College of Natural Resources and Environment, Northwest A&F University, Yangling, Shaanxi 712100, PR China.
College of Natural Resources and Environment, Northwest A&F University, Yangling, Shaanxi 712100, PR China.
Int J Biol Macromol. 2021 Jun 30;181:778-785. doi: 10.1016/j.ijbiomac.2021.03.166. Epub 2021 Mar 30.
A batch experiment was carried out in order to remove Hg from the aqueous solution as well as the polluted water using modified chitosan (CS) with polyamine compounds (triethylenetetramine (TETA), tetraethylenepentamine (TEPA)), and melamine. The obtained polyamine-co-melamine crosslinked CS derivatives (MCS-4N and MCS-5N) were characterized and used as adsorbents. In comparison to the raw CS, the modification significantly promoted the adsorption of Hg ions. The results of the pseudo-second-order kinetic model revealed that pH-dependent derivatives adsorbents achieved the equilibrium state within 12 h. The Langmuir model was best fitted with the Hg adsorption isotherm and showed the highest adsorption capacities of 140.3 and 109.7 mg/g for MCS-4N and MCS-5N, respectively. A slight decrease in the adsorption efficiency of Hg was noticed with the increment of the ionic strength of the solution. However, the studied adsorbents were easily regenerated and presented adequate reusability. The Hg adsorption was regulated by the combined process of coordination reaction and electrostatic attraction as well. The as-prepared polyamine-co-melamine crosslinked CS derivatives were found potential adsorbents for the adsorptive capture of Hg ions from aqueous solutions and polluted waters.
为了从水溶液和受污染的水中去除汞，采用带有多胺化合物（三乙烯四胺（TETA）、四乙烯五胺（TEPA））和三聚氰胺的改性壳聚糖（CS）进行了批实验。所得的多胺-三聚氰胺交联 CS 衍生物（MCS-4N 和 MCS-5N）进行了表征，并用作吸附剂。与原始 CS 相比，修饰显著促进了 Hg 离子的吸附。准二级动力学模型的结果表明，pH 依赖性衍生物吸附剂在 12 h 内达到平衡状态。Hg 吸附等温线最适合 Langmuir 模型，MCS-4N 和 MCS-5N 的最大吸附容量分别为 140.3 和 109.7 mg/g。随着溶液离子强度的增加，Hg 的吸附效率略有下降。然而，所研究的吸附剂易于再生，具有足够的可重复使用性。Hg 的吸附是由配位反应和静电吸引的联合过程调节的。所制备的多胺-三聚氰胺交联 CS 衍生物被发现是从水溶液和受污染的水中吸附捕获 Hg 离子的潜在吸附剂。
