(480a) Application of Waste Hay-Derived Biochar for Adsorption of Cyanobacterial Toxin in Water

The biochar-driven adsorption of microcystin was investigated as a promising remediation technology. The objective of present study is to investigate alfalfa-derived biochars (AF biochars) for adsorption of microcystin-LR (MC-LR) in water for the first time. The relationships between properties of AF biochars produced at various temperatures (350-650^oC) and adsorption capacities of MC-LR were evaluated using a statistical analysis. The pyrolysis temperature led to a highly increase in surface area, aromaticity, and adsorption capacity of MC-LR. Among the AF biochars, AF650 had much higher adsorption capacity for MC-LR because of mechanisms such as electrostatic, π-π, and hydrophobic interactions supported by its positively charged surface, high BET surface area, and high hydrophobicity. The adsorption kinetic and isotherm models fitted pseudo-second order and Langmuir for MC-LR onto AF650, respectively. The AF650 possessed highly adsorption capacity for MC-LR but lower adsorption capacity than those of activated carbon.