Center for Environment and Water Resources, College of Chemistry and Chemical Engineering, Central South University, Changsha 410083, China E-mail:
Water Sci Technol. 2019 Aug;80(4):644-653. doi: 10.2166/wst.2019.284.
Adsorption was found to be an acceptable treatment option to remove geosmin (GSM) and 2-methylisoborneol (2-MIB). It is meaningful to investigate the adsorption capacity of granular activated carbon (GAC) for the two algal odorants in water, and the influences of natural organic material (NOM) and particle size. The adsorption process was studied with the four isotherm models (Langmuir, Freundlich, Temkin, and modified Freundlich), four kinetic models (pseudo first-order, pseudo second-order, Elovich, and intra-particle), and thermodynamics. The results showed that the adsorption of both compounds could be best described by the modified Freundlich isotherm and pseudo second-order model, and the obtained thermodynamic parameters (changes in heat of adsorption, entropy, and Gibbs free energy) revealed that the adsorption was endothermic and spontaneous. Downsizing the particle size of GAC was effective for improving the adsorption capacity and rate. The concentrations of the two odorants could be reduced from 500 ng L to less than 10 ng L with the presence of NOM (<20 mg L total organic carbon, TOC).
吸附被发现是一种可接受的处理方法，可用于去除土臭素 (GSM) 和 2-甲基异莰醇 (2-MIB)。研究颗粒状活性炭 (GAC) 对水中这两种藻类气味物质的吸附能力以及天然有机物 (NOM) 和粒径的影响具有重要意义。通过四种等温线模型（朗缪尔、弗伦德利希、坦金和修正弗伦德利希）、四种动力学模型（拟一级、拟二级、艾洛维和内颗粒）以及热力学对吸附过程进行了研究。结果表明，两种化合物的吸附均可用修正的弗伦德利希等温线和拟二级模型来最好地描述，并且获得的热力学参数（吸附热、熵和吉布斯自由能的变化）表明吸附是吸热和自发的。减小 GAC 的粒径对于提高吸附能力和速率是有效的。在存在 NOM（<20 mg L 总有机碳，TOC）的情况下，两种气味物质的浓度可以从 500 ng L 降低到 10 ng L 以下。
