阅读说明：本技术 一种原矿中富集贵金属的选矿方法 (Beneficiation method for enriching precious metals in raw ores ) 是由 梁波 于 2020-04-26 设计创作，主要内容包括：一种原矿中富集贵金属的选矿方法,包括如下步骤：(1)在原矿粉中加入自来水,然后加入浓硫酸和氧化剂,搅拌2h,进行固液分离,得到含贵金属矿渣和液体；(2)将步骤(1)中得到的液体经氢氧化钠水解沉降,收集沉淀物；(3)将步骤(1)得到矿渣中边搅拌边依次加入工业级硝酸、溴化钠、氧化剂；(4)加入盐酸、氯酸钠、氯化钠、次氯酸钠和双氧水,待反应液的电位为670mV,pH值为0-0.5时,再继续搅拌；(5)进行固液分离,弃去矿渣,得到澄清含贵金属的液体,继续加热到80℃,加8％硫化钠溶液,调pH值,搅拌2h,收集沉淀物,沉淀物用浓盐酸水解,收集水解后的黑色沉淀物；(6)除杂,酸洗,先稀盐酸、再稀硫酸搅拌冲洗,过滤,干燥,得到贵金属粉末。(A beneficiation method for enriching precious metals in raw ores comprises the following steps: (1) adding tap water into raw ore powder, then adding concentrated sulfuric acid and an oxidant, stirring for 2 hours, and carrying out solid-liquid separation to obtain slag and liquid containing precious metals; (2) hydrolyzing and settling the liquid obtained in the step (1) by using sodium hydroxide, and collecting precipitates; (3) sequentially adding industrial nitric acid, sodium bromide and an oxidant into the slag obtained in the step (1) while stirring; (4) adding hydrochloric acid, sodium chlorate, sodium chloride, sodium hypochlorite and hydrogen peroxide, and continuing stirring when the potential of the reaction liquid is 670mV and the pH value is 0-0.5; (5) performing solid-liquid separation, removing slag to obtain clear liquid containing precious metals, continuously heating to 80 ℃, adding 8% sodium sulfide solution, adjusting the pH value, stirring for 2 hours, collecting precipitate, hydrolyzing the precipitate with concentrated hydrochloric acid, and collecting hydrolyzed black precipitate; (6) removing impurities, pickling, stirring and washing with dilute hydrochloric acid and dilute sulfuric acid, filtering, and drying to obtain noble metal powder.)

1. A beneficiation method for enriching precious metals in raw ores is characterized by comprising the following steps:

(1) crushing raw ore by a crusher to obtain raw ore powder, adding tap water into the raw ore powder, uniformly stirring, adding concentrated sulfuric acid and an oxidant while stirring, stirring for 2 hours, and performing solid-liquid separation by using a plate press to obtain slag containing precious metals and liquid containing base metals;

(2) hydrolyzing the liquid containing base metals obtained in the step (1) by sodium hydroxide, settling, adjusting the pH to 8, collecting precipitates, namely the base metals, and recycling water;

(3) adding tap water into the slag containing the noble metals obtained in the step (1), wherein the liquid-solid ratio is 5: 1, sequentially adding industrial nitric acid, sodium bromide and an oxidant while stirring, and stirring for 30min at the reaction temperature of 45-55 ℃;

(4) continuously adding hydrochloric acid, sodium chlorate, sodium chloride, sodium hypochlorite and hydrogen peroxide while stirring, and continuously stirring for 6 hours when the potential of the reaction liquid is 670mV and the pH value is 0-0.5;

(5) performing solid-liquid separation, removing slag to obtain clear liquid containing precious metals, continuously heating to 80 ℃, adding 8% sodium sulfide solution while stirring, adding sodium hydroxide to adjust the pH value to 9.0, stirring at 80 ℃ for 2 hours, collecting precipitate, hydrolyzing the precipitate with concentrated hydrochloric acid, adjusting the pH value to-0.5, and collecting hydrolyzed black precipitate;

(6) removing impurities from the black precipitate obtained in the step (5), pickling, stirring and washing with dilute hydrochloric acid and dilute sulfuric acid, performing vacuum filtration on the mixture to obtain 400-mesh powder, wherein the drying temperature is not more than 120 ℃, and thus obtaining the noble metal powder.

2. The beneficiation method for precious metal enrichment of raw ore according to claim 1, wherein the particle size of the raw ore powder in the step (1) is 200 mesh.

3. The beneficiation method for enriching precious metals from raw ore according to claim 1, wherein the liquid-solid ratio of tap water to raw ore powder in step (1) is 3 to 5: 1.

4. the beneficiation method for enriching precious metals from raw ores according to claim 1, wherein the addition amount of the concentrated sulfuric acid in the step (1) is 10 to 20L/ton of raw ore, and the oxidant is hydrogen peroxide, and the addition amount is 3L/ton of raw ore.

5. The beneficiation method for precious metal enrichment of raw ore according to claim 1, wherein the addition amount of industrial-grade nitric acid in the step (3) is 10L g/ton of raw ore, the addition amount of sodium bromide is 5 kg/ton of raw ore, and the oxidant is potassium permanganate, the addition amount of which is 40-50 g/ton of raw ore.

6. The beneficiation method for enriching precious metals from raw ores according to claim 1, wherein the addition amount of hydrochloric acid in the step (4) is 5L/ton of raw ore, the addition amount of sodium chlorate is 5 kg/ton of raw ore, the addition amount of sodium chloride is 3-5 kg/ton of raw ore, the addition amount of sodium hypochlorite is 4L/ton of raw ore, and the addition amount of hydrogen peroxide is 3L/ton of raw ore.

7. A beneficiation method according to precious metal concentration in raw ore according to claim 1, wherein the rotation speed of the stirring in the step (4) is 65r/min, and the temperature is 80 ℃.

8. The beneficiation method for enriching precious metals from raw ores according to claim 1, wherein the concentration of the dilute hydrochloric acid and the dilute sulfuric acid in the step (6) is 6M.

Technical Field

The invention belongs to the technical field of beneficiation process optimization, and particularly relates to a beneficiation method for enriching precious metals in raw ores.

Background

Noble metals are important materials in national defense industry, are mainly used in the fields of aerospace, aviation, missiles, rockets, micro-electricity technology and the like, and are known as 'modern new metals' and 'vitamins in modern metal industry'. According to statistics, the precious metal reserves of main countries in the world are distributed as follows: south africa 89.26%, usa 1.18%, russia 9.08%, canada 0.42%, others 0.06%.

At present, the methods for "enriching" and refining precious metals are reported mainly as follows:

firstly, crushing, screening, gravity separation, flotation, magnetic separation, combined separation and composite separation, and aims to 'enrich'.

And secondly, soaking and boiling by concentrated sulfuric acid at the temperature of 180-190 ℃, washing residues after chlorination of the treated object by 10 times of water after boiling, introducing few noble metals into the solution and storing the noble metals in the residues, and then performing chlorination treatment to enrich the residues.

Thirdly, sulfation roasting-leaching at the temperature of 500-650 ℃, and leaching the roasted product by using dilute sulfuric acid, which has the advantage that almost all platinum groups are left in the leaching slag except for the volatilization of osmium tetroxide.

Fourthly, leaching chlorine gas into three types: 1. and (3) medium-temperature chloridizing roasting and leaching one by one: with the proviso that the platinum group content is 250-340 g/t; leaching the roasted product with dilute hydrochloric acid at 500 ℃ and 600 ℃ to obtain platinum group concentrate. 2. And (4) liquefying and leaching the aqueous solution. 3. Sodium chlorate or sodium hypochlorite replaces chlorine to generate nascent chlorine in liquid to achieve the aim of chlorination, and the processing object is platinum group concentrate.

Fifthly, the medium temperature of 500 ℃ is not enough and the mixture is burnt to high temperature, so that the metal is gasified and recovered, namely, the gasification and enrichment are carried out.

And sixthly, the cyanidation method is used for easily dissolving platinum group metals like gold dissolution, has poor effect, is used for production, but has serious damage to the environment.

Disclosure of Invention

The invention provides a beneficiation method for enriching precious metals in raw ores, which aims to solve the problems of high cost, low enrichment and serious ecological damage of the conventional beneficiation method.

The technical scheme provided by the invention is as follows:

a beneficiation method for enriching precious metals in raw ores comprises the following steps:

(1) crushing raw ore by a crusher to obtain raw ore powder, adding tap water into the raw ore powder, uniformly stirring, adding concentrated sulfuric acid and an oxidant while stirring, stirring for 2 hours, and performing solid-liquid separation by using a plate press to obtain slag containing precious metals and liquid containing base metals;

(2) hydrolyzing the liquid containing base metals obtained in the step (1) by sodium hydroxide, settling, adjusting the pH to 8, collecting precipitates, namely the base metals, and recycling water;

(3) adding tap water into the slag containing the noble metals obtained in the step (1), wherein the liquid-solid ratio is 5: 1, sequentially adding industrial nitric acid, sodium bromide and an oxidant while stirring, and stirring for 30min at the reaction temperature of 45-55 ℃;

(4) continuously adding hydrochloric acid, sodium chlorate, sodium chloride, sodium hypochlorite and hydrogen peroxide while stirring, and continuously stirring for 6 hours when the potential of the reaction liquid is 670mV and the pH value is 0-0.5;

(5) performing solid-liquid separation, removing slag to obtain clear liquid containing precious metals, continuously heating to 80 ℃, adding 8% sodium sulfide solution while stirring, adding sodium hydroxide to adjust the pH value to 9.0, stirring at 80 ℃ for 2 hours, collecting precipitate, hydrolyzing the precipitate with concentrated hydrochloric acid, adjusting the pH value to-0.5, and collecting hydrolyzed black precipitate;

(6) removing impurities from the black precipitate obtained in the step (5), pickling, stirring and washing with dilute hydrochloric acid and dilute sulfuric acid, performing vacuum filtration on the mixture to obtain 400-mesh powder, wherein the drying temperature is not more than 120 ℃, and thus obtaining the noble metal powder.

Preferably, the particle size of raw ore powder in step (1) is 200 meshes.

Preferably, the liquid-solid ratio of tap water to raw ore powder in the step (1) is 3-5: 1.

preferably, the adding amount of the concentrated sulfuric acid in the step (1) is 10-20L/ton of raw ore, and the oxidant is hydrogen peroxide, and the adding amount of the hydrogen peroxide is 3L/ton of raw ore.

Preferably, the addition amount of the industrial-grade nitric acid in the step (3) is 10L/ton of raw ore, the addition amount of the sodium bromide is 5 kg/ton of raw ore, and the addition amount of the oxidizing agent is 40-50 g/ton of raw ore.

Preferably, the addition amount of the hydrochloric acid in the step (4) is 5L/ton of raw ore, the addition amount of the sodium chlorate is 5 kg/ton of raw ore, the addition amount of the sodium chloride is 3-5 kg/ton of raw ore, the addition amount of the sodium hypochlorite is 4L/ton of raw ore, and the addition amount of the hydrogen peroxide is 3L/ton of raw ore.

Preferably, the rotation speed of stirring in the step (4) is 65r/min, and the temperature is 80 ℃.

Preferably, the concentration of the dilute hydrochloric acid and the dilute sulfuric acid in the step (6) is 6M.

Compared with the prior art, the invention has the beneficial effects that:

the beneficiation method for enriching the precious metals in the raw ores has the advantages of low cost, good enrichment and less damage to the environment, and solves the problem of difficult precious metal recovery caused by the problems of high sulfur, high arsenic, high carbon, complex mineral properties and the like.

Detailed Description

The present invention will be more readily understood by reference to the following examples, which are given without limiting the scope of the invention.