Matsumura Mei, Inagaki Jun, Yamada Ryo, Tashiro Natsuko, Ito Katsuya, Sasaki Mitsuru
Tsuruga Films Technology Center, Toyobo Co., Ltd., 10-24 Toyo-cho, Tsuruga, Fukui 914-8550, Japan.
Frontier Materials Technology Center, Toyobo Co., Ltd., 2-1-1 Katata, Otsu, Shiga 520-0292, Japan.
ACS Omega. 2024 Mar 4;9(11):13125-13133. doi: 10.1021/acsomega.3c09350. eCollection 2024 Mar 19.
The production of textile products is increasing annually, and most of them are disposed of after use without recycling. One of the reasons for the low recycling percentage of discarded textile products is the difficulty of recycling as a single material as these products are produced from a combination of two or more materials. Therefore, a technology to separate materials is necessary to improve the recycling percentage of textile products and to build a sustainable recycling industry. The aim of this study was to separate the most common combination of materials, such as cotton/polyester, in an environmentally friendly technique using hydrothermal treatment with only water. Herein, the optimal treatment conditions for blended fabrics in a high-pressure reactor were studied. Moreover, cotton could be separated by treating the fabrics at 220 to 230 °C for 10 min while maintaining the shape of the fabrics. Additionally, polyester showed a melting point, confirming that polyester could be separated without decomposition into monomers, unlike common chemical recycling. The strength of the separated cotton and the molecular weight of the polyester were evaluated, and a kinetic analysis of the changes due to the treatment was conducted. The activation energy obtained from the Arrhenius plot was 111.8 kJ/mol for PET, which was smaller than 142.6 kJ/mol for cotton. This indicates that the decrease in the molecular weight of PET is more likely to occur than the change in the strength of cotton, suggesting the possibility of separating the materials from the kinetic analysis.
纺织品的产量逐年增加，其中大部分在使用后未经回收就被丢弃了。废弃纺织品回收率低的原因之一是这些产品由两种或更多种材料组合而成，作为单一材料进行回收存在困难。因此，需要一种材料分离技术来提高纺织品的回收率，并建立可持续的回收产业。本研究的目的是采用仅用水进行水热处理的环保技术，分离最常见的材料组合，如棉/聚酯。在此，研究了高压反应器中混纺织物的最佳处理条件。此外，通过在220至230°C下处理织物10分钟，同时保持织物形状，可以分离出棉花。此外，聚酯显示出熔点，这证实了聚酯可以在不分解成单体的情况下被分离，这与常见的化学回收不同。对分离出的棉花的强度和聚酯的分子量进行了评估，并对处理引起的变化进行了动力学分析。从阿伦尼乌斯图获得的PET的活化能为111.8 kJ/mol，低于棉花的142.6 kJ/mol。这表明PET分子量的降低比棉花强度的变化更有可能发生，这从动力学分析表明了分离材料的可能性。
