Control of porous size distribution on solvent-free mesoporous carbon and their use as a superadsorbent for 17α-ethinylestradiol removal

Abstract

This work reports the synthesis of mesoporous carbon using the solvent-free soft template method and their application for the adsorption of the emerging contaminant 17α-ethinylestradiol. For the first time, for the flexible solvent-free method, we evaluated how the precursor carbon/surfactant ratio (p/s), heating rate, stabilization time and self-assembly temperature, can influence textural properties of the materials. According to the results, the carbon source/surfactant ratio was the one which influenced textural characteristics most. The materials synthesized in p/s-1 had a smaller medium pore diameter (3.4 nm) while materials synthesized in p/s-0.5 showed an average diameter of larger pores (4.9 nm). Transmission micrographs indicated the formation of two types of pore ordering: wormholes and honeycombs. However, despite some differences in pore ordering, all materials showed textural quality. We found that the adsorption of 17α-ethinylestradiol is more affected by the diameter, volume and mesoporous content than by the type of pore ordering. Thus, materials with a high diameter and mesoporous content showed 99% removal with a maximum adsorption capacity of 157 mg/g. Also, the adsorption capacity of the material remained almost 100% until the fourth cycle and above 85% until the tenth cycle.