Adsorption of Rhodamine B onto a Yellow Brown Soil: Kinetics, Thermodynamics, and Role of Soil Organic Matter

摘要

The eniironmental behavior of organic pollutants in soils depends on their adsorption properties onto soils. in this article, the adsorption process of Rhodarnine B (RhB) from an aqueous solution onto a yellow brown soil in Central China was studied. The isotherms and the kinetic data of the R19B adsorption onto the soil were well approached by the Freundlich isotherm model (R-2;: 0.999) and the pseudo-secondorder kinetic model (R-2> 0.99). The adsorption process of RbB onto the soil was endothermic and increased temperature was conducive to the adsorption p-ocess. The adsorption percentage of RhIl onto the soil decreased with increasing IV in e range from 2.32 to 10.96. With an increase in the ratio of soil to water the desorption rate of RhB in the soil clearly decreased. Soil organic matter is the main contribution to RbB adsorption onto the soil. A possible complav mechanism of the adsorption was suggested on the basis of concurrent operation of electrostatic attraction, and hydrogen and chemical bonding forces. (C) 2015 American Institute of Chemical Engineers En, iron Frog, 34: 1396-140;, 2015