Abstract

The microporosity of H-MCM-22 samples, fresh and deactivated by coke during methylcyclohexane transformation at 350 °C for 10 h, was characterised by adsorption of nitrogen and organic molecules of different size, namely, p- and o-xylenes, mesitylene and methylcyclohexane. Nitrogen adsorption was also carried out on the fresh sample after pre-adsorption of the hydrocarbons. All of these can fit the outer 12 MR cups, but show differences in their ability to enter the internal microporosity. p-Xylene can enter all the inner micropores, methylcyclohexane adsorbs in the supercages and at some sinusoidal channel entrances, o-xylene is adsorbed at the pore windows of the supercages only, and mesitylene is completely excluded from the inner micropores. It was deduced that the microporosity of the MCM-22 sample investigated consists of 0.01 cm 3 g −1 of outer pockets (∼5% of the total volume), 0.06 cm 3 g −1 of sinusoidal channels (∼32%) and 0.12 cm 3 g −1 of supercages (∼63%). Coke deposited during methylcyclohexane transformation caused the complete blockage of the supercages but had no effect on the outer cups and sinusoidal channels.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.