Chan Kayee, Zinchenko Anatoly
Graduate School of Environmental Studies, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8601, Japan.
Graduate School of Environmental Studies, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8601, Japan.
Waste Manag. 2023 Jun 1;164:20-28. doi: 10.1016/j.wasman.2023.03.037. Epub 2023 Apr 4.
The progressive accumulation of discarded plastic in the environment demands further development of waste management of plastic waste and conversion technologies of such waste to value-added materials. Recently, the conversion of plastic waste to functional materials via chemical recycling has attracted considerable attention. In this report, plastic waste (PET) was utilized for the preparation of a hydrogel-based catalyst via a cross-linking reaction of PET-derived oligo(terephthalamide)s followed by the electroless metallization. The polymeric matrix of PET-derived hydrogel plays multiple roles of (i) an adsorption media for noble metal ions such as Au and Ag, (ii) a reducing agent of Au and Ag ions to Au and Ag, and (iii) a matrix for the controlled growth of Au and Ag nanoparticles (AuNPs and AgNPs). The obtained hybrid hydrogels after metallization contained well-dispersed AuNPs and AgNPs of 6.1 ± 3.7 nm or 6.1 ± 1.4 nm size, respectively. The catalytic activities of the hybrid hydrogels with metal nanoparticles were studied in a model system of p-nitrophenol reduction in an aqueous solution. The hybrid materials of both Au@hydrogel and Ag@hydrogel were catalytically active for the reduction of p-nitrophenol, obeying the first-order kinetics. Importantly, the AuNPs or AgNPs in the hydrogel matrix preserved the original catalytic activity after multiple p-nitrophenol reduction reactions, showing a promising reusability of the catalysts. The proposed here approach aims to broaden the scope of conversion routes of plastic waste to value-added materials as well as to develop new types of polymeric matrices for templating and growth of metal nanoparticles for catalytic applications.
环境中废弃塑料的不断累积，要求进一步发展塑料垃圾的废物管理以及将此类垃圾转化为增值材料的技术。最近，通过化学回收将塑料垃圾转化为功能材料引起了广泛关注。在本报告中，塑料垃圾（聚对苯二甲酸乙二酯，PET）通过PET衍生的低聚（对苯二甲酰胺）的交联反应，随后进行化学镀金属，被用于制备水凝胶基催化剂。PET衍生水凝胶的聚合物基质发挥多种作用：（i）作为金和银等贵金属离子的吸附介质；（ii）作为金和银离子还原为金和银的还原剂；（iii）作为金和银纳米颗粒（金纳米颗粒和银纳米颗粒）可控生长的基质。金属化后得到的杂化水凝胶分别包含尺寸为6.1±3.7纳米或6.1±1.4纳米的均匀分散的金纳米颗粒和银纳米颗粒。在水溶液中对硝基苯酚还原的模型体系中研究了含有金属纳米颗粒的杂化水凝胶的催化活性。金@水凝胶和银@水凝胶这两种杂化材料对硝基苯酚的还原均具有催化活性，遵循一级动力学。重要的是，水凝胶基质中的金纳米颗粒或银纳米颗粒在多次对硝基苯酚还原反应后仍保留其原始催化活性，显示出该催化剂具有良好的可重复使用性。本文提出的方法旨在拓宽塑料垃圾转化为增值材料的转化途径范围，并开发用于催化应用中金属纳米颗粒模板化和生长的新型聚合物基质。
