Simulation of magnesium chloride vertical transport in column experiments.

The transport characteristics of manganese was investigated by soil columns experiments and provide essential data for aquifer remediation and groundwater protection in Yinchuan City. Soil column experiments involved a solution of manganese chloride in which the chloride ion was the chemical tracer. In the two column experiments, the breakthrough curve (BTC) for Cl– revealed the average linear flow velocity (2.937 and 3.921 cm/h) and longitudinal dispersivity (8.52 and 40.09 cm) of the sediment. The BTC of Mn2+ showed a significant delay compared to Cl–. The adsorptive equilibrium isotherm experiments showed that Ca2+ was the main desorption cation in the cation exchange process. The nonlinear retardation factor Rf (RfTM-1 = 13.97, RfTS-1 = 12.89) of Mn2+ is derived from thermodynamic principles. [ABSTRACT FROM AUTHOR]