Dealumination of ZSM-5 zeolites by steaming.

Adsorption of carbon monoxide in H-ZSM-5 and Li-ZSM-5 zeolites: an embedded ab initio cluster study

The absorption of carbon monoxide with H-ZSM-5 and metal-substituted Li-ZSM-5 zeolites has been investigated by Ž . using both cluster and embedded cluster approaches at the HFr6–31G d,p level of theory. For the H-ZSM-5 zeolite, the binding energy of CO on a 3T quantum cluster is predicted to be 2.25 kcalrmol for the C-bound complex. The O-bound complex was found to be less stable by about 0.84...

ZnO modified ZSM-5 and Y zeolites fabricated by atomic layer deposition for propane conversion.

ZnO modified ZSM-5 and Y zeolites are synthesized by performing atomic layer deposition (ALD) of ZnO to HZSM-5 and HY using diethyl zinc and water as the precursors. The surface area and pore volume of ZSM-5 and Y zeolites are progressively reduced with the increasing number of ZnO ALD cycles. XRD and SEM characterization methods show that highly dispersed ZnO species are deposited on the inter...

Effect of Steam Deactivation Severity of ZSM-5 Additives on LPG Olefins Production in the FCC Process.

ZSM-5-containing catalytic additives are widely used in oil refineries to boost light olefin production and improve gasoline octanes in the Fluid Catalytic Cracking (FCC) process. Under the hydrothermal conditions present in the FCC regenerator (typically >700 °C and >8% steam), FCC catalysts and additives are subject to deactivation. Zeolites (e.g., Rare Earth USY in the base catalyst and ZSM-...

Tailoring ZSM-5 Zeolites for the Fast Pyrolysis of Biomass to Aromatic Hydrocarbons.

The production of aromatic hydrocarbons from cellulose by zeolite-catalyzed fast pyrolysis involves a complex reaction network sensitive to the zeolite structure, crystallinity, elemental composition, porosity, and acidity. The interplay of these parameters under the reaction conditions represents a major roadblock that has hampered significant improvement in catalyst design for over a decade. ...

Crystallization of Sub-Micrometer Sized ZSM-5 Zeolites in SDA-Free Systems