Adsorption of Fenitrothion and Methidathion from Aqueous Solution by Tea Industry-Waste

Tea industry-waste refers to the residual solid material produced by extracting tea polyphenols and instant tea from teas. The feasibility of this biomaterial waste for the adsorption of organophosphorous pesticides fenitrothion and methidathion from aqueous solution was investigated. The adsorption capacity of fenitrothion and methidathion onto tea industry-waste increased significantly with the increasing of contact time and the initial concentration of the pesticide. The adsorption capacity of tea industry-waste on fenitrothion was significantly higher than methidathion mainly due to the lower water solubility and higher Log K_ow of fenitrothion. Even the adsorption capacity of methidathion was much lower than that of fenitrothion onto tea industry-waste, it was 2-fold as that caused by commercial activated carbon as reported in the literature. The adsorption capacity of fenitrothion onto tea industry-waste was almost pH independent at the acidic water solution ranged pH 2–7. The data obtained from this test implied that tea industry-waste might be a potential adsorbent for use to the removal of organophosphorous pesticides from water.