Continuous gas-phase desulfurisation using supported ionic liquid phase (SILP) materials

Abstract

Supported ionic liquid phase (SILP) materials have been developed for a continuous gas cleaning process. The technology is exemplified for the desulfurisation of a model gas stream consisting of 500 ppm_wt n-butyl mercaptan in n-heptane vapour to levels of mercaptan below 5 ppm_wt. By varying the ionic liquid structure, acidity and loading, [C₁₂MIM]Cl/SnCl₂ (X_SnCl2 = 0.50) on alumina in an ionic liquid loading of 20 vol% of the support's pore volume was identified as a particularly suitable gas sorption system. Breakthrough experiments demonstrate desulfurisation performance of up to 130 h time-on-stream, and the suitability of the system for loading/unloading cycles in a pressure and temperature swing operation mode.