Metal-organic framework-derived carbons: Preparation from ZIF-8 and application in the adsorptive removal of sulfamethoxazole from water

Abstract In this study, we prepared highly porous carbonaceous materials from a metal-organic framework (MOF), ZIF-8, by pyrolysis. Pyrolysis temperature had a significant effect on the porosity of MOF-derived carbons (MDCs); the MDCs obtained at 1000 °C (MDC-1000) exhibited the highest surface area and pore volume. The MDC-1000 showed almost twice the porosity of the original ZIF-8 used to prepare it. The obtained MDC was applied to the adsorptive removal of a pharmaceutical product [sulfamethoxazole (SMX)] from water, and the adsorption amount on MDC was 20 times higher than that on the original ZIF-8. Moreover, a very high adsorption for SMX was exhibited by the prepared MDC, in fact, the best ever reported for any adsorbent. Plausible adsorption mechanisms, such as H-bonding, could be suggested based on the effect of the solution pH on the status and adsorbed quantity of SMX and the zeta potential of MDC. Moreover, MDC-1000 and SMX acted as the H-donor and H-acceptor, respectively, in the mechanism (H-bonding) for adsorption. MDC can be a potential adsorbent for the removal of SMX because of its high adsorption capacity and ready recyclability.