Application of nanoporous ceramic membrane derived from Fe/S/Si/Al/O-rich mining solid waste in oil–water separation and heavy metal removal of industrial high concentrated emulsifying wastewater

Abstract

Ceramic membranes are widely used in industrial wastewater treatment due to their excellent chemical stability, thermal stability, high oil cut-off rate, and long-term recyclability. However, its application range is limited because of the high price of commercial ceramic membranes. In this study, a low-cost environment-oriented ceramic membrane was prepared from gold mine tailings and SiO2-rich granite waste slag by sintering method. The Fe/S/Si/Al/O enriched ceramic membrane prepared by sintering in an atmospheric atmosphere was beneficial to the application of oil–water separation and heavy metal removal of industrial high concentrated emulsifying wastewater. At lower sintering temperature (1000 ℃), adding 33.3% gold tailings (M3), the membrane had good oil cut-off performance (96.1%) and stability. 29.47 MPa mechanical strength and 2.75% mass loss of 1000-M3 was confirmed under extreme acidic and alkaline conditions, and even in high-temperature environments, the mass loss was only 2.5%. After 16 cycles of performance test, the oil cut-off rate only decreased by 0.01%. The developed membrane exhibited good chemical stability and thermal stability. Based on the analysis of membrane contamination behavior, the ceramic membranes prepared could restore nanoporous channels only by ultrasonic treatment. In addition, 100% removal performance of iron and copper was obtained, and 78.6% removal efficiency was achieved for Chromium and cadmium. These fascinating characteristics make the novel ceramic membrane an excellent candidate with a high oil–water separation ability. More importantly, the inexpensive materials from recyclable solid waste and low-energy consumption preparation technique make it possible to scale up production. Thus, the as-prepared nanoporous ceramic membrane prepared from gold mine tailings with biological toxicity as hazardous waste has the potential of waste resource utilization for treating industrial grade high load emulsion wastewater.