Molding of Molecular Sieve Residues and Their Application in Cleaning Oily Wastewater

Abstract

To deeply clean oily wastewater, molecular sieve residues (MSRs) were sufficiently recycled and utilized due to their high specific surface area, porous structure, and outstanding adsorption property. Molding MSRs (MMSRs) were prepared by adding additives (starch, citric acid, and soluble glass) to MSRs and were then filled into a fixed bed for adsorbing and separating the oil in wastewater. Sodium dodecylbenzenesulfonate was used to modify the MMSRs, and their adsorption property was also investigated. In addition, the MSRs were characterized by scanning electron microscopy, energy-dispersive X-ray spectroscopy, Brunauer–Emmett–Teller analysis, and Fourier transform infrared spectroscopy. The results indicated that MMSRs satisfied the filling requirement of fixed bed, and their dynamic adsorption capacity could reach 0.1854\xa0mg\xa0g−1. Furthermore, the static adsorption capacity of MMSRs achieved 1.7346\xa0mg\xa0g−1 in the optimum conditions, and the oil adsorption performance of modified MMSRs was further enhanced. Therefore, this work suggests that MSRs are promising alternatives in cleaning oily wastewater.