Quantifying Arsenic Leaching from Soils Using a Fractional-Derivative Model

Abstract:

Arsenic leaching from soils can exhibit multiple-rate kinetics due to the heterogeneity nature of the medium, motivating the development of a fractional-order derivative model (FDM). The sorption-desorption process in saturated natural soils may not be limited to be a single rate or can reach equilibrium quickly, even at the laboratory scale. Applications of the FDM show that the multi-rate mass transfer quantifies the multi-stage desorption in Arsenic leaching characterized by the heavy late-time tailing behavior.