Departament d'Enginyeria Química, Universitat Politècnica de Catalunya, Av Diagonal 647, 08028 Barcelona, Spain.
J Colloid Interface Sci. 2010 Aug 1;348(1):293-7. doi: 10.1016/j.jcis.2010.04.046. Epub 2010 Apr 24.
Natural hematite was used for the removal of arsenic(III) and arsenic(V) from aqueous solution. The experimental breakthrough curves were obtained in fixed-bed columns. The transport of arsenic in a simplified fixed-bed configuration was quantified by using the CXTFIT code, which was used to estimate the transport and sorption parameters of the convective-dispersive equation (CDE) and the two-site deterministic nonequilibrium (TSM/CDE) model by fitting the models to the experimental breakthrough curves (BTC). The prediction of the breakthrough curves performed by the two-site nonequilibrium sorption model resulted in a good fit, indicating that this model can properly describe the transport and sorption processes of arsenic on natural hematite. Additionally the parameters obtained indicate that nonequilibrium sorption governs the As(III) and As(V) uptake onto hematite in a fixed-bed column. No significant differences in the transport and sorption parameters of As(III) and As(V) on natural hematite were obtained; the retardation factor values were in the same order of magnitude for both species.
天然赤铁矿被用于从水溶液中去除砷(III)和砷(V)。在固定床柱中获得了实验突破曲线。使用 CXTFIT 代码量化了简化固定床配置中砷的传输，该代码用于通过拟合模型到实验突破曲线 (BTC) 来估计对流弥散方程 (CDE) 和双位点确定性非平衡 (TSM/CDE) 模型的传输和吸附参数。双位点非平衡吸附模型对突破曲线的预测得到了很好的拟合，表明该模型可以正确描述砷在天然赤铁矿上的传输和吸附过程。此外，获得的参数表明，非平衡吸附控制着固定床柱中砷(III)和砷(V)在赤铁矿上的吸收。在天然赤铁矿上，砷(III)和砷(V)的传输和吸附参数没有明显差异；两种物质的阻滞因子值处于同一数量级。
