The effect of ZSM-5 zeolite acidity on the catalytic degradation of high-density polyethylene using simultaneous DSC/TG analysis

Coelho, Ana; Costa, Luís; Marques, M. Manuel B.; Fonseca, Isabel; Lemos, M.A.N.D.A.; Lemos, F.

doi:10.1016/j.apcata.2011.11.010

Cited by 85 publications

(83 citation statements)

References 36 publications

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“…Thermogravimetric analysis of pyrolysis involves the thermal degradation of the sample in an inert atmosphere obtaining simultaneously the weight loss values of the samples with increasing temperature at a constant heating rate [4,21,31] . Most of the techniques that are used to monitor the reactions, both for the identification of products of the gas phase and by thermogravimetric analysis, will only detect the reaction when the molecules of the products become small enough to evaporate in the gas fraction and can be observed as gas fraction or by means of mass loss of the initial sample.…”

Section: Pyrolysismentioning

confidence: 99%

“…This occurs because the uncatalyzed thermal degradation gives rise to low molecular weight substances, however in a very wide range of products [13,15,16] . This method can be improved by the addition of catalysts, which will reduce the temperature and reaction time and allow the production of hydrocarbons with a higher added value, such as fuel oils and petrochemical feedstocks [4,11,[18][19][20][21] . That is, the use of catalysts gives an added value to the pyrolysis and cracking efficiency of these catalysts depends both on its chemical and physical characteristics.…”

Section: Introductionmentioning

confidence: 99%

“…This process can be thermal or catalytic and is a promising alternative that allows the conversion of polymers into gas and liquid hydrocarbons [4,15,16] .…”

Section: Introductionmentioning

confidence: 99%

“…It is necessary for more sustainable solutions that incineration and disposal in landfills are researched and developed [4] . Thus, much research in the area of recycling and reuse of these post-consumed polymers have been carried out in order to produce raw materials and energy [1,3,7] .…”

Section: Introductionmentioning

confidence: 99%

“…As a result of this contribution, a large amount of plastic waste is generated due to the increase in its production each year. This increase in the amount of waste does cause some environmental problems, since plastics do not degrade quickly and can remain in the environment for a long time [1][2][3][4][5] . A large part of this waste is disposed of in landfills or is incinerated [6,7] .…”

Section: Introductionmentioning

confidence: 99%

See 4 more Smart Citations

Thermal and catalytic pyrolysis of plastic waste

2016

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Section: Pyrolysismentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

“…This process can be thermal or catalytic and is a promising alternative that allows the conversion of polymers into gas and liquid hydrocarbons [4,15,16] .…”

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Thermal and catalytic pyrolysis of plastic waste

2016

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Coking Reduction of Cr‐loaded Beta Zeolite during Polymer Cracking: Hydrocracking of Aromatics by Synergistic Effect of Cr⁶⁺ and Zeolitic Acid Sites

et al. 2023

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Zeolite deactivation induced by coke deposition is a critical problem in the industrialization of the chemical recycling (CR) of plastics. We previously demonstrated that Cr6+ species bonded to silanol groups in the zeolite framework inhibit coke deposition in low‐density polyethylene (LDPE) cracking. In this study, the role of Cr6+ species and the mechanism of coke reduction were determined experimentally. During LDPE cracking, hydrogen was generated from the alkane products at the Cr6+ sites. Furthermore, the hydrogenation and decomposition of aromatics, which are coke precursors, occurred at the zeolitic acid sites, resulting in the reduction of coke deposition. Owing to the synergistic effect of the Cr6+ and zeolitic acid sites, coke reduction was achieved without reducing cracking activity.

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Transformation of Single‐Use Plastics into Lighter Hydrocarbons via an Economical Coal Fly Ash based Zeolite Catalyst

Hossein Nazarloo,

Zabihi,

Shirvanimoghaddam

et al. 2023

ChemCatChem

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A mixture of zeolite X and A, derived from coal fly ash (CFA), was protonated and utilized as an acid catalyst to decompose single‐use plastics (SUP) waste into lighter hydrocarbons. Low‐density polyethylene (LDPE) was selected as the source of SUP, and this study aimed to investigate the catalytic effects of the protonated CFA‐derived zeolite (H‐XA) as an economical option on the LDPE pyrolysis temperature and output. CFA converted into H‐XA through the conventional alkali fusion, followed by sonication and simplified hydrothermal and protonation processes. The impact of the alkali agent ratio on the resulting product was investigated, and outcomes were evaluated. The product with optimum properties was then selected for investigation in the LDPE pyrolysis studies. Finally, the results were compared with commercial Protonated Zeolite Socony Mobil‐5 (H‐ZSM5) and thermal decomposition without catalysts. Regarding LDPE degradation temperature, H‐XA could lower that by 97 °C compared to thermal degradation, which was almost the same as commercial H‐ZSM5 with 110 °C. The pyrograms obtained through the Pyrolysis‐gas chromatography‐mass spectrometry (Py‐GCMS) analysis indicated the elimination of heavier hydrocarbons in the presence of H‐XA and the product spectra laid in the range of C3 to C9, which was entirely different from the LDPE with hydrocarbons of varying lengths. Moreover, kinetic studies on the LDPE decomposition reactions in this work have revealed that LDPE conversion occurs at a lower activation energy level in the presence of H‐XA, which is comparable to the energy level observed when H‐ZSM5 is used as the catalyst. The synthesis of H‐XA with desirable catalytic activity, such as the ability to lower the LDPE degradation temperature and make lighter hydrocarbons as the pyrolysis output, suggests the great potential of the CFA‐based acid catalyst for use in SUP recycling. This represent a game of waste versus waste within the framework of the circular economy, where the environment is the ultimate winner.

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The effect of ZSM-5 zeolite acidity on the catalytic degradation of high-density polyethylene using simultaneous DSC/TG analysis

Cited by 85 publications

References 36 publications

Thermal and catalytic pyrolysis of plastic waste

Thermal and catalytic pyrolysis of plastic waste

Coking Reduction of Cr‐loaded Beta Zeolite during Polymer Cracking: Hydrocracking of Aromatics by Synergistic Effect of Cr⁶⁺ and Zeolitic Acid Sites

Transformation of Single‐Use Plastics into Lighter Hydrocarbons via an Economical Coal Fly Ash based Zeolite Catalyst

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The effect of ZSM-5 zeolite acidity on the catalytic degradation of high-density polyethylene using simultaneous DSC/TG analysis

Cited by 85 publications

References 36 publications

Thermal and catalytic pyrolysis of plastic waste

Thermal and catalytic pyrolysis of plastic waste

Coking Reduction of Cr‐loaded Beta Zeolite during Polymer Cracking: Hydrocracking of Aromatics by Synergistic Effect of Cr6+ and Zeolitic Acid Sites

Transformation of Single‐Use Plastics into Lighter Hydrocarbons via an Economical Coal Fly Ash based Zeolite Catalyst

Contact Info

Product

Resources

About

Coking Reduction of Cr‐loaded Beta Zeolite during Polymer Cracking: Hydrocracking of Aromatics by Synergistic Effect of Cr⁶⁺ and Zeolitic Acid Sites