Functionalization of MCM-22 by Dual Acidic Ionic Liquid and Its Paraffin Absorption Modulation Properties

Abstract

A dual acidic ionic liquid 3-sulfobutyl-1-(3-propyltriethoxysilane)imidazolium hydrogen sulfate was synthesized and immobilized on MCM-22 via covalent bonding, which was characterized by FT-IR, TGA, SEM, BET, XPS, and XRD. The modulating of adsorption capacity by novel immobilized ionic liquid was demonstrated by ethane and ethylene. The results indicate that after immobilization, the main structure of the MCM-22 remains unchanged and the acid amount increased. This material displays relatively superior adsorption ability in tuning the ratio of paraffin/olefin (the adsorbed ratio of ethane/ethylene increased over 30%). The immobilized ionic liquid is believed to tune the adsorption capacity resulting in these enhanced results. In addition, this concept could also be applicable to Friedel–Crafts alkylation, catalytic cracking reaction, adsorption separation, or other competitive adsorption reactions.