The present study evaluates the feasibility of using natural Lagerstroemia speciosa bark (NLSB) and chemically modified Lagerstroemia speciosa bark (CLSB) in removing Cr(VI) from aqueous solution in fixed bed column process. The effect of influent flow rate, bed depth and inlet Cr(VI) ion concentration on the Cr(VI) removal capacity of NLSB and CLSB was investigated. The column exhaustion time increased with increase in bed depth and reverse trend was obtained with increase in flow rate and influent Cr(VI) ion concentration. The Bohart–Adams, Thomas and Yoon–Nelson dynamic models were applied at various studied experimental conditions to predict the breakthrough curve behavior and to determine the characteristics fixed bed column parameters that are very crucial in scale up of the column process for its industrial scale application. Both Thomas and Yoon–Nelson models showed very good agreement with the column data and explained the mechanism of Cr(VI) adsorption by NLSB and CLSB in column process. The high Cr(VI) adsorption capacity and regeneration efficiency of NLSB and CLSB in column suggest its applicability in removal of Cr(VI) present in industrial effluents.

本研究评估使用天然紫薇树皮（NLSB）和化学修饰的紫薇树皮的可行性树皮（CLSB）在固定床柱工艺中从水溶液中去除Cr（VI）的过程。研究了进水流速，床层深度和入口Cr（VI）离子浓度对NLSB和CLSB去除Cr（VI）的影响。随着柱床深度的增加，柱的排气时间增加，而随着流速和进水Cr（VI）离子浓度的增加，则获得了相反的趋势。Bohart-Adams，Thomas和Yoon-Nelson动力学模型在各种研究条件下得到应用，以预测突破曲线的行为并确定特性床固定床参数，这对于扩大其工业规模的色谱柱工艺至关重要。Thomas模型和Yoon-Nelson模型均与色谱柱数据显示出很好的一致性，并解释了NLSB和CLSB在色谱柱过程中吸附Cr（VI）的机理。色谱柱中NLSB和CLSB的高Cr（VI）吸附能力和再生效率表明，它适用于去除工业废水中存在的Cr（VI）。