Sulfonic functionalized SBA-15 catalysts in the gas phase glycerol dehydration. Thermal stability and catalyst deactivation

C. LAGO; M.S. LEGNOVERDE; C.A. QUERINI; B.O. DALLA COSTA; H.P. DECOLLATI

MICROPOROUS AND MESOPOROUS MATERIALS

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 2016 vol. 230 p. 66 - 75

1387-1811

The catalytic conversion of glycerol to acrolein was studied using sulfonicfunctionalized mesoporous silica SBA-15. The catalysts were prepared by the cocondensationmethod, conducting the silica synthesis and functionalization of its surfacewith thiol-propyl groups in the same stage. In a next step, the oxidation of thiol groups to sulfonic groups was made varying the concentration of H2O2 in order to obtain catalysts with different levels of acidity on the surface. The solids were characterized by BET, SEM, FTIR, XPS, and potentiometric titration with n-butilamine. The thermal stability was analyzed by thermogravimetry (TGA) and temperature-programmed desorption (TPD). The reaction tests were performed at different temperatures between 275 ºC and 350 ºC, and under feed flow conditions that allowed the study of the deactivation phenomena by coke deposition. The best temperature in order to maximize the acrolein yield was 300 ºC. Higher temperatures led to a rapid deactivation by acombined effect of coke deposition and decomposition of functional groups.