Synthesis of trimethylacetyl thiobenzamide and its flotation separation performance of galena from sphalerite

Abstract

A novel surfactant trimethylacetyl thiobenzamide (TTBA) was synthesized and first conducted as flotation separation collector for galena and sphalerite. The flotation performance of TTBA and traditional collector sodium isobutyl xanthate (SIBX) was investigated by micro-flotation, which displayed that TTBA possessed stronger collecting ability than SIBX for galena, as well as better selectivity than SIBX for sphalerite. Zeta potential tests indicated that TTBA possessed superior selectivity to adsorb onto galena surfaces against sphalerite surfaces. FTIR and XPS results showed that TTBA chemisorbed onto galena surfaces with the formation of new chemical bonds. However, before and after treatment by TTBA, there was no obvious change on sphalerite surfaces, indicating no chemisorption occurred. DFT calculations revealed that C = S and C = O groups were the main reaction sites of TTBA, meanwhile, TTBA adsorbed onto galena surfaces by the formation of Pb-S and Pb-O bonds.