Multi-stage batch adsorption of acephate onto cauliflower like Fe3O4-MMT: Characterization and statistical optimization using response surface methodology

Abstract

Globally acephate (an organophosphate pesticide) contaminates water bodies, and detriment to the biota is cancer-causing and neurotoxic which needs to be safely removed. This study presents the synthesis and characterization of magnetic montmorillonite (Fe₃O₄-MMT) as an adsorbent for the adsorption of acephate. The features and characteristics of the nanocomposite were traced by XRD, SEM-EDX, gas sorption analysis, FTIR, and XRF. RSM techniques were used to identify the optimal process variables that result in the highest removal. The numerical optimization of optimum variables corresponds to an initial acephate concentration of 2 mg/L, pH 6 and material adsorbent dose of 0.5 g/L. The uptake of acephate achieved 83.18 % under optimum environs. Dual factors i.e., concentration and dosage remarked as vital parameters that affected the response from ANOVA. Results revealed that equilibrium adsorption data were best fitted with Langmuir and kinetic data were well described by pseudo-first order kinetic model. Thermodynamic parameters such as enthalpy, entropy and Gibb’s energy were evaluated and the effect of temperature on acephate adsorption was studied. Greater acephate adsorption onto on Fe₃O₄ serves as an excellent material for pesticide mitigation.