Synthesis of porous carbon materials from water hyacinth via hydrothermal carbonization assisted chemical activation for carbon-based electrode applications

Abstract

Recently, lignocellulosic materials have been widely utilized as feedstocks for several applications such as carbon, biofuels and biochemical productions because of their potentials (i.e. waste reduction, carbon sequestration, renewable). In this study, porous carbon was successfully synthesized from water hyacinth (WHs) via hydrothermal carbonization assisted with chemical activation using Na2CO3 and K2CO3. The hydrothermal carbonization process was studied in the range of 160-200°C for 4-12h and the hydrothermal chars were then further pyrolyzed under a supply of N2 flow 100ml/min at 700-900°C for 2h. The as-pyrolyzed chars were then activated by two different bases including Na2CO3 and K2CO3 at the ratio of 1.0 (w/w, hydrothermal char: chemical) to obtain highly porous carbon. The results indicated that carbon percentage, surface area and porous structure were improved with the higher hydrothermal temperature showing the best results at 180°C for 8h. Moreover, the development of pore structure of WHs porous carbon was successfully by chemical activation with K2CO3.