Impact of Lewis Acid Sites on the Catalyst Lifetime for Methanol‐to‐Hydrocarbons over Mg‐Dealuminated BEA Zeolite

In the present work, we show the effect of magnesium incorporation during the methanol‐to‐hydrocarbon reaction on partial dealuminated beta zeolite. Based on our findings, we observed an increase in the catalyst lifetime with the increase in Mg concentration, as a consequence of the rise in the Lewis acid site population. However, Mg concentrations higher than 1.5 wt% provokes the formation of MgO aggregates, promoting a faster catalyst deactivation. The formation of Lewis acid sites by Mg incorporation limits hydrogen transfer reaction, resulting in a lower selectivity of paraffin and aromatics. Operando UV‐vis results show that the hydrocarbon species present a similar nature, independent of the Brønsted acid site number, while the concentration differs. Depth analysis of the operando spectroscopy data shows a decrease in the formation rate of polyaromatic species with the Mg incorporation, which correlates with lifetime extension.