Natural and Anthopogenic Carbonaceous Materials for the Remediation of Polychlorinated Biphenyls from Aqueous Solution

The presence of polychlorinated biphenyls (PCBs) in the environment is a continuing challenge that presents a hazard to ecosystems and human health. The proliferation of carbon-based nanomaterials such as graphene (GE) and carbon nanotubes (CNT) has generated interest in their use as sorbent materials for the remediation of PCBs. In this study, isotherm experiments were conducted to compare the sorption of 11 PCB congeners to activated carbon (AC), black carbon (BC), GE and CNT. The Langmuir, Freundlich and Polanyi-Dubinin-Manes models were used to fit the experimental data, resulting in model parameters and distribution coefficients. AC exhibited the highest sorption of the materials tested, with average distribution coefficients 1.0, 1.5 and 2.5 orders of magnitude greater than GE, CNT and BC, respectively. Although improvements can be made to the nanomaterials, in the present study, AC proved to be the superior sorbent for PCBs in solution followed by GE and CNT.