Sorption and Preconcentration of the Herbicides Atrazine, Simazine, and Ametryne on Montmorillonite

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)This paper describes the treatment of montmorillonite (MT), with K+ (MTK), Na+ (MTNa), and Ca2+ (MTCa) to explore the use of these minerals for the extraction and preconcentration of the herbicides atrazine, simazine, and ametryne from aqueous medium. In the sorption process, the three materials exhibited good performance; ametryne was totally sorbed. For atrazine and simazine, MTK showed a removal between 90% (atrazine) and higher than 99% (simazine). The recoveries employing solutions at initial concentrations of 100 mu gL1 of each herbicide showed results of 90% (simazine) and 94% (atrazine), whereas for 10 mu gL1, the results of 73% (simazine) and 81% (atrazine) were obtained. On the other hand, ametryne showed poor recovery values (25 to 40%), probably due to a stronger interaction with MTK, lowering the recovery values. Based on the results for atrazine and simazine, MTK presented good features to be used as sorbent phase and for preconcentration, being easily prepared with low cost, demanding low amounts to be used for this purpose, providing fast sorption of atrazine and simazine, and with appropriate recoveries.463439451Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)CAPES [PROCAD 0082/05-8