Journal ArticleDOI
Insights into the coke deposited on HZSM-5, Hβ and HY zeolites during the cracking of polyethylene
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TLDR
In this article, the effect of the zeolite structure (HZSM-5, Hβ and HY) on coke deposition during the cracking of high-density polyethylene has been studied by combining the results of multiple spectroscopic and analytical techniques: FTIR, Raman, UV-vis, 13 C NMR and coke extraction.Abstract:
The effect of the zeolite structure (HZSM-5, Hβ and HY) on coke deposition during the cracking of high-density polyethylene has been studied by combining the results of multiple spectroscopic and analytical techniques: FTIR, Raman, UV–vis, 13 C NMR and coke extraction, followed by GC-MS and 1 H NMR analysis. In addition, by combining FTIR and temperature programmed oxidation (TPO) analysis we obtained information on the coke: properties, burn-off, and changes in composition during catalyst regeneration. Samples of the spent catalysts were obtained in a state-of-the-art pilot plant (conical spouted bed reactor) after the continuous treatment of 900 g (1 g min −1 , 15 h) of high-density polyethylene at 500 °C, using 30 g of catalyst. The results show that as the pore diameter of the zeolite is increased, bimolecular reactions (hydrogen transfer and oligomerizations), condensations and cyclizations are enhanced, yielding more aromatic coke. Furthermore, the pore topology of the HZSM-5 zeolite improves the flow of coke precursors (also favored by the high flow rate of N 2 ) to the outside of the catalyst; viz. HZSM-5 catalyst preserves its activity for longer.read more
Citations
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Assessment of acidity and the zeolite porous structure on hydrocracking of HDPE
TL;DR: In this paper , the authors present a rationale for catalytic activity and product distribution in HDPE hydrocracking promoted by zeolite catalysts, and assess the catalyst stability.
Journal ArticleDOI
Performance and coke species of HZSM-5 in the isomerization of styrene oxide to phenylacetaldehyde
TL;DR: In this paper, the performance and coke species of HZSM-5 in the isomerization of styrene oxide to phenylacetaldehyde was investigated under gas phase, free of solvents.
Journal ArticleDOI
Direct Synthesis of Ethylene and Hydrogen from CO2 and Ethane over a Bifunctional Structured CaO/Cr2O3-V2O5/ZSM-5 Adsorbent/Catalyst Monolith
Journal ArticleDOI
Towards continuous deoxygenation of acetic acid catalyzed by recyclable mono/bi/trimetallic zeolite catalysts
TL;DR: In this article, a series of mono (Ni, Cu, Co), bi (NiCu, NiCo, CuCo), and trimetallic mordenite supported catalysts were characterized and evaluated for the continuous, near-atmospheric pressure, thermal deoxygenation of acetic acid.
Journal ArticleDOI
Fluoride-treated IM-5 zeolite as a highly active catalyst for the production of jet fuels by the oligomerization of 1-hexene
TL;DR: In this article , an efficient and selective IM-5 zeolite-derived catalytic system has been developed for the oligomerization of 1-hexene, which targets high-concentration of jet-range hydrocarbons.
References
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