Aluminium chloride: A new aluminium source to prepare SAPO-34 catalysts with enhanced stability in the MTO process

The MTO process produces lower olefins from natural gas or coal via methanol, providing an interesting route to obtain valuable petrochemicals from carbon sources alternative to petroleum. Small-pore silicoaluminophosphate SAPO-34 has been proven an efficient catalyst for the MTO process, showing exceptionally high selectivity to lower olefins. However, these catalysts undergo rapid deactivation due to deposition of high molecular weight hydrocarbons on the pore entrances, which completely blocks the internal channels of the SAPO-34 crystals. In the present work, we explore the use of very dilute zeotype precursor solutions to reduce the size of the crystals of these materials, improving greatly their catalytic behaviour in the MTO process by increasing the catalyst life time. (C) 2013 Elsevier B.V. All rights reserved.