Yu Hao, Idesaki Akira, Yoshimura Kimio, Maekawa Yasunari
Takasaki Institute of Advanced Quantum Science (TIAQ), National Institutes for Quantum Science and Technology (QST), 1233 Watanuki-machi, Takasaki, Gunma 370-1292, Japan.
ACS Omega. 2025 Jun 29;10(27):28848-28856. doi: 10.1021/acsomega.4c11623. eCollection 2025 Jul 15.
This study investigated the impact of a Ni-complex catalyst on the thermal decomposition of irradiated poly-(tetrafluoroethylene) (PTFE) through thermogravimetric analysis and spectroscopic techniques. This catalyst, comprising Ni and NiO particles on a microporous SiO/AlO support, was incorporated into PTFE powder via mechanical grinding. The Ni-loaded PTFE exhibited nearly 50% weight loss at temperatures 370-400 °C, which is 153-123 °C lower than the decomposition temperature of untreated PTFE (523 °C). The thermal stability of PTFE declines significantly above its melting point. Following electron beam irradiation, approximately half of the irradiated PTFE residue was degassed at relatively low temperatures (100-140 °C), likely due to thermal reactions of the decomposed products or chemically modified PTFE components. FTIR and XPS analyses of the Ni-loaded PTFE residue revealed that both the Ni catalyst and irradiation promoted C-F bond cleavage along with the formation and breakdown of oxidized PTFE fragments and fluorocarbons (C F O ). Additionally, the Ni catalyst enhanced PTFE oxidation, promoting the conversion of oxidized PTFE moieties to gaseous products such as CO, CO, and COF. Furthermore, the catalyst supplies oxygen for oxidation and decomposes unoxidized PTFE components during irradiation and subsequent thermal treatment. The combined effects of the Ni catalyst and irradiation notably reduced the thermal decomposition temperature of PTFE, showing great potential for expansion to applications involving the recycling of all per- and polyfluoroalkyl substances.
本研究通过热重分析和光谱技术，研究了镍配合物催化剂对辐照聚四氟乙烯（PTFE）热分解的影响。该催化剂由负载在微孔SiO/AlO载体上的镍和氧化镍颗粒组成，通过机械研磨将其掺入PTFE粉末中。负载镍的PTFE在370-400°C的温度下表现出近50%的重量损失，这比未处理的PTFE的分解温度（523°C）低153-123°C。PTFE的热稳定性在其熔点以上显著下降。电子束辐照后，大约一半的辐照PTFE残渣在相对较低的温度（100-140°C）下脱气，这可能是由于分解产物的热反应或化学改性的PTFE组分所致。对负载镍的PTFE残渣的FTIR和XPS分析表明，镍催化剂和辐照均促进了C-F键的断裂，同时伴随着氧化PTFE片段和碳氟化合物（C F O ）的形成和分解。此外，镍催化剂增强了PTFE的氧化，促进了氧化PTFE部分转化为气态产物，如CO、CO和COF。此外，催化剂在辐照和后续热处理过程中为氧化提供氧气，并分解未氧化的PTFE组分。镍催化剂和辐照的综合作用显著降低了PTFE的热分解温度，在涉及所有全氟和多氟烷基物质回收利用的应用扩展方面显示出巨大潜力。
