Department of Sustainable Development, Environmental Science and Engineering, Kungliga Tekniska Högskolan, Brinellvägen 28, SE-100 44 Stockholm, Sweden E-mail:
Water and Sanitation Department, African Development Bank, Tunis, Tunisia.
Water Sci Technol. 2014;69(11):2230-6. doi: 10.2166/wst.2014.147.
Untreated and chemically treated Albizia coriaria, Erythrina abyssinica and Musa spp. were studied in batch for uptake of Cd(2+) and Pb(2+) ions at pH 2.0-9.0 and agitation time of 30-390 min. Optimum biosorption conditions were pH 4 for Pb(2+) ions and pH 5 for Cd(2+) ions, contact time was 3.5 hours at 24 ± 1 °C for 10 mg/L biosorbent dosage and initial metal ions concentration of 20 mg/L. Chemical treatment had a 10-17% biosorption efficiency enhancement for Cd(2+) ions and a 1.6-2.3% reduction effect for Pb(2+) ions. The sorption capacities for Cd(2+) and Pb(2+) ions for treated biosorbents were 1.760-1.738 mg g(-1) compared to 1.415-1.539 mg g(-1) for untreated materials. The pseudo second-order model suitably fitted the Cd(2+) and Pb(2+) ions biosorption data with regression coefficients (R(2)) of 0.9784-0.9999. Fitting of the Ho model to the experimental data showed that the biosorption mechanism for both metal ions studied was mainly a chemisorption process. Therefore, treated A. coriaria, E. abyssinica and Musa spp. were potential biosorbents for remediation of Cd(2+) ions and the untreated materials suitable for removing Pb(2+) ions from contaminated aqueous media.
未经处理和化学处理的 Albizia coriaria、Erythrina abyssinica 和 Musa spp. 在 pH 2.0-9.0 和搅拌时间 30-390 分钟的批处理条件下研究了对 Cd(2+)和 Pb(2+)离子的吸附。最佳吸附条件为 pH 4 对 Pb(2+)离子和 pH 5 对 Cd(2+)离子，接触时间为 24 ± 1 °C 时 3.5 小时，10 mg/L 生物吸附剂剂量和 20 mg/L 初始金属离子浓度。化学处理对 Cd(2+)离子的生物吸附效率提高了 10-17%，对 Pb(2+)离子的降低效果为 1.6-2.3%。处理后的生物吸附剂对 Cd(2+)和 Pb(2+)离子的吸附容量分别为 1.760-1.738 mg/g，而未处理材料的吸附容量分别为 1.415-1.539 mg/g。准二级模型适合拟合 Cd(2+)和 Pb(2+)离子的生物吸附数据，回归系数（R(2)）为 0.9784-0.9999。Ho 模型对实验数据的拟合表明，研究的两种金属离子的吸附机制主要是化学吸附过程。因此，经处理的 A. coriaria、E. abyssinica 和 Musa spp. 是修复 Cd(2+)离子的潜在生物吸附剂，未经处理的材料适合从受污染的水介质中去除 Pb(2+)离子。
