Opening up ZSM-5 Hierarchical Zeolite’s Porosity through Sequential Treatments for Improved Low-Density Polyethylene Cracking
An adequately tuned acid wash of hierarchical ZSM-5 zeolites offers a levelling up in the catalytic cracking of low-density polyethylene. Identification of crucial and limiting factors governing the activity of the zeolite was extended with studies about the accessibility of acid sites, nature of th...
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| Format: | Article |
| Language: | English |
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MDPI AG
2020-06-01
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| Series: | Molecules |
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| Online Access: | https://www.mdpi.com/1420-3049/25/12/2878 |
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| author | Karolina A. Tarach Kamila Pyra Kinga Góra-Marek |
| author_facet | Karolina A. Tarach Kamila Pyra Kinga Góra-Marek |
| author_sort | Karolina A. Tarach |
| collection | DOAJ |
| description | An adequately tuned acid wash of hierarchical ZSM-5 zeolites offers a levelling up in the catalytic cracking of low-density polyethylene. Identification of crucial and limiting factors governing the activity of the zeolite was extended with studies about the accessibility of acid sites, nature of the realuminated layer and role of Lewis acid sites. The sequential treatment of a ZSM-5 zeolite offered enhanced activity in low-density polyethylene (LDPE) cracking at low and high conversions, as confirmed by a decrease in the temperatures needed to reach 20% and 80% conversion (T<sub>20</sub> and T<sub>80</sub>, respectively). A linear dependence of the T<sub>80</sub> on the coupled IHF (indexed hierarchy factor) and AF<sub>B</sub> (accessibility factor) highlighted the importance of the textural and acidic parameters in the catalytic cracking of LDPE. <i>Operando</i> FT-IR-GC studies confirmed a higher fraction of short-chain hydrocarbons (C<sub>3</sub>–C<sub>5</sub>) in the product distribution of hierarchical catalysts resulting from the effective polymer cracking in easily accessible pores. |
| first_indexed | 2024-03-10T18:57:21Z |
| format | Article |
| id | doaj.art-74385a1859144c17911ddfa0ae3e9c7c |
| institution | Directory Open Access Journal |
| issn | 1420-3049 |
| language | English |
| last_indexed | 2024-03-10T18:57:21Z |
| publishDate | 2020-06-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Molecules |
| spelling | doaj.art-74385a1859144c17911ddfa0ae3e9c7c2023-11-20T04:38:52ZengMDPI AGMolecules1420-30492020-06-012512287810.3390/molecules25122878Opening up ZSM-5 Hierarchical Zeolite’s Porosity through Sequential Treatments for Improved Low-Density Polyethylene CrackingKarolina A. Tarach0Kamila Pyra1Kinga Góra-Marek2Faculty of Chemistry, Jagiellonian University in Kraków, 2 Gronostajowa St., 30–87 Kraków, PolandFaculty of Chemistry, Jagiellonian University in Kraków, 2 Gronostajowa St., 30–87 Kraków, PolandFaculty of Chemistry, Jagiellonian University in Kraków, 2 Gronostajowa St., 30–87 Kraków, PolandAn adequately tuned acid wash of hierarchical ZSM-5 zeolites offers a levelling up in the catalytic cracking of low-density polyethylene. Identification of crucial and limiting factors governing the activity of the zeolite was extended with studies about the accessibility of acid sites, nature of the realuminated layer and role of Lewis acid sites. The sequential treatment of a ZSM-5 zeolite offered enhanced activity in low-density polyethylene (LDPE) cracking at low and high conversions, as confirmed by a decrease in the temperatures needed to reach 20% and 80% conversion (T<sub>20</sub> and T<sub>80</sub>, respectively). A linear dependence of the T<sub>80</sub> on the coupled IHF (indexed hierarchy factor) and AF<sub>B</sub> (accessibility factor) highlighted the importance of the textural and acidic parameters in the catalytic cracking of LDPE. <i>Operando</i> FT-IR-GC studies confirmed a higher fraction of short-chain hydrocarbons (C<sub>3</sub>–C<sub>5</sub>) in the product distribution of hierarchical catalysts resulting from the effective polymer cracking in easily accessible pores.https://www.mdpi.com/1420-3049/25/12/2878hierarchical zeolitesacid-washLewis acid sites<i>operando</i> spectroscopyLDPE crackingrealumination |
| spellingShingle | Karolina A. Tarach Kamila Pyra Kinga Góra-Marek Opening up ZSM-5 Hierarchical Zeolite’s Porosity through Sequential Treatments for Improved Low-Density Polyethylene Cracking Molecules hierarchical zeolites acid-wash Lewis acid sites <i>operando</i> spectroscopy LDPE cracking realumination |
| title | Opening up ZSM-5 Hierarchical Zeolite’s Porosity through Sequential Treatments for Improved Low-Density Polyethylene Cracking |
| title_full | Opening up ZSM-5 Hierarchical Zeolite’s Porosity through Sequential Treatments for Improved Low-Density Polyethylene Cracking |
| title_fullStr | Opening up ZSM-5 Hierarchical Zeolite’s Porosity through Sequential Treatments for Improved Low-Density Polyethylene Cracking |
| title_full_unstemmed | Opening up ZSM-5 Hierarchical Zeolite’s Porosity through Sequential Treatments for Improved Low-Density Polyethylene Cracking |
| title_short | Opening up ZSM-5 Hierarchical Zeolite’s Porosity through Sequential Treatments for Improved Low-Density Polyethylene Cracking |
| title_sort | opening up zsm 5 hierarchical zeolite s porosity through sequential treatments for improved low density polyethylene cracking |
| topic | hierarchical zeolites acid-wash Lewis acid sites <i>operando</i> spectroscopy LDPE cracking realumination |
| url | https://www.mdpi.com/1420-3049/25/12/2878 |
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