Adsorption of phenthoate and acetochlor from water by clays and organoclays

Article type: Research Article

Authors: LIAO, Min | XIE, Xiao-mei

Affiliations: College of Environmental and Resource Sciences, Department of Resources Science, Zhejiang University, Hangzhou 310029, China

Note: [] Corresponding author. E-mail: [email protected]

Abstract: Adsorption of phenthoate and acetochlor onto kaolin, montmorillonite, bentonite clays and respective organoclays prepared by the exchange of quaternary ammonium as tetradecyltrimethyl ammonium bromide (TTAB), dodecyltrimethylammonium bromide (DTAB), and cetylpyridinium chloride (CPC) were studied. The adsorption equilibrium data points were fitted to Freundlich isotherm equations. The adsorption of phenthoate and acetochlor were significantly enhanced by surfactant treatment of the clays. The amount of both pesticides adsorbed per unit mass of organoclay followed the order of TTA-kaolin < TTA-montmorillonite < TTA-bentonite, which is inconsistent with the organic carbon content of the clays. The removal efficiency of organomontmorillonite to treat acetochlor is in the order of CP(C_{16})-montmorillonite > TTA(C_{14})-montmorillonite > DTA(C_{12})-montmorillonite. Phenthoate is adsorbed to greater extent than acetochlor by each adsorbent, which may be due to the higher hydrophobicity of phenthoate, indicating considerable hydrophobic interaction between adsorbent/adsorbate systems.

Keywords: adsorption, clays, organoclays, phenthoate, acetochlor

Journal: Journal of Environmental Sciences, vol. 16, no. 5, pp. 738-741, 2004