Finely Dispersed Micro- and Nano-Gold Recovery Using Thermomorphic Polymer with Diphenylphosphine

Abstract

The article reports test data on adsorption and flotation characteristics of thermomorphic polymer joined with diphenylphosphine—TMPD. The test materials are natural pyrite and arsenopyrite, and models of gold-bearing sulfide minerals. Electron microscopy and X-ray structure analysis prove that reductive adsorption of gold at the surface of sulfide minerals from HAuCl₄ solution allows modeling natural aggregates of sulfides and finely dispersed gold. UV spectrophotometry proves selective adsorption of TMPD at gold. Laser scanning microscopy shows connection of TMPD with micro- and nano-size gold on polished sections of pyrite and arsenopyrite. During monomineral flotation, joint use of TMPD and butyl xanthate at a ratio of 1:1 doubles the yield of gold-bearing sulfides and enables maximum recovery of gold minerals at the total consumption of reagents reduced by 30–50%. It is found that TMPD is selective relative to gold-bearing minerals and its combination with xanthate ensures a considerable increment in gold-bearing mineral recovery by flotation.