柠檬酸-氯化锌协同酸解分离废旧涤棉混纺织物

Separation of Waste Polyester/Cotton Blended Fabrics Using Synergistic Acidolysis of Citric Acid and Zinc Chloride

针对废旧涤棉织物的大量存在,且回收困难、混合再利用产物附加值低下等问题,利用柠檬酸和氯化锌酸解棉纤维,并探讨了分离的机理。当柠檬酸浓度为30%,氯化锌浓度为35%,温度为90℃,时间为3 h达到涤棉分离目的。纤维素回收率为84.1%,且依然保持纤维素I型的晶体结构,聚合度和结晶度分别下降了83.8%和27.3%。涤纶回收率为97.8%,在分离处理后几乎没有损伤。柠檬酸和氯化锌酸解体系可循环利用多次,实现了废旧涤棉混纺织物的分离回收。

The recycling process of waste polyester/cotton fabrics presents an enormous challenge due to a considerable quantity of waste,the intricate methodology and the minimal value of reused mixed products.The synergistic effect of citric acid and zinc chloride is utilized to effectively break cotton fibers while investigating the underlying mechanism of separation.By employing a concentration of 30%citric acid,35%zinc chloride,a temperature of 90°C,and 3 h,successful separation between polyester and cotton is achieved.The recovery rate of cellulose attains 84.1%,while retaining its crystalline structure characteristic of cellulose I.However,the degree of polymerization and crystallinity experience a decrease of 83.8%and 27.3%,respectively.Polyester fibers demonstrate a remarkable recovery rate of 97.8%,remaining largely undamaged throughout the separation process.The citric acid and zinc chloride acidolysis system can be recycled several times,enabling the separation and recovery of waste polyester/cotton blended fabrics.