Alternative acid catalysts for the stable and selective direct conversion of CO2/CO mixtures into light olefins

Different acid catalysts (silicoaluminophosphates (SAPOs) -34, −18, and − 11, HZSM-5 zeolite) were tested as components of In2O3-ZrO2/acid tandem in the direct synthesis light olefins by hydrogenation CO2, CO their mixture. The conversion yield selectivity evidence that presence large amount strongly acidic sites SAPO-34 favors extent reaction mechanism with methanol intermediate, minimizing secondary methanation reactions. In addition, shape boosts (mainly propylene), limiting reactions for formation other hydrocarbons. Using SAPOs enhances when co-feeding CO2 CO. Despite all undergo deactivation coke deposition (mostly catalyst), a pseudo-steady state stable remaining activity is acquired. From study nature, soft hard discerned. For complete regeneration catalyst, stripping not sufficient combustion at 500 °C (little developed) deposited on micropores required.