Method for refining and enriching element gold by utilizing selenium ether

Abstract

The invention discloses a method for refining and enriching element gold by utilizing selenium ether, and relates to the technical field of refining and enrichment of precious metal elements. According to the method, an isocyanate, a selenium-containing small molecule compound, a cross-linking agent and a tin-containing catalyst are utilized to prepare a selenium-containing porous material, or a selenium-containing polymer is prepared by using the isocyanate, the selenium-containing small molecule compound and the tin-containing catalyst; the selenium-containing porous material or the selenium-containing polymer is immersed in an aqueous solution containing free-state element gold to stand until the element gold is completely precipitated; and the selenium-containing porous material or theselenium-containing high molecule on the surface of the precipitated element gold is removed, and a refined and enriched gold elementary substance is obtained. According to the method, based on the interaction between the reducing property and coordination of the element selenium, the selenium-containing porous material is prepared by adopting different material synthesis methods while the molecular structure of the selenium-containing small molecule compound is adjusted. A prepared material can realize environment-friendly, efficient, and high-selectivity reduction and enrichment on free element gold in multi-metal ion component electronic waste water.

Description

technical field [0001] The invention relates to the technical field of refining and enriching precious metal elements, in particular to a method for refining and enriching gold elements by using selenium ether. Background technique [0002] Gold is a powerful but extremely rare metal, with only 190,000 tons of gold being mined so far. With the development of the third industrial revolution, gold plays an indispensable role in the field of electronic equipment due to its extremely low resistivity, high ductility, good malleability, and excellent corrosion resistance. However, traditional gold alchemy requires a series of complex processes such as ore grinding, physical separation, and amalgamation treatment, and the gold obtained from mining 1 ton of gold mines can only be used to manufacture about 40 mobile phones. Under the contradiction between high demand and low supply, in 2015, the European Union defined gold as a "key raw material", which indicates that gold will beco...

AI Technical Summary

Problems solved by technology

The former will produce highly toxic cyanide waste liquid during the treatment process, which is more harmful to the environment; the latter needs to use a large amount of organic solvents during the operation process, and the post-treatment is more cumbersome

Not only that, electronic waste contains a large amount of copper and nickel elements, which greatly interferes with the extraction process of gold elements

In the face of existing problems, researchers around the world have carried out a series of explorations - in 2016, the J.Fraser Stoddart research group of Northwestern University reported the work of α-cyclodextrin separation of gold ions, which has good selectivity and environmental friendliness However, the separated gold element is still in a high valence state, and further reduction treatment is required to obtain the gold element; in 2018, the Weedy L.Queen research group of the Swiss Federal Institute of Technology in Lausanne realized the selection of low-concentration gold elements through MOF / polyaniline composite materials However, the preparation process of such materials is complex and powdery solid, which makes it difficult to achieve large-scale production; in April 2019, Tang Benzhong's research group at South China University of Technology invented a polyselenourea enrichment recovery solution Gold ion method (application number: 201910309311.9), with good selectivity and adsorption capacity

However, polyselenurea is a powdery solid with complex synthesis process, and there are great difficulties in practical application; the coordination effect of selenourea structure on gold elements has not been proved and recognized by the academic community; in addition, the thermodynamics of selenourea structure is not Stable, easy to decompose under the condition of light and heat to produce toxic nitrogen oxides and selenide gases, which will cause great harm to the environment and operators

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