Interactions between methanol and active sites in CHA-type zeolite catalysts

The increasing demand for fuel and bulk chemicals across the globe and the need to reduce carbon emissions has prompted significant research into more sustainable, and economical, feedstocks to crude oil such as biomass and syngas derived methanol both of which could be used in methanol-to-hydrocarbons (MTH) processes.
CHA-type zeolites, specifically H-SAPO-34, have shown promise for use in the methanol-to-olefins (MTO) reaction and will play a key role in future fuel and chemicals production. The aim of this work is to use INS to probe the interactions between methanol and the Brønsted acid active sites within different CHA-type zeolite catalysts, namely SSZ-13 and H-SAPO-34 both used by industry. Both catalysts will be studied with varying framework composition. The varying Si/Al ratio (dictating the concentration of Bronsted acidic active sites) will allow for the effect of increased acidic site density to be probed. The detailed understanding of methanol behaviour in this key step of the MTO reaction in CHA-type zeolite catalysts will be of crucial importance to the design and optimisation of future MTO catalysts.