Synthesis and utilization of an amidoxime surfactant as a collector in the flotation separation of azurite from quartz and calcite

Abstract

In this paper, a new amidoxime compound, p-methylphenylethyl amidoxime (PEBH), was synthesized, and its flotation mechanism for separating azurite from quartz and calcite was studied. The results of flotation experiments showed that when the pH was 11 and the dosage of PEBH was 2.5 × 10⁻⁴ mol/L, the recovery and grade of azurite reached 94.32 % and 37.45 %, respectively. In contrast, the recovery of quartz is 11.97 %, and the grade is only 18.83 %. The recovery rate of calcite is 19.10 %, and the grade is only 2.54 %. Zeta test results show that the surface potential shift of azurite after PEBH treatment is much larger than that of quartz and calcite. It also proves that PEBH has a strong adsorption effect on the surface of azurite, while the adsorption effect on the surface of quartz and calcite is weak. XPS analysis results show that Cu²⁺ is the active site of PEBH adsorbed on the surface of azurite, and a stable five-membered chelating ring structure is formed after interaction. However, this obvious interaction did not occur on the surface of quartz and calcite. At the same time, the SEM-EDS test results also confirmed this view. Therefore, PEBH has the characteristics of high selectivity as a collector for azurite, making it a promising collector in the field of azurite flotation, providing a new choice for copper oxide recovery.