Remarkable adsorbent for removal of bisphenol A and S from water: Porous carbon derived from melamine/polyaniline

Recently, contamination of water resources with various organics such as bisphenols is a problem worldwide. Here, we developed nitrogen-enriched porous carbons (N-PDCs) from pyrolysis of melamine-loaded polyaniline (PANI), for the first time. The N-PDCs and PANI-derived carbons (PDCs, without using melamine) were characterized and applied in adsorptive removal of two typical bisphenols, such as bisphenol A and S (BPA and BPS, respectively), from water under a wide range of conditions. Via this research, we found that one N-PDC (N-PDC-700, obtained at 700 °C) showed very remarkable performances in adsorption of BPA (Q0: 961 mg/g) and BPS (Q0: 971 mg/g) under pH of 7.0. In other words, N-PDC-700 has Q0 value for BPS around 2 times as much as that of the most effective adsorbent, MIL-101-NH2. Moreover, the Q0 value of N-PDC-700 for BPA is the second highest, after the sp2 C dominant N-doped carbon. The plausible adsorption mechanism could be suggested based on the adsorption of BPA under a wide range of pH values. Finally, the N-PDC-700 was easily recycled for several uses, suggesting the potential application in adsorption of bisphenols from water.