Effects of a manganese oxide-modified biochar composite on adsorption of arsenic in red soil
Effects of a manganese oxide-modified biochar composite on adsorption of arsenic in red soil
复制标题
氧化锰改性生物炭复合材料对红壤吸附砷的影响
DOI：
10.1016/j.jenvman.2015.08.020
复制
发表时间：
2015-11-01
影响因子：
8.7
通讯作者：
Qiu, Weiwen
中科院分区：
文献类型：
--
作者：
Yu, Zhihong;Zhou, Li;Qiu, Weiwen
以高锰酸钾和生物质炭为原料，通过热解制备了氧化锰改性生物质炭复合材料（MBC），研究了其对红壤中砷的吸附性能。吸附实验，使用批处理程序被用来估计砷吸附容量的吸收剂材料。利用吸附和脱附等温线、傅里叶变换红外光谱（FTIR）和X射线光电子能谱（XPS）对所制备的吸附材料进行表征，并提出了MBC除砷的可能机理。红土MBC混合物中的砷表现出比用原始生物炭改良的土壤中更低的迁移率。尽管氧化锰的浸渍降低了生物炭的比表面积，但土壤MBC混合物的去除性能的改善归因于较低的H/C比、较高的O/C比、较高的表面亲水性和较高的表面吸附能力。砷的保留增加，生物炭含量的增加，主要是由于土壤pH值的增加。几个含氧官能团，特别是O-H，C=O，Mn-O，和Si-O，参与吸附过程中，锰氧化物在砷的氧化中发挥了重要作用。这项研究突出了MBC作为吸附剂固定砷用于红壤地区污染土地修复的潜力。(C)2015爱思唯尔有限公司版权所有。
The arsenic adsorption capacity of a manganese oxide-modified biochar composite (MBC), prepared by pyrolysis of a mixture of potassium permanganate and biochar, was investigated in red soil. Adsorption experiments using batch procedures were used to estimate the arsenic adsorption capacities of the absorbent materials. Adsorption and desorption isotherms, Fourier-transform infrared spectroscopy (FTIR), and X-ray photoelectron spectroscopy (XPS) were used to characterise the prepared adsorbent materials, and a plausible mechanism for arsenic removal by MBC was proposed. Arsenic in red soil MBC mixtures exhibited lower mobility than that in soils amended with pristine biochar. The improved removal performance of soil MBC mixtures was attributed to a lower H/C ratio, higher O/C ratio, higher surface hydrophilicity, and higher surface sorption capacity, even though the impregnation of manganese oxide decreased the specific surface area of the biochar. Arsenic retention increased as the biochar content increased, mainly owing to an increase in soil pH. Several oxygenated functional groups, especially O-H, C=O, Mn-O, and Si-O, participated in the adsorption process, and manganese oxides played a significant role in the oxidation of arsenic. This study highlights the potential of MBC as an absorbent to immobilise arsenic for use in contaminated land remediation in the red soils region. (C) 2015 Elsevier Ltd. All rights reserved.