Gupta V K, Gupta M, Sharma S
Department of Chemistry, University of Roorkee, Roorkee-247 667 UP, India.
Water Res. 2001 Apr;35(5):1125-34. doi: 10.1016/s0043-1354(00)00389-4.
Red mud, an aluminium industry waste, has been converted into an inexpensive and efficient adsorbent and used for the removal of lead and chromium from aqueous solutions. Effect of various factors on the removal of these metal ions from water (e.g. pH, adsorbent dose, adsorbate concentration, temperature, particle size, etc.) has been studied and discussed. The effect of presence of other metal ions/surfactants on the removal of Pb2+ and Cr6+ has also been studied. The material exhibits good adsorption capacity and the data follow both Freundlich and Langmuir models. Thermodynamic parameters indicate the feasibility of the process. Kinetic studies have been performed to understand the mechanism of adsorption. Dynamic modelling of lead and chromium removal on red mud has been undertaken and found to follow first-order kinetics. The rate constant and mass transfer coefficient have also been evaluated under optimum conditions of removal in order to understand the mechanism. Column studies have been carried out to compare these with batch capacities. The recovery of Pb2+ and Cr6+ and chemical regeneration of the spent column have also been tried.
赤泥是一种铝工业废料，已被转化为一种廉价且高效的吸附剂，并用于去除水溶液中的铅和铬。研究并讨论了各种因素（如pH值、吸附剂用量、吸附质浓度、温度、粒径等）对从水中去除这些金属离子的影响。还研究了其他金属离子/表面活性剂的存在对去除Pb2+和Cr6+的影响。该材料具有良好的吸附能力，数据符合Freundlich和Langmuir模型。热力学参数表明该过程的可行性。进行了动力学研究以了解吸附机理。对赤泥去除铅和铬进行了动态建模，发现其遵循一级动力学。还在最佳去除条件下评估了速率常数和传质系数，以了解其机理。进行了柱实验以将其与间歇容量进行比较。还尝试了回收Pb2+和Cr6+以及对用过的柱进行化学再生。
