Department of Chemistry, College of Science, Shahid Chamran University, P,O, Box: 6135743337, Ahvaz, Iran.
J Environ Health Sci Eng. 2014 Mar 12;12(1):62. doi: 10.1186/2052-336X-12-62.
Efficiency and performance of Almond shell (AS) adsorbent for the removal and recovery of Acid Blue 129 (AB129) from wastewater is presented in this report. The influence of variables including pH, initial dye concentration, adsorbent dosage, particle size, contact time and temperature on the dye removal have been investigated in batch method by one at a time optimization method. The experimental equilibrium data were tested by four widely used isotherm models namely, Langmuir, Freundlich, Tempkin and Dubinin-Radushkevich (D-R). It was found that adsorption of AB129 on AS well with the Langmuir isotherm model, implying monolayer coverage of dye molecules onto the surface of the adsorbent. More than 98% removal efficiency was obtained within 14 min at adsorbent dose of 0.4 g for initial dye concentration of 40 mg/L at pH 2. Kinetics of the adsorption process was tested by pseudo-first-order and pseudo-second-order kinetics, and intraparticle diffusion mechanism. Pseudo-second-order kinetic model provided a better correlation for the experimental data studied in comparison to the pseudo-first-order model. Calculation of various thermodynamic parameters such as, Gibb's free energy, entropy and enthalpy of the on-going adsorption process indicate feasibility and endothermic nature of AB129 adsorption on all adsorbents. This work can be used in design of adsorption columns for dyes removal.
本报告介绍了杏仁壳（AS）吸附剂用于从废水中去除和回收酸性蓝 129（AB129）的效率和性能。通过单因素优化法，在批处理法中研究了变量（包括 pH 值、初始染料浓度、吸附剂用量、粒径、接触时间和温度）对染料去除的影响。通过四种广泛使用的等温线模型（朗缪尔、弗伦德利希、Tempkin 和 Dubinin-Radushkevich（D-R））对实验平衡数据进行了测试。结果表明，AB129 在 AS 上的吸附符合朗缪尔等温线模型，这意味着染料分子单层覆盖在吸附剂表面。在 pH 值为 2、初始染料浓度为 40mg/L、吸附剂用量为 0.4g 的条件下，14min 内的去除效率超过 98%。通过拟一级和拟二级动力学以及内扩散机制对吸附过程的动力学进行了测试。与拟一级动力学模型相比，拟二级动力学模型为实验数据提供了更好的相关性。对正在进行的吸附过程的各种热力学参数（如吉布斯自由能、熵和焓）的计算表明，AB129 在所有吸附剂上的吸附是可行的，并且是吸热的。这项工作可用于设计用于去除染料的吸附柱。
