Deactivation and Regeneration of Zeolite Catalysts Used in Pyrolysis of Plastic Wastes—A Process and Analytical Review
In catalytic industrial processes, coke deposition remains a major drawback for solid catalysts use as it causes catalyst deactivation. Extensive study of this phenomenon over the last decades has provided a better understanding of coke behavior in a great number of processes. Among them, catalytic...
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| Format: | Article |
| Language: | English |
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MDPI AG
2021-06-01
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| Series: | Catalysts |
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| Online Access: | https://www.mdpi.com/2073-4344/11/7/770 |
| _version_ | 1797528798412931072 |
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| author | Vivien Daligaux Romain Richard Marie-Hélène Manero |
| author_facet | Vivien Daligaux Romain Richard Marie-Hélène Manero |
| author_sort | Vivien Daligaux |
| collection | DOAJ |
| description | In catalytic industrial processes, coke deposition remains a major drawback for solid catalysts use as it causes catalyst deactivation. Extensive study of this phenomenon over the last decades has provided a better understanding of coke behavior in a great number of processes. Among them, catalytic pyrolysis of plastics, which has been identified as a promising process for waste revalorization, is given particular attention in this paper. Combined economic and environmental concerns rose the necessity to restore catalytic activity by recovering deactivated catalysts. Consequently, various regeneration processes have been investigated over the years and development of an efficient and sustainable process remains an industrial challenge. Coke removal can be achieved via several chemical processes, such as oxidation, gasification, and hydrogenation. This review focuses on oxidative treatments for catalyst regeneration, covering the current progress of oxidation treatments and presenting advantages and drawbacks for each method. Molecular oxidation with oxygen and ozone, as well as advanced oxidation processes with the formation of OH radicals, are detailed to provide a deep understanding of the mechanisms and kinetics involved (direct and indirect oxidation, reaction rates and selectivity, diffusion, and mass transfer). Finally, this paper summarizes all relevant analytical techniques that can be used to characterize deactivated and regenerated solid catalysts: XRD, N<sub>2</sub> adsorption-desorption, SEM, NH<sub>3</sub>-TPD, elemental analysis, IR. Analytical techniques are classified according to the type of information they provide, such as structural characteristics, elemental composition, or chemical properties. In function of the investigated property, this overall tool is useful and easy-to-use to determine the adequate analysis. |
| first_indexed | 2024-03-10T10:04:31Z |
| format | Article |
| id | doaj.art-5d0c5642f9774d80ad98079e0067b2d1 |
| institution | Directory Open Access Journal |
| issn | 2073-4344 |
| language | English |
| last_indexed | 2024-03-10T10:04:31Z |
| publishDate | 2021-06-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Catalysts |
| spelling | doaj.art-5d0c5642f9774d80ad98079e0067b2d12023-11-22T01:41:18ZengMDPI AGCatalysts2073-43442021-06-0111777010.3390/catal11070770Deactivation and Regeneration of Zeolite Catalysts Used in Pyrolysis of Plastic Wastes—A Process and Analytical ReviewVivien Daligaux0Romain Richard1Marie-Hélène Manero2Laboratoire de Génie Chimique, Université de Toulouse, CNRS, INPT, UPS, F-31030 Toulouse, FranceLaboratoire de Génie Chimique, Université de Toulouse, CNRS, INPT, UPS, F-31030 Toulouse, FranceLaboratoire de Génie Chimique, Université de Toulouse, CNRS, INPT, UPS, F-31030 Toulouse, FranceIn catalytic industrial processes, coke deposition remains a major drawback for solid catalysts use as it causes catalyst deactivation. Extensive study of this phenomenon over the last decades has provided a better understanding of coke behavior in a great number of processes. Among them, catalytic pyrolysis of plastics, which has been identified as a promising process for waste revalorization, is given particular attention in this paper. Combined economic and environmental concerns rose the necessity to restore catalytic activity by recovering deactivated catalysts. Consequently, various regeneration processes have been investigated over the years and development of an efficient and sustainable process remains an industrial challenge. Coke removal can be achieved via several chemical processes, such as oxidation, gasification, and hydrogenation. This review focuses on oxidative treatments for catalyst regeneration, covering the current progress of oxidation treatments and presenting advantages and drawbacks for each method. Molecular oxidation with oxygen and ozone, as well as advanced oxidation processes with the formation of OH radicals, are detailed to provide a deep understanding of the mechanisms and kinetics involved (direct and indirect oxidation, reaction rates and selectivity, diffusion, and mass transfer). Finally, this paper summarizes all relevant analytical techniques that can be used to characterize deactivated and regenerated solid catalysts: XRD, N<sub>2</sub> adsorption-desorption, SEM, NH<sub>3</sub>-TPD, elemental analysis, IR. Analytical techniques are classified according to the type of information they provide, such as structural characteristics, elemental composition, or chemical properties. In function of the investigated property, this overall tool is useful and easy-to-use to determine the adequate analysis.https://www.mdpi.com/2073-4344/11/7/770plastic wasterecyclingcatalytic pyrolysisregenerationzeolite catalystscoke |
| spellingShingle | Vivien Daligaux Romain Richard Marie-Hélène Manero Deactivation and Regeneration of Zeolite Catalysts Used in Pyrolysis of Plastic Wastes—A Process and Analytical Review Catalysts plastic waste recycling catalytic pyrolysis regeneration zeolite catalysts coke |
| title | Deactivation and Regeneration of Zeolite Catalysts Used in Pyrolysis of Plastic Wastes—A Process and Analytical Review |
| title_full | Deactivation and Regeneration of Zeolite Catalysts Used in Pyrolysis of Plastic Wastes—A Process and Analytical Review |
| title_fullStr | Deactivation and Regeneration of Zeolite Catalysts Used in Pyrolysis of Plastic Wastes—A Process and Analytical Review |
| title_full_unstemmed | Deactivation and Regeneration of Zeolite Catalysts Used in Pyrolysis of Plastic Wastes—A Process and Analytical Review |
| title_short | Deactivation and Regeneration of Zeolite Catalysts Used in Pyrolysis of Plastic Wastes—A Process and Analytical Review |
| title_sort | deactivation and regeneration of zeolite catalysts used in pyrolysis of plastic wastes a process and analytical review |
| topic | plastic waste recycling catalytic pyrolysis regeneration zeolite catalysts coke |
| url | https://www.mdpi.com/2073-4344/11/7/770 |
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