Gupta Vinod K, Sharma Saurabh
Department of Chemistry, Indian Institute of Technology Roorkee, (Uttranchal).
Environ Sci Technol. 2002 Aug 15;36(16):3612-7. doi: 10.1021/es020010v.
Red mud, an aluminum industry waste, has been converted into an inexpensive and efficient adsorbent. The product obtained has been characterized and utilized in batch and column operations for the removal of cadmium and zinc from aqueous solutions over a wide range of initial metal ion concentrations (1.78 x 10(-5) to 1.78 x 10(-3) M for Cd2+ and 3.06 x 10(-5) to 3.06 x 10(-3) M for Zn2+; contact time, 24 h) adsorbent dose (5-20 g/L), and pH (1.0-6.0). The removal of Cd2+ and Zn2+ was almost complete at low concentrations, while it was 60-65% at higher concentrations at optimum pH's of 4.0 and 5.0, respectively, with 10 g/L of adsorbent in an 8-10 h equilibration time. The adsorption decreased with increase in temperature. Kinetic studies have been used to describe the mechanism of adsorption. Chemical regeneration of the columns has been achieved with 1% HNO3.
赤泥，一种铝工业废料，已被转化为一种廉价且高效的吸附剂。所获得的产品已进行表征，并用于间歇和柱操作中，以在较宽的初始金属离子浓度范围内（Cd2+为1.78×10(-5)至1.78×10(-3) M，Zn2+为3.06×10(-5)至3.06×10(-3) M；接触时间为24小时）、吸附剂剂量（5 - 20 g/L）和pH值（1.0 - 6.0）下去除水溶液中的镉和锌。在低浓度下，Cd2+和Zn2+的去除几乎是完全的，而在较高浓度下，分别在最佳pH值4.0和5.0时，去除率为60 - 65%，吸附剂用量为10 g/L，平衡时间为8 - 10小时。吸附率随温度升高而降低。动力学研究已用于描述吸附机理。已用1% HNO3实现了柱的化学再生。
