Study On Distribution Behavior Of Selenium And Tellurium In Copper Matte Synergistic Smelting

Copper matte synergistic smelting process adopts copper matte as collector to concentrate the rare metals in electronic waste.In the treatment,Al₂O₃,SiO₂,CaO and Mg O were fed into the slag to realize rapid enrichment of valuable metals and seperation of impurities.However,the distribution behavior of Selenium and tellurium in the synergistic treatment has not been clarified.In this study,the distribution behavior of selenium and tellurium under different slag systems,sulfur potentials and oxygen potentials was investigated by thermodynamic calculation and experimental work.It provides the theoretical guidance on the directional enrichment of Se and Te in the synergistic treatment.The main conclusions are shown as follows:（1）Phase equilibrium between the matte and the slag with different compostions（FeO_X-SiO₂、FeO_X-SiO₂-Al₂O₃、FeO_X-SiO₂-CaO、FeO_X-SiO₂-Mg O、FeO_X-SiO₂-Al₂O₃-5%CaO、FeO_X-SiO₂-Al₂O₃-10%CaO）was stuided by high temperature isothermal equilibration technique followed by rapid quenching.Based on the analysis results of SEM-EDS and EPMA,a three-phase equilibrium of matte-slag-tridymite was found in all samples.（2）The results of the experiments employing the binary slags（FeO_X-SiO₂）showed that the distribution coefficients of Cu between the matte and the slag decreased from 150 to 125 with increasement of the matte grade,whereas the distribution coefficients of Fe between the matte and the slag were all less than 1.The distribution coefficients of Se and Te between the matte and the slag increased with the matte grade.A higher matte grade was favorable for Se and Te to deport to the matte phase.（3）The results of the experiments employing the ternary slags（FeO_X-SiO₂-Al₂O₃、FeO_X-SiO₂-CaO、FeO_X-SiO₂-Mg O）showed that 5%Al₂O₃was not favorable for the Se and Te enrichment in the matte phase,CaO was beneficial to Se enrichment in the matte phase,Mg O was beneficial to Te enrichment in the matte phase at low grade.（4）The results of the experiments employing the slags（FeO_X-SiO₂-Al₂O₃-CaO）showed that the distribution coefficients of Cu between the matte and the slag with 10%CaO,5%Al₂O₃ increased from 150-180 to190-300 with the matte grade lower than 70%,that the distribution coefficients of Se between the matte and the slag with 5%CaO,5%Al₂O₃was the highest.Pictures 78;Tables 32;References 125.