Sorption of low levels of nonionic and anionic surfactants on soil: effects on sorption of triticonazole fungicide

✍ Scribed by Beigel, Claude; Barriuso, Enrique; Calvet, Raoul

• Publisher: John Wiley and Sons
• Year: 1998
• Tongue: English
• Weight: 245 KB
• Volume: 54
• Category: Article
• ISSN: 1526-498X
• DOI: 10.1002/(sici)1096-9063(199809)54:1<52::aid-ps779>3.0.co;2-z

✦ Synopsis

The sorption of two anionic surfactants and a series of seven nonionic alkylphenolethoxylate surfactants of increasing hydrophilic/lipophilic balance (HLB) in a loamy clay soil was evaluated. The e †ect of low doses of these surfactants on the sorption characteristics of the fungicide triticonazole was investigated. The critical micellar concentration (CMC) of the surfactants in pure water and soilÈwater systems, and surfactant sorption were estimated by surface tension measurements using a batch equilibration technique. Triticonazole sorption, alone and in the presence of low doses of surfactants, was also measured by batch equilibration. CMC of the alkylphenol surfactants increased with their HLB. The sorption of surfactants increased with their lipophilicity. CMC in the soilÈwater systems were considerably higher than in pure water. Sorption of the most lipophilic alkylphenol surfactants at the higher doses signiÐcantly increased triticonazole sorption. Proposed mechanisms are modiÐcations of soil surface properties, and increase of soil organic carbon content. Sorption of the other nonionic and anionic surfactants only resulted in monomeric surfactant concentrations in pore water, and did not a †ect triticonazole sorption.