(593d) Effect of Surfactant on HTL Derived Hydrochar Physicochemical Characteristics

Porous carbon (POC) is a versatile material that can be used in various applications such as carbon capture, hydrogen storage, soil amendment, wastewater treatment, energy storage and more. Lignocellulosic biomass (LCB) is a useful, abundant and environmentally friendly feedstock as compared to fossilized feedstocks to produce POC. Thermochemical conversion of LCB via hydrothermal liquefaction (HTL) can be employed to obtain hydrochar. Typically, the hydrochar exhibits poor physicochemical characteristics, which needs activation steps to improve specific surface area (SSA), pore volume and a desirable pore size. Superior physicochemical characteristics are desirable for adsorption and energy storage purposes. Although several chemical agents, such as H₃PO₄, ZnCl₂, and KOH known to improve physicochemical characteristics of hydrochar, the effect of surfactants during the chemical activation step is not available. In this study, HTL-derived hydrochar from corn stover was chemically activated with KOH in presence of a surfactant and thermally treated to obtain POC. Three different surfactants, namely Pluronic F127 (non-ionic), cetyltrimethylammonium bromide (CTAB, cationic) and sodium dodecyl sulfate (anionic) were used at different weight ratios during the chemical activation step to study their effects on the characteristics of the derived biochar. It was then thermally treated for 1 hour under constant flow of UHP N₂ gas and acid washed further with 0.1M HCl to obtain POC. These POC samples were characterized by Brunauer-Emmett-Teller (BET) surface area analyzer, Fourier transform infrared (FTIR) spectroscopy, and scanning electron microscopy (SEM). Synthesis and characterization of POC will be presented.