A kind of method for reclaiming of PCB nitric acid spent solder stripper
Technical field
The present invention relates to PCB tin removal waste liquor technical field of regeneration, and in particular, to a kind of PCB nitric acid spent solder stripper
Method for reclaiming.
Background technique
PCB (printed wiring board) is the supporter of electronic product component, is that the most basic hardware of current information-intensive society carries
Body, PCB (printed wiring board) industry are the pillar industry of China's electronics and IT industry, growth rate and electronics and information industry in same
Ratio increases.The PCB production practices of decades, production technology has very big improvement, but draws line map in the circuit board
The method that method still uses chemical medicinal liquid to etch.It is 5-8 μm that a layer thickness, which need to be plated, in patterned surface when outer layer Production of prints
Tin again dissolves the tin on surface layer after etch-forming.Nitric acid type etching agent is the leading dosage form of PCB production at present, generally with nitric acid
It is selection there are also sustained release agents, the effect such as nitric acid stabilizer, nitrogen oxides inhibitor and sulfonate, ferric nitrate for principal component
Dissolves surface layer tin and avoid etch pattern copper face to property.
During moving back tin, after the Theil indices of solution reach a certain concentration (usual high 100g/L), the decline of tin ability is moved back, from
It moves back and is discharged in tin equipment and becomes tin removal waste liquor.Tin removal waste liquor is that a kind of acidity for generating in PCB production process is very high, and contains
There is the dangerous waste liquid of the gas chromatographies such as the metallic compounds such as a large amount of tin, copper, iron and stabilizer, corrosion inhibiter, it is complex in composition, it is comprehensive
Recovery difficult is big.
Current domestic PC B enterprise year generates 50,000 tons or more of tin removal waste liquor according to statistics, currently, processing tin removal waste liquor patent
There are many method, refer to add carbonic acid into tin removal waste liquor in Chinese invention patent ZL101532096A and ZL 102775197A
The method for the method Separation of Tin that sodium, sodium hydroxide, ammonia precipitation process are boiled in conjunction with heating;In ZL101497458A and ZL1569644A
It refers to addition surfactant, flocculant, sodium hydroxide and barium chloride etc. and obtains barium stannate;It is referred in ZL101918133A
Add the method that electrolyte+distillation method obtains sodium stannate and stannic oxide;Addition lime is referred in ZL102086073A
Slurry+evaporating concentrating method separates metal cations, and adds the recycling processing method that additive realizes full recycling and zero-emission;
It is referred in ZL1288075 with+extraction and separation are boiled, ionic adsorption+electronation precipitates+is boiled equal physics+Chemical Decomposition and returned
The method for receiving metal ion, rear end add a certain amount of additive and realize recycling for tin removal waste liquor;ZL202080977,
A kind of adding sodium hydroxide precipitating+plate-type filtering+electrolysis mentions copper+is referred in CN102766883A and ZL202499890 adds one
Determine the method and apparatus that raw material realizes separation metal cation and recycles tin stripper;Patent CN102492860A and
The method by isolated tin mud of chemical substances such as addition electrolyte, flocculants is referred in CN102515259A.
From above processing method it can be found that recycling valuable metal in tin removal waste liquor primarily directed to property, for example add
Add chemical substance such as electrolyte, flocculant, alkali neutralization, the tin in extractant recycling tin removal waste liquor, copper, iron.Tin removal waste liquor nitre
Acid concentration is 4.0-4.5mol/L (being newly 5.5-6.0mol/L with concentration of nitric acid in tin-stripping solution), and traditional processing method is by nitre
Acidification is that nitrate discharges, in tin stripping liquid the utilization rate of nitric acid less than 35%, although have publication introduction by evaporation or
Extracting process recycles nitric acid, but rarely has industrialized report because operating cost is high or the concentration of nitric acid of recycling is too low.CN
103436885 A by tin removal waste liquor add organic acid come so that tin precipitate, then plus after flocculant be separated by solid-liquid separation,
Separating obtained filtrate adds nitric acid etc. and tin removal waste liquor recovery is made to move back tin ability, but from the point of view of practical experience, because because of organic acid, wadding
Solidifying residual of the agent in filtrate will affect move back tin after copper surface quality, while tin stripping liquid is regenerated compared with new tin stripping liquid, in work
A large amount of tin mud can be generated in work and are deposited in cylinder bottom, and blocking moves back tin nozzle, seriously affects PCB production efficiency, can in production application
Row is not high, and the valuable metal in addition recycled from tin removal waste liquor is mixed compound, needs further to divide by pyrometallurgical smelting
From tin, copper, iron, not only cost recovery is high, and the risk of secondary pollution environment is inevitably present in smelting process.
Summary of the invention
To overcome the problems, such as present on, the present invention provides a kind of method for reclaiming of PCB nitric acid spent solder stripper, should
Method is separated metal ion with metal ion capturing agent from tin removal waste liquor, and the tin removal waste liquors of separating metal ions is into one
Purification and impurity removal is walked, nitric acid, copper protective agent, tin complexing agent is then added and is configured to regeneration tin stripping liquid and be back to use PCB and move back tin production line,
Isolated precipitation by metallic ion object is dissolved with hydrochloric acid, electricity then is carried out to metal ion solution with electrolyzer with dual membranes and three chambers
Solution deposition recycling obtains metallic tin, metallic copper, liquor ferri trichloridi, hydrochloric acid solution, hydrochloric acid solution reuse to precipitation by metallic ion
Object dissolution process;This method not only isolated from tin removal waste liquor metal ion and by method for electrodeposition obtain metallic tin,
Copper and ferric chloride purifying agent, but also to the further impurity and purification of tin removal waste liquor add after effective component reuse to PCB and move back tin
Production line realizes nitric acid spent solder stripper regeneration.
In order to achieve the above object, nitric acid spent solder stripper method for reclaiming of the present invention, includes the following steps:
(1) in nitric acid spent solder stripper tin copper metal ion precipitation and separation: by a certain amount of tin removal waste liquor be added react
Slot opens stirring, and metal ion capturing agent is added and makes tin, copper, ferrous ion precipitating, tin copper and iron mixed precipitation is obtained by filtration
Object and filtrate;
In order to enable tin copper is effective to obtain precipitation and separation, metal ion capturing agent described in this step is can be with tin copper in nitric acid body
Lower organic acid, the acylate for forming precipitating of system, including oxalic acid, acetic acid, lactic acid, ammonium oxalate, ammonium acetate, ammonium lactate, in order to make
It obtains the effective precipitation and separation of tin copper and does not influence the quality of tin removal waste liquor regeneration, the additive amount of capturing agent is tin removal waste liquor body
Long-pending 1%-6%, capturing agent are stirred to react -6 hours 2 hours after being added, so that reaction is more abundant, after stopping stirring, stand 12-
It is separated by solid-liquid separation after 24 hours (A-si seasoning effect being played, so that tin copper and iron sediment is easier to carry out being separated by solid-liquid separation), obtains tin
Copper and iron sediment and filtered fluid;
(2) tin removal waste liquor filtrate deep impurity-removing purifies: it is net that cleaner progress deep impurity-removing is added in filtrate obtained by step (1)
Change, belongs to organic matter because remaining the copper-protection agent of failure, tin complexing agent, excessive metal ion capturing agent in tin removal waste liquor, this
Step preferably has the cleaner of suction-operated, including active carbon, sawdust slag, diatomite, the ratio of cleaner addition to organic matter
Example is the 0.5%-2% of filtrate volume, is stirred 2-6 hours after addition, after being then allowed to stand 12-24 hours, after purification is obtained by filtration
Tin removal waste liquor;
(3) allotment nitric acid type moves back tin regenerated liquid: surge-tank is added in tin removal waste liquor after purification obtained by step (2), adds nitre
Acid, promotor, tin complexing agent, copper-protection agent etc. are deployed into regeneration tin stripping liquid,
In order to enable regeneration tin stripping liquid not increment (tin removal waste liquor after regenerating with newly match to move back tin midnight's volume suitable), nitre
The nitric acid that sour preferred mass concentration is 62% or more, in order to which that accelerates regenerated liquid moves back tin speed, the preferred ferric nitrate of promotor or three
Iron chloride needs to be added tin complexing agent in regeneration tin stripping liquid in order to enable moving back the tin stripping liquid after tin does not generate tin mud precipitating, excellent
Select phenylfluorone, additive amount is the 0.005%-0.05% for regenerating tin stripping liquid volume, in order to slow down regeneration tin stripping liquid to moving back copper after tin
The corrosion in face regenerates and needs to add copper-protection agent, the preferred thiocarbamide of copper-protection agent, Ben and San Dan Cuo in tin stripping liquid, and additive amount is that regeneration is moved back
The 0.05%-0.15% of tin liquor volume;
(4) dissolution of tin copper and iron sediment: being first added a certain amount of hydrochloric acid in a kettle, and the additive amount of hydrochloric acid is tin copper
Iron precipitate is completely dissolved 1.1-1.2 times of required stoichiometry, opens stirring, and step (1) resulting tin copper and iron is then added
Mixed sediment is warming up to 90-100 degrees Celsius, so that sediment is completely dissolved, adds pure water and obtains tin ion concentration and maintain
The stannic chloride copper and iron hydrochloric acid solution of 6%-9% concentration;
(5) tin copper is recycled using electrolyzer with dual membranes and three chambers electrolytic deposition: stannic chloride copper and iron solution obtained by step (4) is injected
The hydrochloric acid solution of 0.5%-1% mass concentration, anode chamber's injection are injected in the cathode chamber of electrolyzer with dual membranes and three chambers, intermediate isolating room
The sulfuric acid solution of 0.5%-5% mass concentration, cathode use titanium plate, and anode is using the titanium insoluble anode for being coated with noble metal, in room
Be electrolysed under conditions of temperature, cathode produces successively copper electrowinning, tin metal on plate, the chloride ion that cathode chamber generates by anion from
Proton exchange enters intermediate compartment, and anode generates oxygen and hydrogen ion, and hydrogen ion enters intermediate compartment through cation-exchange membrane,
Electrolysis terminates to extract intermediate compartment hydrochloric acid solution into dissolution process of the reuse to step (4) tin copper and iron sediment, cathode chamber copper and tin out
The mixed solution of iron chloride frerrous chloride is obtained after electrodeposit;
Electrolyzer with dual membranes and three chambers anode chamber and intermediate compartment are separated with cation ion-exchange membrane, intermediate compartment and cathode chamber
Separated with anionic ion exchange membrane;
The electrochemical reaction that this process mainly occurs is:
Anode chamber: 2H2O→4H++O2
Cathode chamber: SnCl4→Sn+4Cl-CuCl2→Cu+2Cl-
Middle compartment: H++Cl-→HCl
(6) ferric trichloride is prepared:
Iron chloride solution of ferrous chloride obtained by step (5) is passed through oxygen caused by step (5) anode chamber and makes ferrous iron
Further oxidation obtains liquor ferri trichloridi, and liquor ferri trichloridi obtained by this step may be used as the flocculant of sewage treatment.
The beneficial effect that the present invention is different from the prior art is:
1, by the deep purifying of the tin removal waste liquor to precipitation and separation tin copper after ferrous, residual failure additive pair is solved
The influence of tin rear surface is moved back, further, deep purifying has also been removed influence of the excessive metal capturing agent to tin effect is moved back, regenerated liquid
Adding tin complexing agent, copper-protection agent etc. makes regenerated liquid move back tin speed, erosion copper speed, move back copper surface and new tin stripping liquid indifference after tin
Not, so that tin removal waste liquor regeneration technology is industrially feasible, the risk of tin removal waste liquor transfer secondary pollution environment is avoided;
2, tin removal waste liquor recycling gained tin copper and iron mixed compound is further processed, and recycling obtains metallic tin copper and tri-chlorination
Silicic acid avoids high energy consumption, the air pollution problems inherent of traditional fire concentrate tin copper and iron.
Detailed description of the invention
The drawings described herein are used to provide a further understanding of the present application, constitutes part of this application, this Shen
Illustrative embodiments and their description please are not constituted an undue limitation on the present application for explaining the application.In the accompanying drawings:
Fig. 1 is the process flow chart of PCB nitric acid spent solder stripper method for reclaiming of the invention;
Fig. 2 is the structural schematic diagram of electrolyzer with dual membranes and three chambers of the invention.
Specific embodiment
Embodiment 1
2000L tin removal waste liquor is added and reacts by certain PCB factory tin removal waste liquor stanniferous 6%, copper 0.5%, nitric acid 4.5mol/L
Kettle opens stirring, is added 20Kg oxalic acid (1% waste liquid volume ratio), is stirred to react 5 hours, stops stirring, it is small to staticly settle 12
When, it is separated by solid-liquid separation, obtains tin copper and iron mixed sediment and filtered fluid;1500L filtered fluid is pumped into reaction kettle, 30Kg (2% is added
Filtrate volume ratio) diatomite stirring 2 hours, 24 hours are stood, purified tin removal waste liquor is obtained by filtration;After 1000L is purified
Tin removal waste liquor is pumped into regeneration tin stripping liquid surge-tank, opens stirring, and the nitric acid that addition mass concentration is 68%, which is deployed to regeneration, moves back tin
Liquid acid concentration is 6mol/L, is added 0.5Kg tin complexing agent phenylfluorone (waste liquid volume ratio 0.05%), three nitrogen of 5Kg copper-protection agent benzo
Cuo, 50 kilograms are moved back tin promotor Fe(NO3)39H2O and are configured to nitric acid regeneration type tin stripping liquid reuse and move back tin production line to PCB;
Embodiment 2
Reaction kettle is added in gained tin removal waste liquor after the nitric acid regeneration type tin stripping liquid reuse production line of 1000L embodiment 1, is opened
Stirring is opened, is added 60Kg ammonium oxalate (2% waste liquid volume ratio), is stirred to react 5 hours, stops stirring, staticly settles 15 hours, Gu
Liquid separation, obtains tin copper and iron mixed sediment and filtered fluid;800L filtered fluid is pumped into reaction kettle, 8Kg (1% filtrate body is added
Product ratio) stirring of sawdust slag 2 hours, 15 hours are stood, purified tin removal waste liquor is obtained by filtration;Tin removal waste liquor after 800L is purified
It is pumped into regeneration tin stripping liquid surge-tank, opens stirring, the nitric acid that mass concentration is 68% is added and deploys to regeneration tin stripping liquid acid concentration
For 6mol/L, it is added 0.08Kg tin complexing agent phenylfluorone (waste liquid volume ratio 0.01%), 8Kg copper-protection agent thiocarbamide, 40 kilograms are moved back tin
Promotor ferric trichloride is configured to nitric acid regeneration type tin stripping liquid reuse and moves back tin production line to PCB;
Embodiment 3
2000L tin removal waste liquor is added and reacts by certain PCB factory tin removal waste liquor stanniferous 8%, copper 0.2%, nitric acid 4.1mol/L
Kettle opens stirring, is added 120Kg oxalic acid (6% waste liquid volume ratio), is stirred to react 5 hours, stops stirring, it is small to staticly settle 24
When, it is separated by solid-liquid separation, obtains tin copper and iron mixed sediment and filtered fluid;1500L filtered fluid is pumped into reaction kettle, 7.5Kg is added
(0.5% filtrate volume ratio) active carbon stirs 2 hours, stands 12 hours, purified tin removal waste liquor is obtained by filtration;By 1000L
Tin removal waste liquor is pumped into regeneration tin stripping liquid surge-tank after purification, opens stirring, and the nitric acid that mass concentration is 68% is added and deploys to again
Raw tin stripping liquid acid concentration is 6mol/L, is added 0.05Kg tin complexing agent phenylfluorone (waste liquid volume ratio 0.005%), 15Kg copper-protection agent
Ben and San Dan Cuo, 30 kilograms are moved back tin promotor Fe(NO3)39H2O, and 20 kilograms of ferric trichlorides are configured to nitric acid regeneration type tin stripping liquid
Reuse moves back tin production line to PCB;
Embodiment 4
Attached drawing 1-2 is please referred to, takes tin copper and iron sediment obtained by a certain amount of embodiment 1-3, stoichiometrically 1.1 extraordinarily
Enter hydrochloric acid, stirring and dissolving under conditions of 90 degrees Celsius adds pure water to be deployed into the stannic chloride copper and iron that tin ion mass concentration is 6%
Hydrochloric acid solution, by the cathode chamber 1 of solution injection electrolyzer with dual membranes and three chambers, intermediate compartment 3 injects 0.5% mass concentration
The sulfuric acid solution of 0.5% mass concentration injects in hydrochloric acid solution, anode chamber 2, and room temperature (25 degrees centigrade) opens electrolytic deposition gold
Belong to copper and tin, the chloride ion that cathode chamber 1 generates enters intermediate compartment 3 by anionic ion exchange membrane 4, and anode generates oxygen and hydrogen
Ion, hydrogen ion enter intermediate compartment 3 through cation-exchange membrane 5, and electrolysis terminates to extract back out the hydrochloric acid solution of intermediate compartment 3
With the dissolution process to tin copper and iron sediment, the mixing that iron chloride frerrous chloride is obtained after cathode chamber copper and tin electrodeposit is molten
Compartment 3 in liquid is enriched with hydrochloric acid, obtains metal copper and tin on cathode plate, and tin copper electrodeposition terminates, and extracts cathode chamber 1 out respectively
Lean electrolyte (solution of ferrous chloride) and 3 hydrochloric acid solution of intermediate compartment are spare;
Embodiment 5
Attached drawing 1-2 is please referred to, takes tin copper and iron sediment obtained by a certain amount of embodiment 1-3, stoichiometrically 1.2 extraordinarily
Enter hydrochloric acid (in addition the preferential hydrochloric acid solution collected using 4 intermediate compartment of embodiment, insufficient section are added) in 100 degrees Celsius of items
Stirring and dissolving under part adds pure water to be deployed into the hydrochloric acid solution for the stannic chloride copper and iron that tin ion mass concentration is 9%, which is infused
Enter in the cathode chamber 1 of electrolyzer with dual membranes and three chambers, intermediate compartment 3 injects the hydrochloric acid solution of 1% mass concentration, the injection of anode chamber 2 1%
The sulfuric acid solution of mass concentration, room temperature (25 degrees centigrade) open electro-deposition of metal copper and tin, the chloride ion that cathode chamber 1 generates
Enter intermediate compartment 3 by anionic ion exchange membrane 4, anode generates oxygen and hydrogen ion, and hydrogen ion is through cation exchange
Film 5 enters intermediate compartment 3, and electrolysis terminates the dissolution work that the hydrochloric acid solution of intermediate compartment 3 is extracted out to reuse to tin copper and iron sediment
Sequence, oxygen are passed through 4 lean electrolyte of embodiment and aoxidize so that solution of ferrous chloride is oxidized to liquor ferri trichloridi, and intermediate compartment 3 is rich
Collect hydrochloric acid, obtain metal copper and tin on cathode plate, tin copper electrodeposition terminates, and extracts 1 lean electrolyte of cathode chamber and centre out respectively
Compartment hydrochloric acid solution is spare;
Embodiment 6
Attached drawing 1-2 is please referred to, takes tin copper and iron sediment obtained by a certain amount of embodiment 1-3, stoichiometrically 1.15 times
Hydrochloric acid (in addition the preferential hydrochloric acid solution using 4 intermediate compartment of embodiment collection 3, insufficient section are added) is added at 95 degrees Celsius
Under the conditions of stirring and dissolving, add pure water be deployed into tin ion mass concentration be 8% stannic chloride copper and iron hydrochloric acid solution, by the solution
It injects in the cathode chamber 1 of electrolyzer with dual membranes and three chambers, intermediate compartment 3 injects the hydrochloric acid solution of 0.8% mass concentration, 2 note of anode chamber
Enter the sulfuric acid solution of 5% mass concentration, room temperature (25 degrees centigrade) opens electro-deposition of metal copper and tin, what cathode chamber 1 generated
Chloride ion enters intermediate compartment 3 by anionic ion exchange membrane 4, and anode generates oxygen and hydrogen ion, hydrogen ion through sun from
Proton exchange 5 enters intermediate compartment 3, and electrolysis terminates to extract out the hydrochloric acid solution of intermediate compartment 3 reuse to tin copper and iron sediment
Dissolution process, the oxygen that anode generates are passed through 4 lean electrolyte of embodiment and aoxidize so that solution of ferrous chloride is oxidized to ferric trichloride
Solution, intermediate compartment 3 are enriched with hydrochloric acid, obtain metal copper and tin on cathode plate, tin copper electrodeposition terminates, and extracts cathode chamber out respectively
1 lean electrolyte and 3 hydrochloric acid solution of intermediate compartment are spare.
In conclusion the invention has the following advantages that
1, the tin copper in tin removal waste liquor is not only efficiently separated out, further to the processing of tin removal waste liquor filtrate, so that moving back tin
Thin stillage recycling has achieved the effect that as new tin stripping liquid;
2, hazardous waste realizes that plant area recycles, and no increment waste liquid outlet is environmentally friendly;
3, the existing etching production method of existing PCB production line is not changed, is easily realized and is promoted;
4, metal copper and tin is recycled by dual membranes and three chambers electrolytic deposition, reduces traditional pyrometallurgical smelting Separation of Tin process for copper pollution
The risk of environment.
The upper only embodiments of the present invention, are not intended to restrict the invention.For those skilled in the art
For, the invention may be variously modified and varied.All any modifications made in spirit and principles of the present invention are equally replaced
It changes, improve, should all be included within scope of the presently claimed invention.