CN87103814A

CN87103814A - Electrolytic process is POV nickel from the nickel plating waste residue

Info

Publication number: CN87103814A
Application number: CN 87103814
Authority: CN
Inventors: 张铨
Original assignee: Individual
Current assignee: Individual
Priority date: 1987-05-23
Filing date: 1987-05-23
Publication date: 1988-12-14

Abstract

A kind of is raw material with the plating waste residue, takes the method for electrolytic process POV nickel.Adopt this method can improve the shortcoming of chemical method, make in the waste residue 5～50% copper be reclaimed by-product metallic copper or copper sponge; The purity height of single nickel salt, copper content≤0.002% (weight) contains nuisance NO ₃ ^-≤ 0.005% (weight); The rate of recovery height of this method nickel, economic benefit is higher.Its technology is that the plating waste residue is made crude nickle sulphate earlier, uses water dissolution, carries out electrolysis, and Cu Lv is deposited on negative electrode, feeds oxygenant and makes Fe  be oxidized to Fe, adds alkali and generates Fe (OH) ₃Precipitation, filtration, crystallization just make single nickel salt.

Description

The present invention uses nickel-contained waste slag, and particularly electroplating nickel-contained waste slag is raw material, takes a kind of method of electrolytic process POV nickel.

Producing of technical pure single nickel salt, the one, by concentration extraction in the electrolyte behind the decopper(ing) of electricity Jie copper work, the 2nd, under oxidizing condition, produce (" Encyclopedia of chemical technology " Vol.9 is P.298) with pure metallic nickel with sulfuric acid reaction.

In the last few years, in order to utilize waste product, domestic beginning was a raw material with the nickel-contained waste slag that Electroplate Factory reclaims, and produced the technical pure single nickel salt.Electroplate Factory's waste residue is mainly taken off by the negative electrode hanger, and its Chemical Composition mainly is a copper except that metallic nickel, and its content is 5～50%, and other has elements such as small additions of chromium, iron.The general chemical method that adopts prepares, promptly earlier with nitric acid and the molten Jie's waste residue of vitriolic mixing acid, make the crude nickle sulphate crystallization, then rough single nickel salt is made solution with water-soluble Jie, add nickelous carbonate or nickel hydroxide its pH value that raises again, or throw nickel powder, sodium sulphite etc., elements such as copper, iron are separated, again after filtration, filtrate is concentrated, crystallization just obtain single nickel salt.There is following shortcoming in this method: account for 5%～50% copper in (1) waste residue and be difficult to reclaim, generally all discard.(2) decopper(ing) poor effect, be difficult to reach≤0.002%.(3) NO ^- ₃Be difficult to remove to≤0.005% NO ^- ₃Existence the quality of nickel plating is had certain harm.(4) hydroxide quantity of Chu Liing is bigger, causes that easily nickel is with Ni(OH) ₂The loss of co-precipitation.

The objective of the invention is fully to reclaim nickel and copper in the nickel plating waste residue, make highly purified single nickel salt and pay product copper, reach the copper content≤0.002%(weight in the product single nickel salt), its nuisance NO ^- ₃Remove to≤0.005%(weight).

Preparation technology of the present invention earlier places retort with nickel-contained waste slag, adds dilute sulphuric acid, divides then for several times to add concentrated nitric acid, and its consumption approximately is a vitriolic 1/5, treat molten Jie of raw material to a certain degree, introduce crystallizer tank and carry out crystallization.

Rough single nickel salt is water-soluble, concentration reaches about Be ' 30 degree, leave standstill, insolubles is in bottom land, clear liquor moved into electrolyzer carry out electricity and be situated between, and anode is a nickel plate or with in nickel plating anode scrap (broken nickel block) frame of packing into, frame can be weaved into titanium bar or batten, also available hard polyvinyl chloride plate weldering system, boring, both are conductor with lead for the back.Negative electrode is a material with copper, stainless steel or titanium.Adjust electrolyte pH value in 0～1.5 scope with sulfuric acid, control electrolyte temperature is in 30～70 ℃ of scopes, with 50～55 ℃ of the bests.Cu in the electrolyte ⁺⁺Be deposited on negative electrode, strengthen cathodic polarization gradually, make the Cu in the electrolyte ⁺⁺Near tracer level, stop electricity and be situated between.With the Fe in air or the hydrogen peroxide oxidation electrolytic solution ⁺⁺Be Fe ⁺⁺⁺, sampling analysis is looked Fe ⁺⁺Oxidation is finished during the nearly vestige of content, and pH value to 4.5～5.5 with nickelous carbonate or nickel hydroxide or liming or dilute sodium hydroxide or barium carbonate rising solution make Fe ⁺⁺⁺Precipitation finishes, after filtering, with filtrate concentrate, crystallization and the product single nickel salt.

A spot of chromium in the nickel-contained waste slag raw material, because of it is insoluble to sulfuric acid and nitric acid when producing rough single nickel salt, the overwhelming majority is sunken to container bottom with fine fragment, and the chromium sheet of denier may be sneaked into electrolytic solution, is filtered when deironing.Minor N O in the electrolytic solution ^- ₃In electrolytic process, can all be reduced into ammonium ion.

Advantage of the present invention is the purity height of the single nickel salt that makes, copper content≤0.002%(weight), NO ^- ₃Can remove to≤0.005%(weight), almost can be with whole NO ^- ₃On negative electrode, be reduced to ammonium ion, ammonium salt have an effect that improves the nickel layer quality.In addition, the present invention can reclaim the form of the copper in the raw material with metallic copper or copper sponge, the rate of recovery height of while single nickel salt, thus improve its economic benefit greatly.

Embodiment:

The nickel-contained waste slag raw material is placed reactor, add dilute sulphuric acid, divide then for several times to add concentrated nitric acid, its consumption approximately is a vitriolic 1/5, treats molten Jie of raw material to a certain degree, and proportion is drawn solution to crystallizer tank and carried out crystallization greater than Be ' 1.4 o'clock.

Get rough single nickel salt crystallization, be situated between to Be ' 30 degree with water-soluble, leave standstill, insolubles is in bottom land, clear liquor is moved into electrolyzer carry out electricity Jie, adjusting electrolyte pH with sulfuric acid is about 1, and electrobath circuit is got the multiple-series formula, cell body can be made with steel plate, Steel Concrete, acid resisting brick, grouan or diabase etc., and first three is planted need and serves as a contrast with flexible PVC or rigid polyvinyl chloride.Anode nickel plate, negative electrode are copper coin.The electrolyte working temperature is at 50～55 ℃, heating mode passes through lead or the heat exchange in intercepting basin or header tank of titanium serpentine tube with steam, make hot electrolyte deliver to each electrolyzer by conduit, its trend get go out under enterprising or under go out on advancing and all can, keep electrolyte circulation, 15～20 liters/minute of the every grooves of flow velocity with acid proof pump.It is 0.5～1A/DM that current density begins ², reducing with copper concentration, current density can be reduced to 0.05A/DM ², finding on negative electrode has gas to produce (H ₂), or Cu in the sampling analysis solution ⁺⁺When content is tracer level, stops electricity and be situated between, at this moment NO ^- ₃All be converted into NH ⁺ ₄The solution that electricity has been situated between moves into the iron removal by oxidation groove, is equipped with H at 70 ℃ of left and right sides bubbling airs ₂O ₂Oxidation is Fe wherein ⁺⁺Be Fe ⁺⁺⁺, sampling analysis is looked Fe ⁺⁺Can stop oxidation during the nearly vestige of content.Add NiCO ₃About rising pH value to 5, continue to use pneumatic blending, precipitation of hydroxide occurs, after filtration, filtrate enters concentration tank, is concentrated into Be ' 45～50 degree, and the immigration crystallisation chamber is carried out crystallization and is product, recording the nickeliferous of product is 20.6%(weight), iron content is a 0.002%(weight), contain NO ^- ₃Be 0.005%, cupric is a 0.002%(weight).

Claims

1, a kind of preparation method of single nickel salt is a raw material with the nickel-contained waste slag, makes rough single nickel salt earlier, it is characterized in that adopting electric Jie's method refining, and rough single nickel salt is water-soluble, leaves standstill solution, and insolubles is sunken to the end, clear liquor is carried out electricity be situated between the Cu in the electrolyte ⁺⁺Be deposited on negative electrode, strengthen cathodic polarization gradually, make the Cu in the electrolyte ⁺⁺Stop electricity when approaching tracer level and be situated between, the feeding oxygenant makes the Fe in the electrolyte ⁺⁺Be oxidized to Fe ⁺⁺⁺, the Fe in solution ⁺⁺During for tracer level, oxidation is finished, and adds alkali or basic salt and improves its pH value, Fe (OH) occurs ₃Throw out, after filtration, filtrate is concentrated, crystallization goes out single nickel salt.

2, according to the single nickel salt preparation method of claim 1, it is characterized in that dielectric anode is that frame can be weaved into titanium bar or batten, or is welded into hard polyvinyl chloride plate in nickel plate or nickel plating anode scrap (nickel fragment) frame of packing into, boring, both are conductor with lead for the back.

3,, it is characterized in that dielectric cathode material is copper or stainless steel or titanium according to the single nickel salt preparation method of claim 1.

4,, it is characterized in that electrolyte pH value transfers to 0～1.5 with sulfuric acid, with pH=1 the best according to the single nickel salt preparation method of claim 1.

5,, it is characterized in that the oxygenant that adds after electricity has been situated between is air and hydrogen peroxide according to the single nickel salt preparation method of claim 1.

6, according to the preparation method of the single nickel salt of claim 1, the alkali or the salt that it is characterized in that improving after oxidation is finished pH are nickelous carbonate or nickel hydroxide or liming or dilute sodium hydroxide or barium carbonate, and add-on is that pH reaches till 4.5～6.