Department of Chemistry "Giacomo Ciamician", University of Bologna, Technopole of Rimini, Via Dario Campana 71, 47922 Rimini, Italy.
Department of Industrial Chemistry "Toso Montanari", University of Bologna, Viale Risorgimento 4, 40136 Bologna, Italy.
Int J Mol Sci. 2023 Sep 22;24(19):14415. doi: 10.3390/ijms241914415.
The search for alternative ways to give a second life to materials paved the way for detailed investigation into three silica-polyethylenimine (Si-PEI) materials for the purpose of CO adsorption in carbon capture and storage. A solvent extraction procedure was investigated to recover degraded PEIs and silica, and concomitantly, pyrolysis was evaluated to obtain valuable chemicals such as alkylated pyrazines. An array of thermal (TGA, Py-GC-MS), mechanical (rheology), and spectroscopical (ATR-FTIR, H-C-NMR) methods were applied to PEIs extracted with methanol to determine the relevant physico-chemical features of these polymers when subjected to degradation after use in CO capture. Proxies of degradation associated with the plausible formation of urea/carbamate moieties were revealed by Py-GC-MS, NMR, and ATR-FTIR. The yield of alkylpyrazines estimated by Py-GC-MS highlighted the potential of exhausted PEIs as possibly valuable materials in other applications.
寻找使材料焕发第二次生命的替代方法，为详细研究三种用于碳捕获和储存中 CO 吸附的硅-聚乙烯亚胺 (Si-PEI) 材料铺平了道路。研究了溶剂萃取程序以回收降解的 PEI 和二氧化硅，并同时评估了热解以获得有价值的化学品，如烷基吡嗪。采用一系列热（TGA、Py-GC-MS）、机械（流变学）和光谱（ATR-FTIR、H-C-NMR）方法对用甲醇提取的 PEI 进行了分析，以确定这些聚合物在用于 CO 捕获后发生降解时的相关物理化学特性。通过 Py-GC-MS、NMR 和 ATR-FTIR 揭示了与可能形成脲/氨基甲酸酯基团相关的降解指标。通过 Py-GC-MS 估算的烷基吡嗪产率突出了用过的 PEI 作为其他应用中可能有价值的材料的潜力。
