Department of Mining & Metallurgical Eng., Amirkabir University of Technology, Tehran, Iran.
Department of Mining & Metallurgical Eng., Amirkabir University of Technology, Tehran, Iran.
J Environ Manage. 2018 Jan 15;206:266-275. doi: 10.1016/j.jenvman.2017.10.037. Epub 2017 Oct 27.
In this study, waste solids of the alumina industry (red mud) have been modified and utilized as a ferricyanide adsorbent which is characterized by XRD, XRF, FTIR, SEM, EDX, ICP and BET analysis. The four modification methods including the processes of washing with seawater (B), acid treatment Bauxsol (ATB), activated ATB using ammonia (ABA), and activated Bauxsol using cetyltrimethylammonium bromide (CTAB) (ABC) were evaluated to increase the reactivity of red mud (RM) for ferricyanide removal. The ferricyanide adsorption capacity was obtained at 12.40, 6.84, 2.95, 2.50 and 0.44 (mg/g) for ABC, ATB, ABA, B and RM, respectively. The CTAB with a concentration above the critical micelle concentration changed the negative charge of red mud to positive charge. It decreased the negative charge repulsion force between the Bauxsol surface and ferricyanide ions. The adsorption capacity of ferricyanide was decreased from 12.40 to 2.75 (mg/g) with increasing the adsorbent amount from 0.5 to 5 (g). The results showed that the activated Bauxsol using CTAB could be effectively used as a new adsorbent for ferricyanide ions from wastewaters.
在这项研究中，氧化铝工业的废固（赤泥）经过改性后被用作铁氰化物吸附剂，其特性通过 XRD、XRF、FTIR、SEM、EDX、ICP 和 BET 分析进行了表征。本研究评估了四种改性方法，包括用海水洗涤（B）、用 Bauxsol 酸处理（ATB）、用氨激活 ATB（ABA）和用十六烷基三甲基溴化铵（CTAB）激活 Bauxsol（ABC），以提高赤泥（RM）对铁氰化物的去除率。铁氰化物的吸附容量分别为 ABC、ATB、ABA、B 和 RM 的 12.40、6.84、2.95、2.50 和 0.44（mg/g）。CTAB 浓度超过临界胶束浓度时，会将赤泥的负电荷变为正电荷。它降低了 Bauxsol 表面和铁氰化物离子之间的负电荷斥力。随着吸附剂用量从 0.5 增加到 5（g），铁氰化物的吸附容量从 12.40 下降到 2.75（mg/g）。结果表明，用 CTAB 激活的 Bauxsol 可以有效地用作废水中铁氰化物离子的新型吸附剂。
