Evaluating the Adsorptive Capacity of Aluminoferric Red Oxisol in Reducing the Availability of 2,4-Dichlorofenoxiacetic Acid
D.P. Baldissarelli, D.P. Siqueira, A. Dervanoski, M. Morais, L. Galon, E.P. Korf, G.D.L.P. Vargas
Soils and Rocks, São Paulo, 42(3): 301-309, September-December, 2019 | PDF
Increased food production results in the development and application of agrochemicals to control weeds, which can affect agricultural production. Pesticides contaminate the environment and change soil and water quality. Therefore, to improve the understanding of the adsorption mechanism of 2,4-dichlorophenoxyacetic acid (2,4-D) in aluminoferric red oxisol we have conducted an adsorption study using Langmuir and Freundlich isotherms, treating kinetic data using pseudo first-order, pseudo second-order, and intraparticle diffusion models. The results showed the Freundlich isotherm fits the experimental data best, revealing favorable adsorption and a strong attraction between adsorbent molecules, considering the nF and kF model parameters of 3.7 and 34.21 L/g, respectively. The kinetic model with the best fit was the pseudo second-order model. The intraparticle diffusion model indicated the second step as the process controlling step, revealing kD of 12.36 and 4.42 mg/g for the concentrations of 6352.80 mg/L and 1087.20 mg/L, respectively. Higher kD represents lower transport resistance and higher motive power for mass transfer.
Submitted on March 18, 2019; Final Acceptance on August 2, 2019; Discussion open until April 30, 2020.