Agricultural Bio-Resources Research Institute, Fujian Academy of Agricultural Sciences, Fuzhou, Fujian 350003, PR China.
College of Food Science, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, PR China; China-Ireland International Cooperation Laboratory of Foods Material Science and Structural Design, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, PR China; Fujian Provincial Key Laboratory of Quality Science and Processing Technology in Special Starch, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, PR China.
Int J Biol Macromol. 2020 Jun 15;153:573-582. doi: 10.1016/j.ijbiomac.2020.03.024. Epub 2020 Mar 5.
A poly(gellan gum-co-acrylamide-co-acrylic acid) (GGDA) hydrogel was synthesized by modifying gellan gum (GG) with partly neutralized acrylic acid (AAc) and acrylamide (AAm) under the crosslinking agent trimethylolpropane triglycidyl ether. With the introduction of carboxyl and amino groups by the AAc and AAm, the GGDA showed better regularity than GG, leading to a more porous structure and higher thermal stability. Methylene blue (MB) was used as a model organic dye to evaluate the adsorption capacity of the GGDA. The GGDA exhibited excellent MB adsorption abilities and pH sensitivity. The pseudo-second-order and Freundlich isotherm models produced the best fits for the adsorption kinetics and adsorption equilibrium, respectively. The Gibbs free energy, enthalpy, and entropy of adsorption indicated that the adsorption was a spontaneous, exothermic, and entropy-decreasing process. The maximum equilibrium adsorption capacity of MB was 423.46 ± 13.60 mg/g. This pH-sensitive hydrogel is a potential alternative absorbent for organic dye removal in aqueous solutions.
一种聚（卡拉胶-co-丙烯酰胺-co-丙烯酸）（GGDA）水凝胶是通过部分中和的丙烯酸（AAc）和丙烯酰胺（AAm）改性卡拉胶（GG），在交联剂三羟甲基丙烷三缩水甘油醚的作用下合成的。通过 AAc 和 AAm 的引入羧基和氨基，GGDA 比 GG 更规则，导致更多孔的结构和更高的热稳定性。亚甲基蓝（MB）被用作模型有机染料来评估 GGDA 的吸附能力。GGDA 表现出优异的 MB 吸附能力和 pH 敏感性。准二级和 Freundlich 等温线模型分别对吸附动力学和吸附平衡产生了最佳拟合。吸附的吉布斯自由能、焓和熵表明吸附是一个自发的、放热的和熵减少的过程。MB 的最大平衡吸附容量为 423.46±13.60mg/g。这种 pH 敏感水凝胶是一种有潜力的替代吸附剂，用于去除水溶液中的有机染料。
