Eco-Friendly Remediation of Adsorbed Chlorsulfuron Herbicide via Walnut Shells Derived Activated Carbon

Document Type: Research Article

Author

Fatima Jinnah Women University, Rawalpindi, Pakistan

Abstract

Chlorsulfuron (1-(2-chlorophenyl) sulfonyl-3(4-methoxy-6-methyle-1,3,5-triazin-2-yl)) is the primary commercialized sulfonylurea weedicide aimed at combating several leafy weeds for protection of many cereals and potato crop. It is used a pre as well as a post emergent weedicide. Due to its organic ringed structure, it poses serious environmental degradation particular in lithospheric compartment. Present investigation has analyzed its adsorptive interactions with soils inherently composed of unique physicochemical attributes. In a batch equilibrium experiment, sample 2 expressed highest adsorption coefficient Kd(ads) with an overall adsorption spanning over a range of 6.78 to 39.85 µg/mL. Adsorptive capacity analysis via Linear and Freundlich models yielded R2 > 0.8 indicative of best fitting of these models to Chlorsulfuron adsorption. Statistical analysis showed negative correlation of soil pH and Kd(ads) (R2= -0.85) and positive correlation with organic matter (R2= 0.96). The data was further analyzed by univariate ANOVA and its accuracy was checked through residual plots. Furthermore, the adsorbed Chlorsulfuron was remediated via green method by utilization of walnut shells derived activated carbon in varied concentrations of 5 ppm and 7.5 ppm of Chlorsulfuron. Highest removal in 5 ppm was observed in soil 9 (85%) while in 7 ppm highest removal was observed in soil 2 (91%). Current investigation not only explored the adsorptive pattern of Chlorsulfuron but also developed a nontoxic, ecofriendly, pragmatic and economical adsorbent for its removal.

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