人工合成铁铝矿对As(V)吸附的研究.PDFVIP

中国环境科学 2011,31(4) ：603~610 China Environmental Science 人工合成铁、铝矿对 As(V) 吸附的研究 吴萍萍 1,2, 曾希柏 1* (1. 中国农业科学院农业环境与可持续发展研究所/农业部农业环境与气候变化重点开放实验 ,北京 100081 ；2.安徽农业科学院土壤肥料研究所,安徽 合肥 230031) 摘要：采用批实验方法研究了人工合成铁、铝矿物对 As(V) 的吸附,考察吸附时间及溶液 pH 值对 As(V)吸附的影响.结果表明,不同类型铁、铝 矿对 As(V) 的吸附量均表现出随初始 As(V)浓度(0.1~100mg/L)的增加而增加的趋势,其中水铁矿的吸附量在整个浓度范围内始终呈上升趋势, 初始浓度为 100mg/L As(V)时的吸附量为22.56mg/g,而针铁矿、水铝矿和赤铁矿的吸附量在低初始浓度时上升较快,随浓度升高上升幅度减缓 直至平衡,其中赤铁矿的吸附量最小,100mg/L As(V)时的吸附量为4.75mg/g.Freundlich 方程对吸附数据的拟合效果优于 Langmuir 方程,吸附能 力表现为水铁矿最高,水铝矿和针铁矿相近,赤铁矿较低.随着吸附时间的增加,4 种铁、铝矿物对 As(V) 的吸附量都逐渐增加,尤其是水铁 矿,10min 内即达到平衡吸附量的96.3%;水铝矿和针铁矿在 48h 时吸附量分别为平衡吸附量的 97.2%和 97.4%;赤铁矿则需 96h 才基本达到平 衡.除水铁矿外,4 种动力学方程对其他矿物动力学曲线的拟合均较好,尤其是双常数方程.pH 值对矿物吸附As(V) 的影响受As(V)初始浓度的影 响,初始浓度较低时,铁、铝矿的吸附量仅在极碱条件下(pH10)降低,而初始浓度较高时则表现为随pH 值升高直线下降的趋势. 关键词：砷；水铁矿；针铁矿；赤铁矿；水铝矿；吸附；pH 中图分类号：X132 文献标识码：A 文章编号：1000-6923(2011)04-0603-08 Study on arsenate adsorption by synthetic iron and aluminum oxides/hydroxides. WU Ping-ping1, 2, ZENG Xi-bai1* (1.Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences/Key Laboratory of Agro-Environment and Climate Change, Ministry of Agriculture, Beijing 100081, China ；2.Institute of Research for Soil and Fertilizer, Anhui Academy of Agricultural Sciences, Hefei 230031, China). China Environmental Science, 2011,31(4)：603~610 Abstract ：Batch experiments were used to investigate arsenate adsorption by synthetic iron and aluminum oxides/hydroxides. The effects of adsorption time and pH on the adsorption behavior were also studied. The results showed that, As(V) adsorption by four iron and aluminum oxides/hydroxides increased with initial As(V) concentrations (0.1~100 mg/L), in which ferrihydrite showed a rising adsorption trend in the