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Continuous flow pyrolysis of virgin and waste polyolefins:a comparative study,process optimization and product characterization

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Frontiers of Chemical Science and Engineering 2024年第6期18卷 133-149页

作者： Ecrin Ekici Güray Yildiz Magdalena Joka Yildiz Monika Kalinowska ErolŞeker Jiawei Wang Karlsruhe Institute of Technology Institute of Catalysis Research and TechnologyEggenstein-Leopoldshafen 76344Germany Izmir Institute of Technology Faculty of EngineeringDepartment of Energy Systems EngineeringIzmir 35430Türkiye Department of Materials Engineering and Production Faculty of Mechanical EngineeringBialystok University of TechnologyBialystok 15-351Poland Department of Agricultural and Food Engineering and Environmental Development Institute of Civil Engineering and EnergeticsFaculty of Civil Engineering and Environmental SciencesBialystok University of Technology15-351 BialystokPoland Department of Chemistry Biology and BiotechnologyInstitute of Civil Engineering and EnergeticsFaculty of Civil Engineering and Environmental SciencesBialystok University of TechnologyBialystok 15-351Poland Izmir Institute of Technology Faculty of EngineeringDepartment of Chemical EngineeringIzmir 35430Türkiye Energy and Bioproducts Research Institute(EBRI) Aston UniversityBirmingham B47ETUnited Kingdom

Under optimal process conditions,pyrolysis of polyolefins can yield ca.90 wt%of liquid product,i.e.,combination of light oil fraction and heavier *** this work,the experimental findings reported in a selected group of publications concerning the non-catalytic pyrolysis of polyolefins were collected,reviewed,and compared with the ones obtained in a continuously operated bench-scale pyrolysis *** process parameters were used for the pyrolysis of waste and virgin counterparts of high-density polyethylene,low-density polyethylene,polypropylene and a defined mixture of those(i.e.,25:25:50 wt%,respectively).To mitigate temperature drops and enhance heat transfer,an increased feed intake is employed to create a hot melt plastic *** 1.5 g·min^(-1) feed intake,1.1 L·min^(-1) nitrogen flow rate,and a moderate pyrolysis temperature of 450℃,the formation of light hydrocarbons was favored,while wax formation was limited for polypropylene-rich *** of virgin plastics yielded more liquid(maximum 73.3 wt%)than that of waste plastics(maximum 66 wt%).Blending polyethylenes with polypropylene favored the production of liquids and increased the formation of gasoline-range *** products were mainly composed of C3 hydrocarbons,and no hydrogen production was detected due to moderate pyrolysis temperature.

关键词： waste plastics polyolefins chemical recycling pyrolysis alternative fuels waste-to-energy

Combination of olefin insertion polymerization and olefin metathesis to extend the topology and composition of polyolefins

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Science China Chemistry 2020年第6期63卷 755-757页

作者： Tianwei Yan Damien Guironnet Department of Chemical and Biomolecular Engineering University of Illinois Urbana-ChampaignUrbanaIllinois 61801United States

Since Ziegler,Hogan and Banks’seminal discoveries for the catalytic polymerization of olefins,many generations of catalysts have been reported[1–5].These include the transition from the original heterogeneous cataly... 详细信息

关键词： polymerization metathesis polyolefins

Covalently Cross-Linked and Mechanochemiluminescent polyolefins Capable of Self-Healing and Self-Reporting

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CCS Chemistry 2021年第5期3卷 1316-1324页

作者： Yakui Deng Yuan Yuan Yulan Chen Tianjin Key Laboratory of MolecularOptoelectronic Science Department of ChemistryTianjin UniversityTianjin 300354

Compared with non-cross-linked and dynamically covalent polymers,covalently cross-linked networks are irreplaceableinmany areas;however,they aredifficult to repair once fractured,due to limited polymer chain diffusion after ***,the authors have reported a newkind of permanently cross-linked polyolefin,which when attached with amide side groups,yieldmechanically robust yet readily repairablematerials.A key is to use low cross-linking density,which enables satisfactory elasticity and chain mobility for thermodynamically favored *** key is to incorporate dense hydrogen bonds that can undergo reversible *** factors jointly promise polyolefin networks with good mechanical properties and self-healing performance(recovered spontaneously up to 96%of its original tensile strength).More importantly,by means of mechanochemiluminescence from 1,2-dioxetane,which serves as the cross-linker and built-in self-reporting stress probe,a microscopic evaluation of how the chain entanglement proceeds upon healing and how failure occurs in the network can be obtained.

关键词： self-healing self-reporting polyolefins covalently cross-linked mechanochemiluminescence

Enhancement on Hemilabile Phosphine-Amide Palladium and Nickel Catalysts for Ethylene(Co)Polymerization with Polar Monomers Using a Cyclizing Strategy

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Chinese Journal of Polymer Science 2022年第3期40卷 241-247,I0005页

作者： Lei Cui Yu-Kai Chu Da-Jun Liu Ying-Feng Han Hong-Liang Mu Zhong-Bao Jian State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China School of Chemistry and Environmental Engineering Changchun University of Science and TechnologyChangchun 130022China Key Laboratory of Synthetic and Natural Functional Molecule of the Ministry of Education College of Chemistry and Materials ScienceNorthwest UniversityXi’an 710127China

To address the issue of hemilabile catalyst in olefin polymerization catalysis, a cyclizing strategy was used to construct novel N-bridged phosphine-carbonyl palladium and nickel catalysts, resulting in improvements on ethylene(co)polymerizations. The N-bridged phosphinecarbonyl Pd catalysts(Pd1-Pd5) and Ni catalysts(Ni1-Ni5) bearing five-to eight-membered-ring structures were designed and *** performance for ethylene(co)polymerization became better as the size of N-containing bridge increased. The seven-membered-ring bridged catalysts Pd4 and Ni4 exhibited the best performance in terms of catalytic activity, polymer molecular weight and incorporation of acrylates and acrylic acid. The better performance of these catalysts bearing larger-size bridges was tentatively attributed to the methyleneinduced higher electron density around nitrogen, which strenghtens the coordination of carbonyl group to metal center, and also to the steric effect offered by this cyclization. This work provides a new strategy to enhance hemilabile polymerization catalysts.

关键词： polyolefins Cyclizing strategy Phosphine ligands Polar monomers Late transition metal catalysts

Beyond Conventional Degradation:Catalytic Solutions for Polyolefin Upcycling

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CCS Chemistry 2024年第2期6卷 313-333页

作者： Lan Gan Zhongwen Dong Haofeng Xu Huidong Lv Guixia Liu Fan Zhang Zheng Huang State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of SciencesShanghai 200032 School of Chemistry and Material Sciences Hangzhou Institute of Advanced StudyHangzhou 310024 National Engineering Laboratory of Eco-Friendly Polymeric Materials(Sichuan) College of ChemistrySichuan UniversityChengdu 610064

polyolefins(POs,i.e.,polyethylenes,ethylene/α-olefin copolymers,and polypropylenes)are the most ubiquitous synthetic macromolecular materials in modern *** widespread use and low recovery rate after extensive usage have caused significant resource waste and environmental *** recycling of POs provides an efficient approach to unravelling the polymer chain to various ***,conventional chemical recycling methods,including pyrolysis,hydrocracking,and oxidation,require high-energy input(typically>500℃)and/or the use of environmentally unfriendly chemicals,leading to complex product *** this minireview,based on recent representative works,we summarize and highlight catalytic strategies addressing these issues in PO recycling from two perspectives:(1)employing advanced catalysts or technique designs to overcome the challenges in conventional chemical deconstruction approaches;and(2)developing novel tandem/cascade catalytic systems for highly selective PO upcycling under relatively mild *** hope that this minireview will help researchers better understand the state of the art of PO chemical recycling and inspire more innovative and efficient ideas for this fast-developing field.

关键词： catalytic strategies chemical recycling deconstruction polyolefins upcycling

CO2-facilitated upcycling of polyolefin plastics to aromatics at low temperature

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National Science Review 2024年第5期11卷 236-243页

作者： Yi Ding Shuchi Zhang Cheng Liu Yu Shao Xiulian Pan Xinhe Bao State Key Laboratory of Catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences University of Chinese Academy of Sciences Department of Chemical Physics University of Science and Technology of China

Plastics are one of the most produced synthetic materials and largest commodities, used in numerous sectors of human life. To upcycle waste plastics into value-added chemicals is a global challenge. Despite significant progress in pyrolysis and hydrocracking, which mainly leads to the formation of pyrolysis oil,catalytic upcycling to value-added aromatics, including benzene, toluene and xylene（BTX）, in one step, is still limited by high reaction temperatures（>500°C） and a low yield. We report herein CO2-facilitated upcycling of polyolefins and their plastic products to aromatics below 300°C, enabled by a bifunctional Pt/Mn Ox-ZSM-5 catalyst. ZSM-5 catalyzes cracking of polyolefins and aromatization, generating hydrogen at the same time, while Pt/Mn Ox catalyzes the reaction of hydrogen with CO2, consequently driving the reaction towards aromatization. Isotope experiments reveal that 0.2 kg CO2is consumed per 1.0 kg polyethylene and 90% of the consumed CO2is incorporated into the aromatic products. Furthermore, this new process yields 0.63 kg aromatics（BTX accounting for 60%）, comparing favorably with the conventional pyrolysis or hydrocracking processes, which produce only 0.33 kg aromatics. In this way, both plastic waste and the greenhouse gas CO2are turned into carbon resources, providing a new strategy for combined waste plastics upcycling and carbon dioxide utilization.

关键词： polyolefins carbon dioxide aromatics upcycling bifunctional catalysis

Nanostructured Functional Thermoplastic Polymeric Materials Based on the Molecular Control of the Blending

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复旦学报（自然科学版） 2007年第5期46卷 634-页

作者： E.Passaglia M.Bertoldo S.Coiai S.Augier F.Ciardelli ICCOM-CNR Pisa Section PolyLab-CNR C.I.P.Porto Marghera Dipartimento di Chimica e Chimica Industriale Università di PisaVia Risorgimento 35Pisa 56126Italy

1 Results The development of the concepts of nanotechnology has given an important impact on the design of new polymer based materials which are in most cases characterized by a multiphase morphology. When at least one phase has nanometric dimension(s) the system can be considered as a nanocomposite where the interface is not only determining for the adhesion but also may play a role in some bulk properties. Indeed in nanostructured multiphase solids the interface is significant as a bulk component. The...

关键词： polyolefins nanocomposites confinement

Superhydrophobicity on Micro-and Nanostructured Polyolefin Surfaces:an Experimental and Theoretical Study

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复旦学报（自然科学版） 2007年第5期46卷 637-页

作者： Tapani A Pakkanen Esa Puukilainen Janne Hirvi Tiina Rasilainen Mika Suvanto Deparment of Chemistry University of Joensuu Joensuu FI-801018Finland

1 Results Simultaneous micro-and nanostructuring was prepared on polyolefin surfaces by injection *** molds were made of electropolished aluminum foil where the micropatterns were structured with a custom made *** were subsequently created on the molds by oxidizing the aluminum surface electrochemically in polyprotic *** preparation technique allowed simultaneous control of the dimensions of the micro-and *** has a remarkable effect on the contact angle...

关键词： polyolefins superhydrophobicity micro-and nanostructures molecular dynamics

具有热致和电致双重响应特性的三重形状记忆聚合物

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具有热致和电致双重响应特性的三重形状记忆聚合物