Xi Luo, Jiahui Zhan, Qingqing Mei and Shicheng Zhang
{"title":"Selective oxidative upgrade of waste polystyrene plastics by nitric acid to produce benzoic acid†","authors":"Xi Luo, Jiahui Zhan, Qingqing Mei and Shicheng Zhang","doi":"10.1039/D3GC00865G","DOIUrl":null,"url":null,"abstract":"<p >Polystyrene plastic is a widely used artificial material, but there is still no efficient, economic or environmentally friendly recycling method for waste polystyrene plastic, which has caused serious environmental pollution and a waste of resources. Herein, the method of nitric acid oxidative upgrade is used to convert polystyrene plastic into a high-value chemical raw material, benzoic acid. The yield can reach nearly 90% at 180 °C within 3 h, and the purity of the product is more than 95%. In this process, nitric acid is decomposed by heat to generate nitrogen dioxide and oxygen, which react with the carbon-centered radicals formed at weak sites on the long chain of polystyrene and further generate peroxy radicals and hydroxyl radicals. The formation of oxygen-containing functional groups promoted the fracture of the C–C bond and eventually formed benzoic acid. In addition, this method also has good treatment effects on real-life polystyrene plastic products. This research provides a new method for the recycling and high-value utilization of waste polystyrene plastics. The intrinsic material value of polymers can be maintained by recycling functional chemicals through oxidative upgrade.</p>","PeriodicalId":78,"journal":{"name":"Green Chemistry","volume":" 17","pages":" 6717-6727"},"PeriodicalIF":9.3000,"publicationDate":"2023-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Green Chemistry","FirstCategoryId":"92","ListUrlMain":"https://pubs.rsc.org/en/content/articlelanding/2023/gc/d3gc00865g","RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"CHEMISTRY, MULTIDISCIPLINARY","Score":null,"Total":0}
引用次数: 0
Abstract
Polystyrene plastic is a widely used artificial material, but there is still no efficient, economic or environmentally friendly recycling method for waste polystyrene plastic, which has caused serious environmental pollution and a waste of resources. Herein, the method of nitric acid oxidative upgrade is used to convert polystyrene plastic into a high-value chemical raw material, benzoic acid. The yield can reach nearly 90% at 180 °C within 3 h, and the purity of the product is more than 95%. In this process, nitric acid is decomposed by heat to generate nitrogen dioxide and oxygen, which react with the carbon-centered radicals formed at weak sites on the long chain of polystyrene and further generate peroxy radicals and hydroxyl radicals. The formation of oxygen-containing functional groups promoted the fracture of the C–C bond and eventually formed benzoic acid. In addition, this method also has good treatment effects on real-life polystyrene plastic products. This research provides a new method for the recycling and high-value utilization of waste polystyrene plastics. The intrinsic material value of polymers can be maintained by recycling functional chemicals through oxidative upgrade.
期刊介绍:
Green Chemistry is a journal that provides a unique forum for the publication of innovative research on the development of alternative green and sustainable technologies. The scope of Green Chemistry is based on the definition proposed by Anastas and Warner (Green Chemistry: Theory and Practice, P T Anastas and J C Warner, Oxford University Press, Oxford, 1998), which defines green chemistry as the utilisation of a set of principles that reduces or eliminates the use or generation of hazardous substances in the design, manufacture and application of chemical products. Green Chemistry aims to reduce the environmental impact of the chemical enterprise by developing a technology base that is inherently non-toxic to living things and the environment. The journal welcomes submissions on all aspects of research relating to this endeavor and publishes original and significant cutting-edge research that is likely to be of wide general appeal. For a work to be published, it must present a significant advance in green chemistry, including a comparison with existing methods and a demonstration of advantages over those methods.