Use of Surface Modified Silica gel factory Waste for Removal of 2,4-D Pesticide from Agricultural Wastewater: A case study

Abstract

The silica gel waste (SGW), after its collection from a local factory (Kolkata, India) was modified with cationic surfactant and was utilized as an adsorbing media for the removal of 2,4- dichlorophenoxyacetic acid (2,4-D) from agricultural runoff of a tea garden. Characterization of base adsorbent and modified adsorbent was carried out. The efficacy of the adsorbent was evaluated through both batch and fixed bed mode. Kinetics and isotherm study were conducted and the parameters were compared with 2,4-D bearing distilled water samples. The values of diffusion coefficients were determined. Presence of electrolyte and solution pH was found to affect the performance of the adsorbent significantly. The removal efficiency of surfactant modified silica gel waste (SMSGW) in case of wastewater was found to be lower than the 2,4-D bearing distilled water sample. The data of column run was analyzed using Logit model. Batch desorption study was carried out using ethanol and acetone. The studies revealed surfactant coated SGW to be an efficient adsorbing media for 2,4-D removal.