Removal of pesticide residues by mesoporous alumina from water

Abstract

Water decontamination through adsorption is regarded as an effective technique for pesticide remediation. Mesoporous alumina synthesized by autoclaving technique was evaluated for adsorption of 43 pesticides from water. The pesticide removal by adsorption was optimised by addition of each pesticide @ 500 µg/L of water and treatment with mesoporous alumina @ 4 g/L for 30 min. Quantitative analysis of pesticides in water was done by GC-MS/MS and LC-MS/MS. Maximum adsorption for individual pesticide was 95.7%, 68.3% and 52.1% in de-ionised, ground and waste water, respectively. Pesticides belonging to synthetic pyrethroids (SP), neonicotinoids, organophosphates (OP) and triazole groups were removed preferentially, but the organochlorine (OC) insecticides were less or not adsorbed at all. Average removal of pesticides was lowest in waste water (25.2%) compared to ground (37.4%) and de-ionised (66.1%) water. The study indicated the prospect of using mesoporous alumina for removal of pesticides to produce potable water.