Analysis of the Mechanism of Choline Chloride-oxalate Action on Zinc Oxide Leaching Based on First Principles

This is an article in the field of metallurgical engineering. In order to explore the leaching mechanism of zinc oxide from zinc-containing dust by choline chloride and oxalic acid, the interaction of choline chloride and oxalic acid with 1∶1 and 1∶2 eutectic solvent on zinc oxide surface was simulated by means of quantum mechanics, and the simulation results were verified by experiments. The results show that the intermolecular hydrogen bond formed by choline chloride and oxalic acid plays an important role in the stability of eutectic solvent. Ch⁺ gains electrons, OA and Cl^- lose electrons. ZnO(001) surface is the complete cleavage surface of zinc oxide, oxygen and zinc atoms form tetrahedral structure, oxygen atom is easy to gain electrons and zinc atom is easy to lose electrons during the reaction with the outside world. The zinc oxide loses electrons during the interaction between cholinergic chloride-oxalic acid and zinc oxide, and cholinergic chloride-oxalic acid gains electrons. The interaction energy △E=-819.6896Ha between ChCl-2OA and ZnO is small, indicating that zinc oxide is more likely to react with ChCl-2OA. The radial distribution function shows that the chemical adsorption is the main factor in the interaction between choline chloride and oxalic acid and zinc oxide, and the physical adsorption is the secondary factor. The contribution of Cl-Zn formed by chemical adsorption is greater than that of O-Zn. Through the pure mineral test, it can be verified that ChCl-2OA has a better leaching effect on zinc oxide, which verifies the accuracy of molecular simulation of the interaction mechanism between choline chloride and oxalic acid and zinc oxide, and provides a theoretical basis for the leaching of zinc-containing dust with eutectic solvent.