then mixing with an acidic oxide to obtain 200-300 mmol/L Cu2+ and acidithiobacillus ferrooxidans and acidithiobacillus thiooxidans in an acidic liquid state for later use;

inoculating and culturing, namely inoculating and culturing 200-300 mmol/L of Cu2+, and Acidithiobacillus ferrooxidans and Acidithiobacillus thiooxidans in an acid liquid state, wherein the Acidithiobacillus ferrooxidans and the Acidithiobacillus thiooxidans are inoculated according to an inoculation ratio of 1: 2.5-3, culturing the mixed bacteria in the mixed bacteria culture solution so that the mixed bacteria with initial PH of 0.5-0.8 are cultured for 30-50 hours;

mixing, namely mixing the mixed bacteria and the second powder for reaction for 150-170 h, then carrying out rotary centrifugation, and collecting leachate after centrifugation;

performing post-treatment, namely extracting the leachate by using a copper extractant to obtain copper-containing extract, and performing back extraction by using a back extractant; and transferring the obtained copper-containing stripping solution into an electrolytic bath for electrodeposition to obtain copper, thereby completing the recovery of copper in the waste printed circuit board.

2. The process for extracting copper from a PCB according to claim 1, wherein in the step of inoculating and culturing, the mixed bacteria culture solution comprises the following components:

4.0-6.5 g/L of elemental sulfur, 3.5-4.5 g/L of ammonium sulfate, 0.45-0.65 g/L of dipotassium phosphate, 0.45-0.65 g/L of magnesium sulfate heptahydrate, 0.1-0.15 g/L of potassium chloride, 0.008-0.015 g/L of calcium nitrate, 15-18 g/L of ferrous sulfate heptahydrate and 0.10-0.18 g/L of calcium chloride;

the solute of the mixed bacteria culture solution is water.

3. The process for extracting copper from a PCB according to claim 1, wherein the mixed bacteria culture solution comprises the following components:

4.4-5 g/L of elemental sulfur, 3.75-4 g/L of ammonium sulfate, 0.5-0.6 g/L of dipotassium phosphate, 0.5-0.6 g/L of magnesium sulfate heptahydrate, 0.12-0.14 g/L of potassium chloride, 0.01-0.015 g/L of calcium nitrate, 17-18 g/L of ferrous sulfate heptahydrate, and 0.13-0.177 g/L of calcium chloride;

the solute of the mixed bacteria culture solution is water.

4. The process for extracting copper from a PCB of claim 1, wherein the step of preparing the strain comprises:

0.5g to 1g of the second powder is introduced into 00 to 300mmol/L of Cu2+, Acidithiobacillus ferrooxidans and Acidithiobacillus thiooxidans in an acid liquid state.

Technical Field

The invention relates to the technical field of PCB waste recovery, in particular to a copper extraction process of a PCB.

Background

At present, the electronic industry develops rapidly, the updating iteration of the PCB is very fast, and the PCB can be replaced when people pursue a faster data processing speed, so that waste products of the PCB are generated; the PCB contains a large amount of copper (about 20%), so how to solve the problem of environmental pollution caused by waste treatment of the PCB and the problem of effective recovery of copper metal are problems to be solved urgently;

at present, the known methods for diluting copper from the PCB board are a physical method and a chemical method; the physical method has good effects of resource regeneration and environmental friendliness, but the used mechanical equipment has large investment, high energy consumption and high maintenance cost, so the economic feasibility is relatively poor; and the metals in the product are difficult to separate. The chemical method mainly comprises a pyrogenic method and a wet method, wherein the pyrogenic method has the advantages of simplicity, convenience and high recovery rate, but has the defects of harmful gas generation, large scum discharge and the like; the wet method has the advantages of less waste gas discharge, easy treatment of residues after copper extraction, simple process and the like, but the copper leaching rate is low and the leachate and residues have toxicity. Therefore, the biological method with less pollution, low cost and mild reaction condition is applied to the metal recovery of the waste printed circuit board and has unique advantages.

Disclosure of Invention

The invention aims to realize the technical effect of extracting copper metal in a PCB and provides a copper extraction process of the PCB.

The invention adopts the following technical means for solving the technical problems:

the invention provides a copper extraction process of a PCB, which comprises the following steps:

preprocessing, namely dismantling electronic components on the PCB, crushing and grinding the PCB into first powder, sieving the first powder, and collecting second powder passing through sieve holes to be processed;

respectively carrying out Cu2+ culture on domesticated acidithiobacillus ferrooxidans and acidithiobacillus thiooxidans for later use to obtain 100-200 mmol/L acidithiobacillus ferrooxidans and acidithiobacillus thiooxidans in a Cu2+ environment, and then mixing with an acidic oxide to obtain 200-300 mmol/L Cu2+ and acidithiobacillus ferrooxidans and acidithiobacillus thiooxidans in an acidic liquid state for later use;

inoculating and culturing, namely inoculating and culturing 200-300 mmol/L of Cu2+, and Acidithiobacillus ferrooxidans and Acidithiobacillus thiooxidans in an acid liquid state, wherein the Acidithiobacillus ferrooxidans and the Acidithiobacillus thiooxidans are inoculated according to an inoculation ratio of 1: 2.5-3, culturing the mixed bacteria in the mixed bacteria culture solution so that the mixed bacteria with initial PH of 0.5-0.8 are cultured for 30-50 hours;

mixing, namely mixing the mixed bacteria and the second powder for reaction for 150-170 h, then carrying out rotary centrifugation, and collecting leachate after centrifugation;

performing post-treatment, namely extracting the leachate by using a copper extractant to obtain copper-containing extract, and performing back extraction by using a back extractant; and transferring the obtained copper-containing stripping solution into an electrolytic bath for electrodeposition to obtain copper, thereby completing the recovery of copper in the waste printed circuit board.

Further, in the step of inoculating and culturing, the mixed bacteria culture solution comprises the following components:

4.0-6.5 g/L of elemental sulfur, 3.5-4.5 g/L of ammonium sulfate, 0.45-0.65 g/L of dipotassium phosphate, 0.45-0.65 g/L of magnesium sulfate heptahydrate, 0.1-0.15 g/L of potassium chloride, 0.008-0.015 g/L of calcium nitrate, 15-18 g/L of ferrous sulfate heptahydrate and 0.10-0.18 g/L of calcium chloride;

the solute of the mixed bacteria culture solution is water.

Further, the mixed bacteria culture solution comprises the following components in percentage by weight:

4.4-5 g/L of elemental sulfur, 3.75-4 g/L of ammonium sulfate, 0.5-0.6 g/L of dipotassium phosphate, 0.5-0.6 g/L of magnesium sulfate heptahydrate, 0.12-0.14 g/L of potassium chloride, 0.01-0.015 g/L of calcium nitrate, 17-18 g/L of ferrous sulfate heptahydrate, and 0.13-0.177 g/L of calcium chloride;

the solute of the mixed bacteria culture solution is water.

Further, the step of preparing the strain comprises the following steps:

0.5g to 1g of the second powder is introduced into 00 to 300mmol/L of Cu2+, Acidithiobacillus ferrooxidans and Acidithiobacillus thiooxidans in an acid liquid state.

The invention provides a copper extraction process of a PCB, which has the following beneficial effects:

removing electronic components on the PCB through pretreatment, crushing and grinding the PCB into first powder, sieving the first powder, and collecting second powder passing through sieve holes to be treated; respectively carrying out Cu2+ culture on domesticated acidithiobacillus ferrooxidans and acidithiobacillus thiooxidans for later use through strains to obtain 100-200 mmol/L acidithiobacillus ferrooxidans and acidithiobacillus thiooxidans in a Cu2+ environment, and then mixing with an acidic oxide to obtain 200-300 mmol/L Cu2+ and acidithiobacillus ferrooxidans and acidithiobacillus thiooxidans in an acidic liquid state for later use; through inoculation culture, 200-300 mmol/L of Cu2+ and Acidithiobacillus ferrooxidans and Acidithiobacillus thiooxidans in an acid liquid state are subjected to inoculation culture, wherein the Acidithiobacillus ferrooxidans and the Acidithiobacillus thiooxidans are inoculated according to an inoculation ratio of 1: 2.5-3, culturing the mixed bacteria in the mixed bacteria culture solution so that the mixed bacteria with initial PH of 0.5-0.8 are cultured for 30-50 hours; mixing the mixed bacteria and the second powder for reaction for 150-170 h, then carrying out rotary centrifugation, and collecting the leachate after centrifugation; performing post-treatment, extracting the leachate by using a copper extractant to obtain copper-containing extract, and performing back extraction by using a back extractant; and transferring the obtained copper-containing stripping solution into an electrolytic bath for electrodeposition to obtain copper, thereby completing the recovery of copper in the waste printed circuit board, and further realizing the technical effects of extracting copper metal in the PCB and avoiding environmental pollution and resource waste.

Drawings

FIG. 1 is a schematic flow chart of an embodiment of the copper extraction process of the PCB of the present invention.

The implementation, functional features and advantages of the present invention will be further described with reference to the accompanying drawings.

Detailed Description

It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Referring to fig. 1, a schematic flow chart of a copper extraction process of a PCB according to an embodiment of the present invention is shown.

The invention provides a copper extraction process of a PCB, which comprises the following steps:

preprocessing S1, removing electronic components on the PCB, crushing and grinding the PCB into first powder, sieving the first powder, and collecting second powder passing through the sieve holes to be processed;

respectively carrying out Cu2+ culture on domesticated acidithiobacillus ferrooxidans and acidithiobacillus thiooxidans for later use to obtain 100-200 mmol/L acidithiobacillus ferrooxidans and acidithiobacillus thiooxidans in a Cu2+ environment, and then mixing with an acidic oxide to obtain 200-300 mmol/L Cu2+ and acidithiobacillus ferrooxidans and acidithiobacillus thiooxidans in an acidic liquid state for later use;

inoculating and culturing, namely inoculating and culturing 200-300 mmol/L of Cu2+, and Acidithiobacillus ferrooxidans and Acidithiobacillus thiooxidans in an acid liquid state, wherein the Acidithiobacillus ferrooxidans and the Acidithiobacillus thiooxidans are inoculated according to an inoculation ratio of 1: 2.5-3, culturing the mixed bacteria in the mixed bacteria culture solution so that the mixed bacteria with initial PH of 0.5-0.8 are cultured for 30-50 hours;

mixing, namely mixing the mixed bacteria and the second powder for reaction for 150-170 h, then carrying out rotary centrifugation, and collecting leachate after centrifugation;

performing post-treatment, namely extracting the leachate by using a copper extractant to obtain copper-containing extract, and performing back extraction by using a back extractant; and transferring the obtained copper-containing stripping solution into an electrolytic bath for electrodeposition to obtain copper, thereby completing the recovery of copper in the waste printed circuit board.

Specifically, the method adopts a biological method to treat the waste PCB, and abandons the traditional physical method and chemical method; in the preprocessing step S1, the PCB board with the electronic components attached thereto may be processed by a worker or a machine, the electronic components on the PCB board are detached, and then the PCB board is crushed by a hydraulic press or a crusher, and then the crushed PCB board is ground into the first powder by the grinder; the first powder is then sieved to remove excess PCB fragments that cannot be ground, thereby yielding a second powder.

From the above, the copper extraction method adopted by the present invention is a biological method for culturing bacilli for extracting copper, specifically, culturing Acidithiobacillus ferrooxidans and Acidithiobacillus thiooxidans, both of which are known to be acid bacteria for mixing the alkaline powdery substance in the second powder, while copper is inert and is not mixed by the acid bacteria. In step S2, the worker cultures the acclimated acidithiobacillus ferrooxidans and acidithiobacillus thiooxidans in Cu2+ to obtain 100-200 mmol/L of acidithiobacillus ferrooxidans and acidithiobacillus thiooxidans in Cu2+ environment, and mixes the acidithiobacillus thiooxidans and the acidithiobacillus ferrooxidans to obtain 200-300 mmol/L of Cu2+ and acidithiobacillus ferrooxidans and acidithiobacillus thiooxidans in acid liquid state for use, wherein the acid oxides include H2SiO 3.

In the step S3 of the inoculation culture, a worker performs inoculation culture on 200-300 mmol/L of Cu2+, and the acidophilic thiobacillus ferrooxidans and the acidophilic thiobacillus thiooxidans in an acid liquid state, wherein the ratio of inoculation of the acidophilic thiobacillus ferrooxidans and the acidophilic thiobacillus thiooxidans is 1: 2.5 to 3, culturing the mixed bacteria in the mixed bacteria culture solution so that the mixed bacteria with initial pH of 0.5 to 0.8 are cultured for 30 to 50 hours.

In the step S4 of the mixing process, the worker mixes the mixed bacteria with the second powder and reacts for 150 to 170 hours to test whether the mixed bacteria can effectively mix the alkaline substances in the second powder, so as to enhance or reduce the acid-base degree of the mixed bacteria in this way; and then, carrying out rotary centrifugation, and collecting a leachate after centrifugation, wherein the leachate contains copper, and the copper is easy to be centrifuged because the weight of the copper is higher than that of an alkaline substance mixed with the mixed bacteria.

In the above post-treatment step S5, the worker extracts the leachate with a copper extractant to obtain a copper-containing extract, and back-extracts the copper-containing extract with a back-extractant; then transferring the obtained copper-containing strip liquor into an electrolytic bath for electrodeposition to obtain copper, thereby completing the recovery of copper in the waste printed circuit board; specifically, a titanium plate is used as an anode and a copper plate is used as a cathode during electrodeposition. The voltage was controlled at 2.0V, the current density at 350A/m2, the pH at 3, the pole pitch at 1cm, the time at 3h and the temperature at 10 ℃. The copper extractant is 2-hydroxy-5-dodecyl benzophenone oxime, and the back extractant is copper electrolysis waste liquid. The recovery rate of electrodeposited copper was 99%. The recovered copper can reach the national GB/T6516-1997 standard. The electrodeposition solution is continuously circulated in order to keep the electrodeposition conditions substantially stable. In the embodiment, the titanium plate is used as the anode, so that the current can be efficiently transmitted to the electrolyte and used for anion discharge, and the electrodeposition efficiency is improved. In addition, the sulfuric acid generated in the process of electrodepositing copper can be recycled.

In one embodiment, in the step of inoculating and culturing, the mixed bacteria culture solution comprises the following components in percentage by weight:

4.0-6.5 g/L of elemental sulfur, 3.5-4.5 g/L of ammonium sulfate, 0.45-0.65 g/L of dipotassium phosphate, 0.45-0.65 g/L of magnesium sulfate heptahydrate, 0.1-0.15 g/L of potassium chloride, 0.008-0.015 g/L of calcium nitrate, 15-18 g/L of ferrous sulfate heptahydrate and 0.10-0.18 g/L of calcium chloride;

the solute of the mixed bacteria culture solution is water.

In one embodiment, the mixed bacteria culture solution comprises the following components in percentage by weight:

4.4-5 g/L of elemental sulfur, 3.75-4 g/L of ammonium sulfate, 0.5-0.6 g/L of dipotassium phosphate, 0.5-0.6 g/L of magnesium sulfate heptahydrate, 0.12-0.14 g/L of potassium chloride, 0.01-0.015 g/L of calcium nitrate, 17-18 g/L of ferrous sulfate heptahydrate, and 0.13-0.177 g/L of calcium chloride;

the solute of the mixed bacteria culture solution is water.

In one embodiment, the step of preparing the seed comprises:

0.5g to 1g of the second powder is introduced into 00 to 300mmol/L of Cu2+, Acidithiobacillus ferrooxidans and Acidithiobacillus thiooxidans in an acid liquid state.

In conclusion, through pretreatment, electronic components on the PCB are dismantled, the PCB is crushed and ground into first powder, the first powder is sieved, and second powder passing through the sieve holes is collected to be treated; respectively carrying out Cu2+ culture on domesticated acidithiobacillus ferrooxidans and acidithiobacillus thiooxidans for later use through strains to obtain 100-200 mmol/L acidithiobacillus ferrooxidans and acidithiobacillus thiooxidans in a Cu2+ environment, and then mixing with an acidic oxide to obtain 200-300 mmol/L Cu2+ and acidithiobacillus ferrooxidans and acidithiobacillus thiooxidans in an acidic liquid state for later use; through inoculation culture, 200-300 mmol/L of Cu2+ and Acidithiobacillus ferrooxidans and Acidithiobacillus thiooxidans in an acid liquid state are subjected to inoculation culture, wherein the Acidithiobacillus ferrooxidans and the Acidithiobacillus thiooxidans are inoculated according to an inoculation ratio of 1: 2.5-3, culturing the mixed bacteria in the mixed bacteria culture solution so that the mixed bacteria with initial PH of 0.5-0.8 are cultured for 30-50 hours; mixing the mixed bacteria and the second powder for reaction for 150-170 h, then carrying out rotary centrifugation, and collecting the leachate after centrifugation; performing post-treatment, extracting the leachate by using a copper extractant to obtain copper-containing extract, and performing back extraction by using a back extractant; and transferring the obtained copper-containing stripping solution into an electrolytic bath for electrodeposition to obtain copper, thereby completing the recovery of copper in the waste printed circuit board, and further realizing the technical effects of extracting copper metal in the PCB and avoiding environmental pollution and resource waste.

Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.