Adsorption isotherm modeling of carbendazim and flumetsulam onto homoionic-montmorillonite clays: comparison of linear and nonlinear models

Authors : Yassine El MAATAOUİ, Mohamadine El M`RABET, Abdelkrim MAAROUFI, Hassan OUDDA, Abdelmalek DAHCHOUR

Pages : 514-524

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Publication Date : 0000-00-00

Article Type : Research Paper

Abstract :This study deals with the adsorption of two pesticides, carbendazim and flumetsulam, from aqueous solutions onto four homoionic-montmorillonite clays insert ignore into journalissuearticles values(Ag$^{+}$, Zn$^{2+}$, Cu$^{2+}$, and H$^{+});$. Equilibrium adsorption isotherm data were analyzed using Freundlich, Dubinin-Radushkevich, and Temkin isotherms. Linear and nonlinear fitting methods were compared to determine the best-fitting isotherms for the experimental data. Three error analysis methods were used to evaluate the data for each method: the coefficient of determination insert ignore into journalissuearticles values(R$^{2});$, sum of squared errors insert ignore into journalissuearticles values(SSE);, and chi-square test insert ignore into journalissuearticles values($\chi^{2});$. Equilibrium adsorption isotherms exhibited that the carbendazim adsorption mainly involved cation exchange with homoionic-montmorillonite adsorbents. However, for flumetsulam, the main mechanisms were possibly the cation bridging by Ag$^{+}$, Zn$^{2+}$, and Cu$^{2+}$ cations and the surface complexation reactions of the adsorption on homoionic-montmorillonite insert ignore into journalissuearticles values(H$^{+});$ adsorbent. The modeling results showed that the nonlinear Freundlich model could fit the data better than the Dubinin-Radushkevich or Temkin models, with relatively higher R$^{2}$ and smaller SSE and $\chi ^{2}$ values. Thus, the nonlinear method is a better way to obtain the isotherm parameters.
Keywords : Adsorption, homoionic montmorillonite, carbendazim, flumetsulam, modeling analysis