Clean utilization of waste oil: Soap collectors prepared by alkaline hydrolysis for fluorite flotation

Abstract An innovative approach of clean utilization of waste oil is proposed to reduce the risk of environmental pollution and achieve cleaner production of fluorite. The waste oil in kitchen waste was first separated from solid waste and waste water. Further, alkaline hydrolysis was succeeded in preparing soap collectors by saponification reaction. Further, the fluorite flotation was conducted to verify the applicability of the renewable collectors. The results of FT-IR show that the characteristic peaks of the renewable collector appear on the particle surface after the adsorption treatment, which indicates that the collector can be effectively adsorbed. Effect of renewable collector on the charge properties of fluorite surface was analyzed and results show that the electronegativity of particle surface is enhanced after adsorption, which indicates that chemisorption can occur under alkaline conditions. The flotation test results show that the renewable collector has excellent separation effect on fluorite. The flotation kinetic analysis indicates that the four kinetic models have ideal applicability for describing the flotation behavior of renewable collectors for fluorite. The research results reveal the optimistic prospect of harmful waste oil transformation into collectors, and have potential industrial application prospects.