Lu Yao , Jianhua Zhu , Shuyuan Li , Yue Ma , Changtao Yue
{"title":"Analysis of liquid products and mechanism of thermal/catalytic pyrolysis of polypropylene","authors":"Lu Yao , Jianhua Zhu , Shuyuan Li , Yue Ma , Changtao Yue","doi":"10.1016/j.polymdegradstab.2025.111338","DOIUrl":null,"url":null,"abstract":"<div><div>Rapid thermal and catalytic pyrolysis of polypropylene (PP) were carried out using Py-GC/MS. The distribution of products of rapid pyrolysis and the influence of FCC catalyst on pyrolysate production were studied both qualitatively and quantitatively at the temperature of 500 °C. The corresponding reaction pathways were suggested based on the experimental results. The results showed that the olefin content of PP cracking products exceeded 99 wt. %, which were monoolefines with carbon number of 3n and diolefins with carbon number of 3n+1, respectively, and only a very small amount of alkanes. The catalyst promoted the formation of monolefine and decreased the content of diolefin. With the addition of catalyst, the content of small molecular weight monolefine between C9 and C21 increased by 13.6 wt. %, while the diolefin content of C15+ decreased to varying degrees. The thermal and catalytic pyrolysis of PP can be reasonably explained using free radical mechanism and carbonium ion mechanism, respectively.</div></div>","PeriodicalId":406,"journal":{"name":"Polymer Degradation and Stability","volume":"238 ","pages":"Article 111338"},"PeriodicalIF":6.3000,"publicationDate":"2025-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Polymer Degradation and Stability","FirstCategoryId":"92","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0141391025001685","RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"POLYMER SCIENCE","Score":null,"Total":0}
引用次数: 0
Abstract
Rapid thermal and catalytic pyrolysis of polypropylene (PP) were carried out using Py-GC/MS. The distribution of products of rapid pyrolysis and the influence of FCC catalyst on pyrolysate production were studied both qualitatively and quantitatively at the temperature of 500 °C. The corresponding reaction pathways were suggested based on the experimental results. The results showed that the olefin content of PP cracking products exceeded 99 wt. %, which were monoolefines with carbon number of 3n and diolefins with carbon number of 3n+1, respectively, and only a very small amount of alkanes. The catalyst promoted the formation of monolefine and decreased the content of diolefin. With the addition of catalyst, the content of small molecular weight monolefine between C9 and C21 increased by 13.6 wt. %, while the diolefin content of C15+ decreased to varying degrees. The thermal and catalytic pyrolysis of PP can be reasonably explained using free radical mechanism and carbonium ion mechanism, respectively.
期刊介绍:
Polymer Degradation and Stability deals with the degradation reactions and their control which are a major preoccupation of practitioners of the many and diverse aspects of modern polymer technology.
Deteriorative reactions occur during processing, when polymers are subjected to heat, oxygen and mechanical stress, and during the useful life of the materials when oxygen and sunlight are the most important degradative agencies. In more specialised applications, degradation may be induced by high energy radiation, ozone, atmospheric pollutants, mechanical stress, biological action, hydrolysis and many other influences. The mechanisms of these reactions and stabilisation processes must be understood if the technology and application of polymers are to continue to advance. The reporting of investigations of this kind is therefore a major function of this journal.
However there are also new developments in polymer technology in which degradation processes find positive applications. For example, photodegradable plastics are now available, the recycling of polymeric products will become increasingly important, degradation and combustion studies are involved in the definition of the fire hazards which are associated with polymeric materials and the microelectronics industry is vitally dependent upon polymer degradation in the manufacture of its circuitry. Polymer properties may also be improved by processes like curing and grafting, the chemistry of which can be closely related to that which causes physical deterioration in other circumstances.