A simple method to prepare carbon-based mesoporous materials by coal gasification of fine slag and its application in phenol adsorption

Phenol is a common organic pollutant that is difficult to degrade and widely exists in all kinds of wastewater. In this study, an economical and environmentally friendly alternative process for phenol-containing wastewater has been developed using porous nano-adsorption material (PNAM) prepared from coal gasification fine slag. The morphology, crystal structure, surface functional groups, gap structure, and specific surface area of PNAM were characterized by SEM, XRD, FT-IR, and BET. The effects of adsorbent dosage, temperature, pH, and reaction time on adsorption were further investigated. In addition, the adsorption kinetics, thermodynamics, and adsorption mechanism were explored. The results show that the surface area of PNAM is high, up to 602 m2 g-1, and the pore volume is 0.507 cm3 g-1. Adsorption processes mainly occur in mesopores between 2 and 5 nm, including physical and chemical adsorption, and here chemical adsorption plays a significant role. The adsorption rate of phenol in a 1000 mg l-1 simulated phenol solution by PNAM reaches 96.14%, while the unit adsorption capacity is 32.045 mg g-1. As a result, it is expected that employing coal gasification fine slag to prepare adsorption materials for phenol-containing wastewater treatment may be an economically feasible and environmentally sustainable strategy.