Facile and economical synthesis of porous activated semi-cokes for highly efficient and fast removal of microcystin-LR.

Abstract To mitigate the threat of microcystins on the environment and human health, we demonstrate for the first time that porous activated semi-cokes (ASCs) with average pore diameters of 2–20 nm could be used as adsorbents for the fast and efficient removal of microcystin-LR (MC-LR). The surface physicochemical properties of ASCs were carefully investigated and their relations with the adsorption performance were discussed. The results showed that ASCs activated by HNO 3 and KOH exhibited excellent adsorption capacities of 4276 and 8430 μg/g, respectively, which were nearly 5 times and 10 times higher than that of activated carbon (AC). ASCs also showed a fast adsorption property by over 95% recovery of MC-LR in the initial 10 min. The overall adsorption of MC-LR on ASCs might be dominated by both external diffusion and intra-particle diffusion. In addition, ASCs manifested an outstanding reusability and the adsorption of MC-LR was hardly influenced by the coexisting fulvic acid at low concentration. Given the remarkable performance and low cost, activated semi-cokes are expected to present promising potentials for the practical application in removing microcystins from aqueous solutions.