Park Sung-Sil, Lee Yun-Seok, Lee Seung-Woo, Repo Eveliina, Kim Tae-Hyun, Park Yuri, Hwang Yuhoon
Department of Environmental Engineering, Seoul National University of Science and Technology, Seoul 01811, Republic of Korea.
Department of Fine Chemistry, Seoul National University of Science and Technology, Seoul 01811, Republic of Korea.
Polymers (Basel). 2023 Jan 4;15(2):269. doi: 10.3390/polym15020269.
The structured adsorption filter material is one of the ways to enhance the practical applicability of powdered adsorbents, which have limitations in the real water treatment process due to difficulty in the separation process. In this study, three-dimensional (3D) printing technology was applied to prepare filter materials for water treatment processes. A 3D-printed graphene-oxide (GO)-based adsorbent is prepared on a polylactic acid (PLA) scaffold. The surface of the PLA scaffold was modified by subjecting it to strong alkaline or organic solvent treatment to enhance GO doping for realizing effective adsorption of cationic dye solutions. When subjected to 95% acetone treatment, the structural properties of PLA changed, and particularly, two main hydrophilic functional groups (carboxylic acids and hydroxyls) were newly formed on the PLA through cleavage of the ester bond of the aliphatic polyester. Owing to these changes, the roughness of the PLA surface increased, and its tensile strength decreased. Meanwhile, its surface was doped mainly with GO, resulting in approximately 75% methylene blue (MB) adsorption on the 3D-printed GO-based PLA filter. Based on the established optimal pretreatment conditions, a kinetic MB sorption study and an isotherm study were conducted to evaluate the 3D-printed GO-based PLA filter. The pseudo-second-order model yielded the best fit, and the MB adsorption was better fitted to the Langmuir isotherm. These results suggested that chemical adsorption was the main driver of the reaction, and monolayer sorption occurred on the adsorbent surface. The results of this study highlight the importance of PLA surface modification in enhancing GO doping and achieving effective MB adsorption in aqueous solutions. Ultimately, this study highlights the potential of using 3D printing technology to fabricate the components required for implementing water treatment processes.
结构化吸附过滤材料是增强粉末状吸附剂实际适用性的方法之一，粉末状吸附剂在实际水处理过程中因分离过程困难而存在局限性。在本研究中，应用三维（3D）打印技术制备用于水处理过程的过滤材料。在聚乳酸（PLA）支架上制备了一种3D打印的基于氧化石墨烯（GO）的吸附剂。通过对PLA支架进行强碱或有机溶剂处理来修饰其表面，以增强GO掺杂，从而实现对阳离子染料溶液的有效吸附。当进行95%丙酮处理时，PLA的结构性质发生变化，特别是通过脂肪族聚酯酯键的断裂在PLA上新形成了两个主要的亲水性官能团（羧酸和羟基）。由于这些变化，PLA表面的粗糙度增加，其拉伸强度降低。同时，其表面主要被GO掺杂，使得基于3D打印的GO-PLA过滤器对亚甲基蓝（MB）的吸附率约为75%。基于所建立的最佳预处理条件，进行了MB吸附动力学研究和等温线研究，以评估基于3D打印的GO-PLA过滤器。准二级模型拟合效果最佳，MB吸附更好地符合朗缪尔等温线。这些结果表明化学吸附是反应的主要驱动力，且在吸附剂表面发生单层吸附。本研究结果突出了PLA表面改性在增强GO掺杂和实现水溶液中有效MB吸附方面的重要性。最终，本研究突出了使用3D打印技术制造实施水处理过程所需组件的潜力。
