School of Physics and Electronic Engineering, Fuyang Normal University, Fuyang 236037, China.
School of Resources and Environment, Anhui Agricultural University, Hefei 230036, China.
Int J Environ Res Public Health. 2018 Jun 24;15(7):1321. doi: 10.3390/ijerph15071321.
Tea waste (biosorbent) was characterized by BET, SEM, FTIR, XPS, solid state C-NMR and applied to remove methylene blue (MB) from aqueous solution. The effect of different factors on MB removal, kinetics, isotherms and potential mechanism was investigated. The results showed that tea waste contains multiple organic functional groups. The optimum solid-to-liquid ratio for MB adsorption was 4.0 g·L and the initial pH of the MB solution did not need to be adjusted to a certain value. The pseudo-second-order model could well fit the adsorption kinetic process. The adsorption process could be divided into two stages: a fast adsorption stage and a slow adsorption stage. The adsorption isotherm could be well described by Langmuir and Temkin isotherm models. The maximum adsorption amount could reach 113.1461 mg·g based on Langmuir isotherm fitting. Desorption and reusability experiments showed that MB adsorption onto tea waste could be stable and could not cause secondary pollution. The interaction mechanism between tea waste and MB involved electrostatic attraction, hydrogen bond, ion exchange, π-π binding. The organic functional groups of tea waste played an important role during the MB removal process. Therefore, tea waste has the potential to act as an adsorbent to remove MB from aqueous solution.
茶叶废料（吸附剂）采用 BET、SEM、FTIR、XPS、固态 C-NMR 进行了表征，并应用于从水溶液中去除亚甲基蓝（MB）。研究了不同因素对 MB 去除效果、动力学、等温线和潜在机制的影响。结果表明，茶叶废料含有多种有机官能团。MB 吸附的最佳固液比为 4.0 g·L，且 MB 溶液的初始 pH 值无需调节到一定值。准二级动力学模型能够很好地拟合吸附动力学过程。吸附过程可以分为两个阶段：快速吸附阶段和缓慢吸附阶段。吸附等温线可以很好地用朗缪尔和坦金等温线模型来描述。根据朗缪尔等温线拟合，最大吸附量可达 113.1461 mg·g。解吸和重复使用实验表明，MB 吸附在茶叶废料上可以稳定，不会造成二次污染。茶叶废料与 MB 之间的相互作用机制涉及静电吸引、氢键、离子交换、π-π 键合。茶叶废料中的有机官能团在 MB 去除过程中起着重要作用。因此，茶叶废料有潜力作为吸附剂从水溶液中去除 MB。
