CN102586617A

CN102586617A - Method for recovering gold from iodine-potassium iodide leachate

Info

Publication number: CN102586617A
Application number: CN2012100328271A
Authority: CN
Inventors: 宋小年; 和德路; 苏武; 李武京
Original assignee: 771 Research Institute of 9th Academy of CASC
Current assignee: 771 Research Institute of 9th Academy of CASC
Priority date: 2012-02-14
Filing date: 2012-02-14
Publication date: 2012-07-18
Anticipated expiration: 2032-02-14
Also published as: CN102586617B

Abstract

The invention discloses a method for recovering gold from iodine-potassium iodide leachate. Concentrated sulfuric acid (H2SO4) and hydrogen peroxide are added into the leachate containing iodine, potassium iodide and gold iodide, the two reagents are reacted with iodine ions in the leachate to generate iodine, the iodine is volatilized out of a container at high temperature, and after the iodine is volatilized, the leachate is transparent; and the leachate is continuously heated, the two reagents also can convert gold in an ion state into gold in an atomic state to fulfill the aim of reducing the gold, and excessive reagents are decomposed at high temperature. The invention aims to control the types and weight of the added chemicals, simplify the operating process and improve the purity of the recovered gold; and by the method, the utilization rate of the gold can be greatly improved.

Description

The recovery method of gold in the IKI gold leachate

Technical field:

The invention belongs to the recovery field of gold in the gold-containing scrap, invention relates to the recovery method of gold in a kind of IKI gold leachate.

Background technology:

At present, the recovery method of gold has zinc replacement, sodium sulphite anhydrous 99.3 reduction method, gac/bubble to mould absorption method and strike etc. in the IKI gold leachate.Owing to contain a large amount of iodine (7%) and potassiumiodide (15%) in the immersion liquid, the treatment process to it is to add acid (hydrochloric acid, nitric acid, hydrogen peroxide) or tin protochloride earlier to remove the iodine in the immersion liquid usually, and then adding reductive agent or reclaim gold out with high temperature sintering.

Li Guichun ^[1]Recovery method Deng to gold in the gold leachate has carried out intensive research; Result of study shows: from the iodate gold leachate, reclaim gold, the zinc substitution method is feasible in theory, but the consumption of zinc is greater than cyaniding system consumption zinc; Consider from economic aspect, be inappropriate for iodination and reclaim gold; With the method for activated carbon adsorption, the absorption recovery of gold can reach more than 93%, but negatively charged ion has certain influence to the adsorption activity of activated carbon in the gold leachate, and this method is applicable to the gold leachate of low iodide ion concentration; Strike reclaims gold, and the starting point concentration of gold should be greater than 40mg/L in the gold leachate, and the electrolytic deposition recovery of gold can reach more than 95%, but gold concentration when low (＜40mg/L), the recovery of one-step electrolysis gold is lower, and this is difficult to reach in practical application; Use SO ₂, NaHSO ₃, Na ₂SO ₅Also can reclaim the gold in the gold leachate Deng the acidic reduction agent.

Zhou Yongyi ^[2]In " leaching golden method ", propose, add reductive agent, make gold form complex compound, precipitate the gold in the gold leachate at last with the iodo-iodide solution.

The method of more than extracting gold all can be extracted gold preferably, and the recovery is higher, but because the chemical reagent or other raw material that add are more, has a strong impact on the purity of extracting gold, and complicated operating process is difficult to carry out large-scale production in addition.

The method that more than reclaims gold all can be extracted gold preferably, and the recovery is higher, but because the chemical reagent or other raw material that add are more, has a strong impact on the purity of extracting gold, and complicated operating process is difficult to carry out large-scale production in addition.

Summary of the invention:

The objective of the invention is to control the kind and the weight of adding chemical, simplify the operation course, improve the purity that reclaims gold; In the past, because the consumption of gold leachate is few, useless gold leachate is arbitrarily toppled over discharging, along with the high speed development of unicircuit, the consumption of gold leachate constantly increases, and of the present invention coming into operation can be improved the utilization ratio of gold greatly.

Contain iodine, potassiumiodide and gold triiodide in the gold leachate, in gold leachate, add the vitriol oil (H ₂SO ₄), two kinds of reagent of hydrogen peroxide, iodide ion reaction generates iodine in above-mentioned two kinds of reagent and the gold leachate, iodine volatilizes container under action of high temperature, after the iodine volatilization in the immersion liquid was accomplished, immersion liquid was transparent; Continue heating, above-mentioned two kinds of reagent can be converted into the gold of ionic state the gold of atomic state again, realize the purpose of reduction gold, and unnecessary reagent decomposes under action of high temperature.

The invention has the beneficial effects as follows:

Because present method only adds the higher vitriol oil of purity and hydrogen peroxide agent; Dilution, bath water are pure water in the removal process; Method is not introduced other too much impurity; So it is high that present method reclaims the purity of gold, the purity that adopts present method to reclaim gold is carried out plasma emission spectrometry (ICP-OES) measure, it is as shown in table 1 to record the result.Measure the result and reach 99.99%, reclaim gold and can be recycled and reused among the unicircuit production technique; Present method adopts chemical reagent reduction gold, after the gold reduction, and the complete water white transparency of immersion liquid, filtrating does not have the golden ability of dissolving again, so the recovery of present method almost can reach 100%; In addition, present method operating process is simple, and experimental installation is few, can be used for reclaiming in the technology on a large scale.

The ICP-OES that table 1 reclaims gold measures result (wt%)

Element term	Ag	Cu	Fe	Pb	Bi	Sb	Summation
								Measured value	0.0031	0.000013	0.00054	0.00033	Do not detect	/	0.0040
Desired value	0.005	0.002	0.002	0.001	0.002	0.001	0.01

Embodiment:

Get a certain amount of gold leachate, put into open container, add the vitriol oil (H with gold leachate equivalent ₂SO ₄) reagent and the hydrogen peroxide agent of partly measuring, heating is along with the rising of gold leachate temperature; Iodide ion is reduced to iodine; Iodine in reductive iodine and the liquid is from container with purple smoke form volatilization, and purple smoke disappears, and liquid shows during for water white transparency and drives the iodine end of processing; Continue to be heated to 350 ℃, decompose the unnecessary vitriol oil (H ₂SO ₄) and hydrogen peroxide, vessel port stops heating when bringing out existing white smoke, and cooling vessel is to room temperature; Slowly add a spot of pure water dilution gold leachate along the container wall, filter with ashless filter paper, with the pure water washing filter residue of heat to neutral; The oven dry filter residue; Heating makes the filter paper charing, and in 800 ℃ of calcination filter residues 1 hour, filter residue was proof gold.

Because present method also can be used as gold content measuring method in the gold leachate, adopt present method that 13 bottles of gold leachates are carried out the gold content analysis, analytical results is as shown in the table.

The mensuration result of gold content in 13 bottles of gold leachates of table 2

Numbering	Gold Content (grams per liter)	Numbering	Gold Content (grams per liter)
				1#	2.78	8#	6.99
2#	2.46	9#	6.92
				3#	7.44	10#	7.37
4#	5.60	11#	4.16
				5#	3.53	12#	0.93
6#	4.45	13#	6.01
				7#	4.37	/	/

Reference:

[1] Li Guichun, Ji Shoufeng, Wang Huiping. when soaking gold, iodate proposes gold and iodine renovation process research [J] from leach liquor. mining metallurgical engineering, 2006,26 (3): 42-47.

[2] Zhou Yongyi. leach the method [J] of gold with the iodo-iodide solution. coloured mining and metallurgy, 1994 the 03rd phases.

Claims

1. the recovery method of gold in the IKI gold leachate is characterized in that, comprises the steps:

1) gets a certain amount of said gold leachate and put into container, add the vitriol oil (H with gold leachate equivalent ₂SO ₄) reagent and the hydrogen peroxide agent of partly measuring;

2) heat said gold leachate, make iodide ion be reduced to iodine, with the volatilization of purple smoke form, purple smoke disappears the iodine in reductive iodine and the liquid, when liquid is water white transparency, drives the iodine end of processing from container;

3) continue heating, decompose the unnecessary vitriol oil (H ₂SO ₄) and hydrogen peroxide, vessel port stops heating when bringing out existing white smoke, and cooling vessel is to room temperature;

4) add pure water dilution gold leachate, and to the liquid filtering after the dilution; To neutral, dried filter residue and calcination filter residue 1 hour with the filter residue behind the pure water washing and filtering of heat, filter residue is proof gold.

2. method according to claim 1 is characterized in that: continue to be heated to 350 ℃ in the said step 3).

3. method according to claim 1 and 2 is characterized in that: the temperature during calcination filter residue in the said step 4) is 800 ℃.

4. method according to claim 1 and 2 is characterized in that: adopt the liquid after ashless filter paper filters dilution in the said step 4).