CN-121653364-B - Environment-friendly gold leaching agent and gold leaching method

Abstract

The invention relates to an environment-friendly gold leaching agent and a gold leaching method, belonging to the technical field of gold leaching. The gold leaching agent provided by the invention has good gold leaching effect, high gold selectivity, no traditional virulent sodium cyanide, little environmental pollution and environmental protection.

Inventors

• CHEN JIANHUA
• CHEN YUANLIN

Assignees

• 广西大学

Dates

Publication Date

20260508

Application Date

20260203

Claims (5)

1. 1. The environment-friendly gold leaching agent is characterized by comprising sodium thiocyanate and guanidine salt, wherein the guanidine salt comprises guanidine isothiocyanate and guanidine hydrochloride, the mass ratio of the sodium thiocyanate to the guanidine salt is (3-5): 1, and the mass ratio of the guanidine isothiocyanate to the guanidine hydrochloride is (0.5-1).
2. 2. A gold leaching method based on the environment-friendly gold leaching agent as claimed in claim 1, which is characterized by comprising the following steps: and mixing the gold-containing sample, the environment-friendly gold leaching agent and water, and reacting to leach gold, wherein the pH value of the solution in the reaction system is 7-12.
3. 3. The gold leaching method according to claim 2, wherein the reaction temperature is 10-50 ℃.
4. 4. The gold leaching method according to claim 2, wherein the concentration of the environment-friendly gold leaching agent in the solution of the reaction system is 0.1-5wt%.
5. 5. The gold leaching method according to claim 2, wherein the gold-containing sample comprises at least one of gold ore, gold smelting slag.

Description

Environment-friendly gold leaching agent and gold leaching method Technical Field The invention relates to the technical field of gold leaching, in particular to an environment-friendly gold leaching agent and a gold leaching method. Background Gold is an important financial reserve and has wide application in the fields of electronic communication, medicine, aerospace and the like. Wet leaching is a main method for extracting gold from gold ore resources and gold-containing secondary resources, wherein the cyanide gold leaching technology has a dominant role for a long time due to high leaching efficiency and strong adaptability. Cyanide is highly toxic, however, and the safety risk of production and transportation is high, and the cost of tailings/tailings disposal is high, forcing industry to develop safer, green gold leaching systems. To reduce the environmental and safety risks of gold leaching processes, various non-cyanide gold leaching agent systems, such as thiosulfate systems, thiourea systems, chloride systems, etc., have been proposed in the prior art. The non-cyanide system can realize complexing and dissolving of gold under certain conditions, but has the common problems in engineering application, such as (1) potential toxicity hazards or potential environmental risks of partial gold leaching agents or auxiliary agents, difficulty in meeting the green requirements of higher standards, (2) sensitivity to ore types, ore pulp pH, oxidation-reduction potential and impurity ions, insufficient stability in the leaching process, high medicament cost, and (3) slower complexing dynamics, poor selectivity, strong dissolution of metals such as copper/iron and the like, poor suitability of subsequent extraction Jin Liucheng (such as activated carbon adsorption, displacement or electrodeposition) and the like. The factors restrict the large-scale popularization and application of the environment-friendly gold leaching agent. Therefore, development of an environment-friendly gold leaching agent which has low toxicity/low harm, high leaching efficiency, stable system and compatibility with the existing gold extraction process is needed to meet the technical requirements of green development of gold ores and clean recovery of gold-containing secondary resources. Disclosure of Invention In order to solve the technical problems, the invention provides an environment-friendly gold leaching agent which has an excellent leaching effect on gold elements, does not contain sodium cyanide, has little environmental pollution and is environment-friendly. In order to achieve the above object, the technical scheme of the present invention is as follows: An environment-friendly gold leaching agent comprises sodium tripolycyanate and guanidine salt. In some embodiments, the mass ratio of sodium thiocyanate to guanidine salt is 1 (0.1-1). In some embodiments, the guanidine salt includes at least one of guanidine isothiocyanate, guanidine hydrochloride. In some embodiments, the guanidine salt includes guanidine isothiocyanate and guanidine hydrochloride. In some embodiments, the mass ratio of the guanidine isothiocyanate to the guanidine hydrochloride is 1 (0.5-1). The invention also provides a method for leaching gold by using the environment-friendly gold leaching agent in any embodiment, which comprises the following steps: And mixing the gold-containing sample, the environment-friendly gold leaching agent and water, and carrying out a reaction to leach gold. In some embodiments, the reaction temperature is 10-50 ℃, preferably 20-30 ℃. In some embodiments, the concentration of the environmentally friendly gold leaching agent in the solution of the reaction system is 0.1-5wt%, preferably, the concentration of the gold leaching agent is 0.1-2wt%. In some embodiments, the pH of the reaction system is 7-12. In some embodiments, the gold-containing sample comprises at least one of gold ore, gold smelting slag. In some embodiments, the method comprises the steps of: S1, adding water into a gold-containing sample, grinding into ore pulp, and then adjusting the pH value to 7-12; s2, adding the environment-friendly gold leaching agent into ore pulp, and carrying out a reaction to leach gold for 8-48 hours to obtain gold-containing solution. In some embodiments, the pulp concentration is 20 to 80wt%. Compared with the prior art, the invention has the following beneficial effects: The environment-friendly gold leaching agent provided by the invention has the advantages of high gold leaching rate, high speed, high stability in the use process, strong adaptability to the pulp environment and capability of being used under neutral to alkaline conditions. In addition, the gold leaching agent has high selectivity to gold, and the leaching solution obtained after leaching the gold-containing sample has low content of metal impurities obtained by the subsequent gold extraction process. In addition, the gold leaching agent consists of sodiu