期刊
JOURNAL OF HAZARDOUS MATERIALS
卷 262, 期 -, 页码 1196-1203出版社
ELSEVIER
DOI: 10.1016/j.jhazmat.2012.06.051
关键词
Trace element; Adsorption; Desorption; Mining waste
资金
- Minas Gerais State Research Agency (FAPEMIG)
- Federal Agency of Support and Evaluation of Postgraduate Education (CAPES)
- National Council for Scientific and Technological Development (CNPq)
Mining by-products have been tested as adsorbents for arsenic in order to reduce As bioavailability. This study evaluated a red mud (RM) treated with or without phosphogypsum (G) in order to improve its As retention. Red mud and G samples and their mixtures were chemically and mineralogically characterized to gather information concerning their composition, which is key for a better understanding of the adsorbent properties. Phosphogypsum was added to RM in the following proportions: 0, 1, 2, 5, 10, and 25% by weight. These mixtures were subjected to As adsorption and desorption and tested for their maximum adsorption capacity of As (As-MAC). Arsenic adsorption increased upon increasing the proportion of Gadded to RM. The As-MAC at pure RM reached 909 mg kg(-1), whereas the 75%-RM + 25%-G mixture sorbed up to 3333 mg kg(-1) of As, i.e., a 3.5-fold increase in As-MAC. Using G in mixtures with RM increases the efficiency of As adsorption due to the presence of Ca2+, which alters the charge balance of the adsorbent, leading to the formation of ternary complexes. Addition of G to RM is thus a promising technique to improve As retention, while providing additional value to both by-products, G and RM. (C) 2012 Elsevier B.V. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据