The use of raw and acid-pretreated bivalve mollusk shells to remove metals from aqueous solutions
The use of raw and acid-pretreated bivalve mollusk shells to remove metals from aqueous solutions
复制标题
DOI：
10.1016/j.jhazmat.2009.02.009
复制
发表时间：
2009-08-30
影响因子：
13.6
通讯作者：
Li, Youzhi
中科院分区：
文献类型：
--
作者：
Liu, Yang;Sun, Changbin;Li, Youzhi
从工业废水中去除重金属不仅是为了保护环境中的生物体，而且还通过使其重新使用来保护资源，如金属和水。为克服常规物化处理技术成本高、易造成二次污染的缺点，需要环境友好、价格低廉的吸附剂。在这项研究中，使用的原料和酸预处理的双壳类软体动物壳（BMS），以消除从水溶液中的金属与单一或混合的金属进行了评估，在不同的BMS剂量，pH值和温度在批振荡实验在实验室条件下。用该BMSs处理CuSO 4中心点5 H（2）O溶液时，未处理和酸处理的BMSs对Cu的吸附容量分别为38.93 mg/g和138.95 mg/g。随着初始pH值的增加，BMSs对铜的去除率（CRE）大大提高，在初始pH值为5时，CRE可达99.51%。相反，酸预处理的BMS的CRE在1-5的pH范围内保持在99.48-99.52%。此外，当温度从15 ℃变化到40 ℃时，原始和酸预处理的BMS的CRE值没有很大变化。此外，在12个吸附-解吸循环中保持原始BMS的CRE值，在最后一个循环中观察到98.4%的CRE。最后，将其应用于电镀废水的处理。未经处理的BMSs对Fe、Zn和Cu的去除率分别为99.97%、98.99%和87%，而经酸处理的BMSs对Fe、Zn和Cu的去除率分别为99.98%、99.43%和92.13%。离子交换实验表明，BMSs从水溶液中吸附金属的机制之一与离子交换有关，特别是处理液中的金属离子与BMSs中的Ca 2+之间的离子交换。红外吸收光谱分析表明，酸预处理后的BMSs表面出现了-OH、-NH、C=O和S=O等负电荷基团。扫描电子显微镜显示，酸预处理使所用的BMS形成片状结构，具有光滑的表面，可以提供更好的界面结合金属离子。(C)2009年由Elsevier B. V.出版
Heavy metal removal from industrial wastewater is not only to protect living organisms in the environment but also to conserve resources such as metals and water by enabling their reuse. To overcome the disadvantage of high cost and secondary pollution by the conventional physico-chemical treatment techniques, environmentally benign and low-cost adsorbents are in demand. In this study, the use of raw and acid-pretreated bivalve mollusk shells (BMSs) to remove metals from aqueous solutions with single or mixed metal was evaluated at different BMSs doses, pH and temperatures in batch shaking experiments in laboratory conditions. When the BMSs were used to treat CuSO4 center dot 5H(2)O solution, the copper sorption capacities of the raw and acid-pretreated BMSs were approximately 38.93 mg/g and 138.95 mg/g, respectively. The copper removal efficiency (CRE) of the raw BMSs became greatly enhanced with increasing initial pH. reaching 99.51% at the initial PH 5. Conversely, the CRE of the acid-pretreated BMSs was maintained at 99.48-99.52% throughout the pH range of 1-5. Furthermore, the CRE values of the raw and acid-pretreated BMSs were not greatly changed when the temperature was varied from 15 degrees C to 40 degrees C. In addition, the CRE value of the raw BMSs was maintained for 12 cycles of sorption-desorption with a CRE of 98.4% being observed in the final cycle. Finally, when the BMSs were used to treat electroplating wastewater. the removal efficiencies (REs) of the raw BMSs were 99.97%, 98.99% and 87% for Fe, Zn and Cu, respectively, whereas the REs of the acid-pretreated BMSs were 99.98%, 99.43% and 92.13%, respectively. Ion exchange experiments revealed that one of mechanisms for metal sorption by the BMSs from aqueous solution is related to ion exchange, especially between the metal ions in the treated solution and Ca2+ from BMSs. Infrared absorbance spectra analysis indicated that the acid pretreatment led to occurrence of the groups (i.e. -OH, -NH, C=O and S=O) of negative charge in treated BMSs. Scanning electron microscopy revealed that acid pretreatment enabled the used BMSs to form the flake-shaped structure with smooth surfaces that can supply a better interface for binding metal ions. (C) 2009 Published by Elsevier B.V.