Dimethylether (DME) can be used for energy purpose instead of GLP and diesel, or as a feedstock for
fuel cells. Moreover, DME is a platform and is an attractive alternative as a clean propellant.
At the moment, DME is produced by methanol dehydration. This methanol could be obtained from
syngas produced by biomass gasification, generating a sustainable source for DME synthesis. For this
reason, DME is being deeply studied as a potential renewable substitute for petroleum derivative. Lots
of papers search for the best operating conditions of many catalysts for the production of DME, however,
addressing how the catalyst deactivates, mainly by coke deposition, is also an issue of great interest for
this process.
Our work focuses on this point, given that the knowledge of deactivation details will allow us optimizing
the catalyst synthesis for the best DME production process conditions. Physical (CO2 gasification) and
chemical (phosphoric acid) activation of an agroindustrial waste (olive stone) have been used to
prepared activated carbons that have been studied as catalyst supports for the methanol to DME
reaction. These porous carbons were impregnated with zirconium to obtain the final carbon catalysts.
Thus, porous carbons containing different surface catalyst phases (C, C-P, C-Zr and C-P-Zr) were
prepared. The methanol to DME reaction experiments were carried out in a laboratory fixed bed reactor
at a partial pressure of 0.04 atm and at several residence times (from 0.05 to 0.1 g·s/μm) and
temperatures (from 300 to 600ºC).
The catalytic system containing surface C-P-Zr seems to present two kinds of active sites, which are
deactivated at different rates. One of them loses their activity fast (even at the lowest temperature
studied), while the other one does not lose activity at the studied temperatures, starting to deactivate only
at temperatures above 400ºC.