A kind of method that metallic copper is extracted from waste printed circuit board
Technical field
The invention belongs to material recovery field, is related to a kind of method for extracting metallic copper, and in particular to a kind of from waste and old print
The method that metallic copper is extracted in brush wiring board.
Background technology
Printed substrate(Printed circuit Bonds, PCBs)It is the base by resin and glass fiber material preparation
Copper rivet and copper foil and electronic component on plate, substrate etc. are formed.Printed substrate be widely used in information, communication,
The fields such as electronics, military affairs, space flight.With the continuous development of scientific technology and every field demand printed substrate continuous expansion
Greatly, the quantity of caused waste printed circuit board also sharp increase.A variety of in one side waste printed circuit board poisonous have
Evil material has to pass through recycling;Heavy metal element in another aspect waste printed circuit board substrate has high money again
Source recycles value, is a kind of potential secondary resource.Therefore, rationally effective recovery waste printed circuit board to economical and
Environmental protection suffers from important meaning.
At present, the technology for extracting metal from old circuit board both at home and abroad is mainly four kinds, i.e. mechanical treatment technology, Re Chu
Reason technology, hydrometallurgical technology and biotechnology.
Mechanical treatment technology mainly using physical method, realizes waste printed circuit board metal and non-gold by broken first
The dissociation of category, then metal and the difference of nonmetallic property contained by, are carried out these materials using different sorting methods
Separation.The mechanical treatment technology of discarded circuit board has:Disassemble, crush, pneumatic separating, magnetic separation, screening, vortex sorting, electric separation etc..
The method can preferably separate to metal with nonmetallic realization, and its flow is simple, to environment without destruction, but will be to useless during sorting
Old printed substrate substrate is crushed, and the purity of gained each component is not high after sorting, it is impossible to is directly recycled by industry.
Hydrometallurgical technology is that waste and old circuit board is handled with the acid of strong oxidizing property, then purifies the gold in leachate
Belong to ion, metal is reclaimed using replacing or being electrolysed handling process.The shortcomings that this method is that the strong oxidizers such as the nitric acid used can be
NO is discharged in processing procedureX, environment is polluted, and a large amount of waste liquids are generated, easily cause secondary pollution.In addition, with nitric acid, sulphur
When the strong acid such as acid are to leach the metal in substrate, on the one hand substrate nonmetallic materials can occur to aoxidize and be destroyed;On the other hand
The molecular structure that the metal ion of dissolving can also destroy nonmetallic materials on substrate makes the reduction of nonmetallic materials performance.
Heat treatment technics is that old circuit board is placed in high-temperature smelting pot to burn, and removes the inorganic components such as resin, Zhi Houzai
Utilize the noble metal in pyrogenic process and electrolysis recovery lime-ash.Disadvantage of this method is that:It can produce in burning process and largely also have
The smog of the noxious materials such as bioxin, furans and Polychlorinated biphenyls, secondary pollution and personal safety hidden danger be present.
Biotechnology is a kind of technology for carrying out specific absorption or cooperation to special metal ion using microorganism.This side
Method technique is simple, running cost is low, easy to operate, but the cultivation fee of microorganism is longer with larger and process cycle.At present, bioanalysis
Correlative study still in laboratory stage.
Hydrometallurgical technology and heat treatment technics grow up on the basis of metalliferous mineral smelting, technology more into
Ripe, cost is relatively low, and recovery metal purity is higher.Relative to heat treatment technics, hydrometallurgical technology needs to consume a large amount of chemistry examinations
The leaching of row metal is entered in agent, but technique is simply ripe, does not produce a large amount of toxic and harmful gas, and energy resource consumption is less, appropriate behaviour
Make that the pollution to environment can be greatly reduced.For hydrometallurgical technology, the key problem in technology for extracting copper is the leaching aspect of copper
And purity problem of copper of extraction etc..At present, the technology of conventional wet underwater welding copper is relatively cumbersome, is directed not only to the leaching of complexity
The configuration of copper system solution, can also be in extraction copper such as the selection and consumption of complexing agent, strong oxidizer, extractant, strippant
During produce a large amount of toxic and harmful gas pollution environment.
The content of the invention
One kind is provided the invention aims to overcome the deficiencies in the prior art gold is extracted from waste printed circuit board
Belong to the method for copper.
To reach above-mentioned purpose, the technical solution adopted by the present invention is:One kind extracts metal from waste printed circuit board
The method of copper, it comprises the following steps:
(a)The superficial layer of waste printed circuit board is separated from its substrate;
(b)Be negative electrode using the superficial layer as anode, titanium plate, copper-bath be electrolyte, connect dc source after shape
Into the electrolytic cell of open circuit;
(c)The spacing of regulation anode and negative electrode is 2 ~ 12cm, direct current power source voltage is 1 ~ 5V, the temperature of copper-bath is
25 ~ 50 DEG C, connect circuit and be electrolysed 0.5 ~ 5h, collect the copper obtained on negative electrode.
Optimally, the concentration of the copper-bath is 0.1 ~ 1mol/L.
Optimally, the copper-bath is obtained by the copper and sulfuric acid reaction obtained on negative electrode.
Because above-mentioned technical proposal is used, the present invention has following advantages compared with prior art:The present invention is from waste and old print
The method that metallic copper is extracted in brush wiring board using superficial layer as anode, titanium plate is negative electrode, copper-bath is that electrolyte forms electricity
Xie Chi, and electrolytic parameter is accurately controlled, high-purity volume copper can be obtained on negative electrode, can be directly used for industrial production;And make
Copper-bath can recycle, and will not cause secondary pollution to environment, because waste and old circuit board need not be crushed,
Not only simplify electrolysis process, the property of nonmetallic materials such as glass fibre is not damaged, expanded significantly secondly
Secondary utilization scope.
Embodiment
The method that the present invention extracts metallic copper from waste printed circuit board, it comprises the following steps:(a)By waste and old printing
The superficial layer of wiring board separates from its substrate;(b)Be negative electrode using the superficial layer as anode, titanium plate, copper-bath be electricity
Liquid is solved, breaking electrolytic cell is formed after connecting dc source;(c)The spacing for adjusting anode and negative electrode is 2 ~ 12cm, dc source
Voltage is 1 ~ 5V, the temperature of copper-bath is 25 ~ 50 DEG C, connects circuit and is electrolysed 0.5 ~ 5h, collects the copper obtained on negative electrode i.e.
Can.Be negative electrode using superficial layer as anode, titanium plate, copper-bath be that electrolyte forms electrolytic cell, and accurately control electrolytic parameter,
High-purity volume copper can be obtained on negative electrode, can be directly used for industrial production;And the copper-bath used can be circulated and made
With will not cause secondary pollution to environment, because waste and old circuit board need not be crushed, not only simplify electrolysis process, also make
The property of nonmetallic materials such as glass fibre is not damaged, and has expanded its secondary utilization scope significantly.Copper-bath
Concentration is preferably 0.1 ~ 1mol/L, and copper-bath is obtained by the copper and sulfuric acid reaction obtained on negative electrode, can so save sulphur
The dosage of sour copper, it is cost-effective, reduce the destruction to environment.
Step(a)In, it is by the specific method that the superficial layer of waste printed circuit board separates from its substrate:(S1)Take useless
Abandon wiring board and carry out differential scanning calorimetry respectively(DSC)And thermogravimetric analysis(TGA)Test analyzes curve corresponding to obtaining, it is determined that
Cracking temperature region;It should be noted that cracking temperature region needs to carry out comprehensive analysis according to DSC curve and TGA curves, it is first
Component or the temperature range of material fast degradation in discarded circuit board are determined first with TGA curves, then according on DSC curve
First main peak and second main peak determine cracking temperature region(Cracking temperature region is to second at first main peak peak value
Main peak initially forms temperature range corresponding to place, preferably 300 ~ 450 DEG C);(S2)Tube furnace is warming up to the cracking temperature
Any temperature in region, is continuously passed through inert gas(Inert gas flow can be adjusted according to actual process, as long as really
It is not oxidized to protect discarded circuit board), sample is then pushed away into boat feeding effectively heating warm area and carries out insulation 10 ~ 60 minutes, directly
Warpage occurs to metal level;(S3)Collection vessel is connected in the tube furnace exit, takes the gas discharged in pyrolytic process to enter
Promoting the circulation of qi analysis of hplc, recovery scheme is determined according to gas chromatographic analysis result, recycled(Caused by pyrolytic process
Pyrolysis gas and pyrolysis oil can be recovered, and carry out secondary use to make the energy or raw material, utilized with reaching the maximum of resource
Change);(S4)After the discarded circuit board cooling after pyrolysis, glass fabric and metal level are peeled off;The surface so obtained
Layer has higher quality, is advantageous to improve the yield of metallic copper.
The present invention is further described below in conjunction with embodiment.
Embodiment 1
The present embodiment provides a kind of method that metallic copper is extracted from waste printed circuit board, and it comprises the following steps:
(a)The superficial layer of waste printed circuit board is separated from its substrate;
(b)Be negative electrode using the superficial layer as anode, titanium plate, 0.1mol/L copper-baths be electrolyte, connect direct current
The electrolytic cell of open circuit is formed after power supply;
(c)The spacing of regulation anode and negative electrode is 12cm, the temperature of direct current power source voltage 1V, copper-bath is 50
DEG C, circuit electrolysis 5h is connected, collects the copper obtained on negative electrode;Because electrolysis time is longer, treat that copper-bath concentration becomes
After dilute, the copper that power taking solution obtains is added in sulfuric acid, is thermally formed copper-bath, is added in thinning previous solu, makes its dense
Degree keeps being about 0.1mol/L.
Embodiment 2
The present embodiment provides a kind of method that metallic copper is extracted from waste printed circuit board, and it comprises the following steps:
(a)The superficial layer of waste printed circuit board is separated from its substrate;
(b)Be negative electrode using the superficial layer as anode, titanium plate, 1mol/L copper-baths be electrolyte, connect direct current
The electrolytic cell of open circuit is formed behind source;
(c)The spacing of regulation anode and negative electrode is 2cm, the temperature of direct current power source voltage 5V, copper-bath is 25 DEG C,
Circuit electrolysis 0.5h is connected, collects the copper obtained on negative electrode.
Embodiment 3
The present embodiment provides a kind of method that metallic copper is extracted from waste printed circuit board, and it comprises the following steps:
(a)The superficial layer of waste printed circuit board is separated from its substrate;
(b)Be negative electrode using the superficial layer as anode, titanium plate, 0.5mol/L copper-baths be electrolyte, connect direct current
The electrolytic cell of open circuit is formed after power supply;
(c)The spacing of regulation anode and negative electrode is 5cm, the temperature of direct current power source voltage 3V, copper-bath is 30 DEG C,
Circuit electrolysis 2h is connected, collects the copper obtained on negative electrode.
The above embodiments merely illustrate the technical concept and features of the present invention, and its object is to allow person skilled in the art
Scholar can understand present disclosure and implement according to this, and it is not intended to limit the scope of the present invention, all according to the present invention
The equivalent change or modification that Spirit Essence is made, it should all be included within the scope of the present invention.