阅读说明：本技术 一种复杂难浸金矿的强化浸出方法 (Enhanced leaching method of complex refractory gold ore ) 是由 柯柏友 于 2021-06-25 设计创作，主要内容包括：本发明公开了一种复杂难浸金矿的强化浸出方法,涉及贵金属冶金领域。对高硫高砷含碳复杂难浸金矿在浸出前先进行强化预处理,添加具有氧化能力及强的催化氧化剂和活化剂配合氢氧化钠(NaOH)进行强化预处理。由于催化氧化剂及活化剂的强化氧化作用,在常温、常压下引发砷硫矿物在高温、高压下才能发生的氧化反应,使难浸金矿包裹体氧化解离裸露,使“劫金”的碳失去活性而不再“劫金”。再用常规的方法浸出提金,从而达到比较高的浸出率,浸出时间缩短50％以上,从而获得较好的经济效益。(The invention discloses a method for strengthening leaching of complex refractory gold ores, and relates to the field of precious metal metallurgy. Before leaching, the high-sulfur high-arsenic carbon-containing complex refractory gold ore is subjected to strengthening pretreatment, and a catalytic oxidant and an activating agent with strong oxidizing ability are added to be matched with sodium hydroxide (NaOH) for strengthening pretreatment. Because of the enhanced oxidation action of the catalytic oxidant and the activator, the oxidation reaction of the arsenic-sulfur mineral at high temperature and high pressure is initiated at normal temperature and normal pressure, so that the refractory gold ore inclusion is oxidized, dissociated and exposed, and the carbon of the gold robbing is inactivated and the gold robbing is not carried out any more. The gold extraction is carried out by using a conventional method, so that the higher leaching rate is achieved, the leaching time is shortened by more than 50%, and the better economic benefit is obtained.)

1. An enhanced leaching method of complex refractory gold ore is characterized in that: the high-sulfur high-arsenic carbon-containing complex refractory gold ore is pretreated before leaching, and is added with a catalytic oxidant with oxidation function and strong catalytic oxidizer and an activator to be matched with sodium hydroxide (NaOH) for strengthening pretreatment. Because of the enhanced oxidation action of the catalytic oxidant and the activator, the oxidation reaction of the arsenic-sulfur mineral at high temperature and high pressure is initiated at normal temperature and normal pressure, so that the refractory gold ore inclusion is oxidized, dissociated and exposed, and the carbon of the gold robbing is inactivated and the gold robbing is not carried out any more. The gold extraction is carried out by using a conventional method, so that the higher leaching rate is achieved, the leaching time is shortened by more than 50%, and the better economic benefit is obtained.

2. The method for the enhanced leaching of the complex refractory gold ore of claim 1, wherein: the catalytic oxidant is A, B component, and the component A is composed of persulfate, which can be at least one of ammonium persulfate, sodium persulfate and potassium persulfate.

3. The method for the enhanced leaching of the complex refractory gold ore according to claims 1-2, wherein: the catalytic oxidant is divided into A, B components, and the B component consists of peroxide: can be at least one of sodium peroxide, potassium peroxide, calcium peroxide, sodium percarbonate, urea peroxide, boron peroxide, barium peroxide and hydrogen peroxide.

4. The method for the enhanced leaching of the complex refractory gold ore according to claims 1 to 3, wherein: the catalytic oxidant is divided into A, B components, and the components are as follows: a and B are 10: 2-3 (W/W).

5. The method for the enhanced leaching of the complex refractory gold ore of claim 1, wherein: the activator consists of a halogen compound: sodium fluoride, sodium chlorate, sodium hypochlorite, organic chlorides such as at least one of dichloroisocyanuric acid, trichloroisocyanuric acid, chloramine, dichloramine, chlorobromoisocyanuric acid, bromine, sodium bromide, and sodium bromate.

6. The method for the enhanced leaching of the complex refractory gold ore of claim 1, wherein: the addition amount of the catalytic oxidant is 0.5-5 kg per ton of mineral during pretreatment.

7. The method for the enhanced leaching of the complex refractory gold ore of claim 1, wherein: the addition amount of the mineral activating agent is 0.2-2 kg per ton during pretreatment.

Technical Field

The invention belongs to the field of metal hydrometallurgy, and relates to a method for strengthening leaching of complex refractory gold ores.

Background

Along with the rapid development of the socioeconomic and large-scale mining development of China, the resource of the easily-treated gold ore is increasingly reduced or exhausted, the complex and difficultly-treated gold ore becomes the main resource of gold production, according to statistics, more than 60% of the gold reserves in the world are the difficultly-treated gold ore, 1/3 in the current global gold yield is from the difficultly-treated gold ore, the reasonable, efficient and environment-friendly development and utilization of the difficultly-treated gold ore resource becomes the main technical problem facing all gold producing countries in the world at present, and in China, the proportion of the difficultly-treated gold ore resource occupying the reserved reserves is always maintained at about 1/3, so the processing of the difficultly-treated gold ore resource is necessary to face most of gold mines, which is also the key problem of the sustainable development of the gold industry in China at present.

Complex refractory gold ores are generally divided into 3 types: firstly, micro-fine particle gold ore exists in the form of micro or sub-micro, even crystal lattice, monomer dissociation is difficult to achieve only by grinding ore, gold is difficult to contact with leachate, and conventional cyanidation is difficult to leach; secondly, carbonaceous gold ore is generally clay mineral with high carbon content, the phenomenon of cyaniding to robbe gold is serious, and the gold leaching rate is low; and the polymetallic complex gold ore has the characteristics of complex composition and variable property. Such as sulfur, arsenic, antimony and the like, which can consume cyanide and oxygen in the cyaniding process, and compounds formed by conductive minerals such as tellurium, bismuth, antimony and the like and gold dissolve and passivate the cathode of the gold, so that the leaching of the gold is hindered, the extraction of gold and silver by cyaniding is seriously interfered, and the treatment is difficult. A great deal of research is carried out by a plurality of scholars on the utilization of the gold mine resource which is difficult to treat, and great progress is made. Along with the application of technologies such as high-pressure pre-oxidation, biological pre-oxidation, roasting pre-oxidation and the like in the gold extraction of complex and difficult-to-treat gold ores, the development and the utilization of the complex and difficult-to-treat gold ores are increasingly wide, but the problems of low extraction rate of valuable metals, large investment of production equipment, long production period, high production cost and the like still exist.

Disclosure of Invention

In order to solve the defects in the prior art, the method for strengthening leaching of the complex refractory gold ore is characterized by comprising the following steps: the high-sulfur high-arsenic carbon-containing complex refractory gold ore is pretreated before leaching, and is added with a catalytic oxidant with oxidation function and strong catalytic oxidizer and an activator to be matched with sodium hydroxide (NaOH) for strengthening pretreatment. Because of the enhanced oxidation action of the catalytic oxidant and the activator, the oxidation reaction of the arsenic-sulfur mineral at high temperature and high pressure is initiated at normal temperature and normal pressure, so that the refractory gold ore inclusion is oxidized, dissociated and exposed, and the carbon of the gold robbing is inactivated and the gold robbing is not carried out any more. The gold extraction is carried out by using a conventional method, so that the leaching rate of gold minerals containing 20-35% of sulfur, 5-36% of arsenic, 1-3% of antimony and 1-8% of carbon is improved to 85-98% from less than 10-30% of the conventional cyanidation leaching rate, a higher leaching rate is achieved, the leaching time is shortened by 50-70%, and the complex refractory gold ores are not too refractory. The defects of the prior art are well overcome, and the leaching of the complex refractory gold concentrate obtains better economic benefit. The method has great positive significance for resource utilization of the high-sulfur, high-arsenic and high-carbon complex refractory gold concentrate.

According to the enhanced leaching method for the complex refractory gold ore, the catalytic oxidant is A, B components, the A component is composed of persulfate, and can be at least one of ammonium persulfate, sodium persulfate and potassium persulfate. The component B consists of peroxide: can be at least one of sodium peroxide, potassium peroxide, calcium peroxide, sodium percarbonate, urea peroxide, boron peroxide, barium peroxide and hydrogen peroxide.

The patent relates to an enhanced leaching method of complex refractory gold ores, wherein A, B components of catalytic oxidant comprise the following components in percentage by weight: a and B are 10: 2-3 (W/W).

The patent relates to an enhanced leaching method of complex refractory gold ore, wherein an activating agent is composed of halogen compounds: sodium fluoride, sodium chlorate, sodium hypochlorite, organic chlorides such as at least one of dichloroisocyanuric acid, trichloroisocyanuric acid, chloramine, dichloramine, chlorobromoisocyanuric acid, bromine, sodium bromide, and sodium bromate.

The patent relates to a method for strengthening leaching of complex refractory gold ores, wherein the addition amount of a catalytic oxidant of each ton of ores is 0.5-5 kg during pretreatment.

The patent relates to a method for strengthening leaching of complex refractory gold ores, wherein the addition amount of an activating agent for each ton of ores is 0.2-2 kg during pretreatment.

Persulfate is a common oxidant and has been widely applied in various fields. Begin to be used as a dry cleaning bleaching agent; the monomer polymerization initiator is applied to organic synthesis of polytetrafluoroethylene, polyvinyl chloride, polystyrene, chloroprene rubber and the like in 50 years; in the 70 s, the metal surface cleaning agent is used as a printed circuit board and a metal surface treatment micro-etching agent for cleaning metal surfaces. At present, persulfate is applied to various industries such as textile, food, photography, storage batteries, grease, oil exploitation, cosmetics and the like. Persulfate is applied to environmental pollution treatment, and is a new field recently developed abroad. Persulfate activation becomes a novel advanced oxidation technology, and related research in the field is lacked at present.

The persulfate is ionized in water to generate persulfate ionsIts standard oxidation-reduction potential E⁰Up to +2.01V, close to ozone E⁰+2.07V, greater than permanganate radical E⁰+1.68V and hydrogen peroxide E⁰+ 1.70V. The molecule contains peroxy (-O-O-), which is a strong oxidant. Under the condition of activation and excitation, the peroxy (-O-O-) bond is broken and solidifiedCan be activated and decomposed into sulfate radicalAnd the oxidation-reduction potential of the OH-of the hydroxyl free radical is as high as 2.6-3.1V, and the hydroxyl free radical has extremely strong electron obtaining capability, namely oxidation capability, so that most of pollutants in water can be oxidized and degraded.

The activator peroxide is a compound containing a peroxy group (-O-). Can be used as hydrogen peroxide derivative, and is characterized by containing peroxide ions in the molecule. Peroxides are strong oxidizers and can react with water to form the corresponding hydroxide and oxygen. Peroxides are divided into inorganic peroxides and organic peroxides. Peroxides play an important role in the textile industry, bleaching industry.

The main reason for the complex refractory gold ore is that the ore contains high sulfur, arsenic, antimony, carbon and the like, and the harmful mineral exists in the gold ore in the form of sulfide and forms tight package on gold. The invention adds catalytic oxidant and activator to match with sodium hydroxide (NaOH), and carries out strengthening pretreatment at normal temperature and normal pressure, and under the strengthening action of the catalytic oxidant and the activator, oxidation reaction of sulfur, arsenic, antimony, carbon and the like is carried out to generate arsenous acid, thioarsenous acid, antimonous acid, thioantimonic acid or polysulfide of arsenic and antimony which are easy to dissolve in water. Thereby removing sulfur, arsenic and antimony from the gold minerals. The inclusion is oxidized and dissociated, the gold is exposed or semi-exposed, carbon in the mineral is oxidized in the oxidation process to lose the gold robbing capacity, and the gold is extracted by a conventional method, so that the complex refractory gold ore becomes less refractory. The defects of the prior art are well overcome, and the leaching of the complex refractory gold concentrate obtains better economic benefit. The method has great positive significance for resource utilization of the high-sulfur, high-arsenic and high-carbon complex refractory gold ore.

Detailed Description

The specific implementation mode of the reinforced leaching method of the complex refractory gold ore comprises the following steps: 1. grinding the complex refractory gold ore to 200-300 meshes; 2. adding 0.5-5 kg of catalytic oxidant, 0.2-2 kg of activator and 5-150 kg of sodium hydroxide (NaOH) per ton of ore; 3. the liquid-solid ratio is 2: 1, and the mixture is stirred in a stirring barrel for 12 to 24 hours under the normal temperature and pressure state, so that the strengthening pretreatment is realized. 4. After the pretreatment is finished, adjusting the pH value to 11-12 by lime, adding a gold extracting agent and active carbon, and performing conventional gold extraction to realize high-efficiency gold extraction of complex refractory gold ores.

Example 1

The gold concentrate of Guizhou Xingyi gold has the average gold grade of 86 g/t, 6g/t, 15.3 percent of arsenic content, 35.9 percent of sulfur content, 2.6 percent of carbon content, 85 percent of gold concentrate with the granularity of-200 meshes, 15 to 25 percent of gold leaching rate and 72 hours of leaching time in conventional cyanidation leaching. Adopting catalytic enhanced leaching, carrying out enhanced pretreatment for 24 hours before leaching by using 75 kilograms of alkali (NaOH) per ton of ore, 4 kilograms of catalytic oxidant per ton of ore and 2 kilograms of activating agent per ton of ore, adjusting the pH value to 12 by lime, adding 12 kilograms of environment-friendly metal extraction agent per ton of ore, and leaching for 12 hours, wherein the leaching rate reaches 95.46%.

Example 2

Certain gold concentrate of Burma is complex and difficult-to-leach gold concentrate, the gold grade is 36.3g/t, 30.1 percent of sulfur is contained, 22.7 percent of arsenic is contained, gold exists in sulfide in a microscopic or sub-microscopic level or even in a lattice form, conventional cyaniding leaching is carried out, and the gold leaching rate is about 10 percent. Adopting catalytic oxidation to enhance leaching, adding 105 kg/ton of caustic soda flakes (NaOH), 5 kg/ton of catalytic oxidant and 2 kg/ton of activator into a vertical stirring mill together, grinding until the powder accounts for 90 percent of minus 300 meshes, carrying out enhanced pretreatment for 12 hours, adjusting the pH value to 12 by lime, adding 8 kg/ton of environment-friendly metal extraction agent of Fufang brand, and leaching for 12 hours, wherein the leaching rate reaches 89.96 percent. And better economic benefit and social benefit are obtained. Bringing good news to the mine.

Example 3

Some gold concentrate of Gansu Longnan, gold 52.9g/t, silver 26.73g/t, antimony 3.21%, carbon 8.13%, sulfur 21.4%, arsenic 5.3%; the gold leaching rate is about 15 percent by using the conventional cyanidation leaching. Adopting catalytic oxidation enhanced leaching, adding 25 kg/ton of caustic soda flakes (NaOH), 3 kg/ton of catalytic oxidant and 1.5 kg/ton of activator into a vertical stirring mill together, further milling until the content of minus 300 meshes is 90%, carrying out enhanced pretreatment for 12h, adjusting the pH value to 12 with lime, adding 11 kg/ton of environment-friendly metal extraction agent of Fufang brand, and leaching for 12h, wherein the leaching rate is 96.43%. The more satisfactory effect is obtained.

In summary, the preferred embodiments of the present invention are described above, but the scope of the present invention is not limited thereto, and any person skilled in the art should be considered to be within the scope of the present invention, and equivalents and modifications of the technical solutions and concepts of the present invention should be included in the scope of the present invention.