Selective Hydrodeoxygenation of m-Cresol over Bifunctional Metal-Acid Catalysts

2012 Spring Symposium

Andrew Fos­ter, Phuong Do, Jing­guang Chen and Raul F. Lobo
Depart­ment of Chem­i­cal and Bio­mol­e­c­u­lar Engi­neer­ing
Uni­ver­si­ty of Delaware

Abstract — Upgrad­ing of bio­mass derived pyrol­y­sis oil is nec­es­sary to pro­duce liq­uid fuels that can seam­less­ly be inte­grat­ed with the cur­rent trans­porta­tion fuel infra­struc­ture and hydrodeoxy­gena­tion (HDO) is one of the most effec­tive meth­ods to accom­plish this task. In this talk we will describe the HDO of m-cresol (3-methylphe­nol) inves­ti­gate as a mod­el reac­tion for the HDO of the phe­no­lic frac­tion of pyrol­y­sis oil of lig­no­cel­lu­losic bio­mass. To facil­i­tate selec­tive removal of oxy­gen with­out fur­ther hydro­gena­tion of unsat­u­rat­ed C-C bonds, exper­i­ments were con­duct­ed at low hydro­gen pres­sures. Kinet­ic stud­ies in a plug-flow reac­tor show that toluene can be selec­tive­ly pro­duced from m-cresol over a Pt/γ-Al2O3 cat­a­lyst at pres­sures as low as 0.5 atm H2 and 533 K. A reac­tion net­work has been devel­oped based on inves­ti­ga­tion of the reac­tions of m-cresol, and the observed reac­tion prod­ucts and inter­me­di­ates over Pt/γ-Al2O3 and oth­er sup­ports. m-Cresol HDO pro­ceeds by a bifunc­tion­al mech­a­nism, requir­ing met­al-cat­alyzed hydro­gena­tion of the aro­mat­ic ring fol­lowed by acid-cat­alyzed dehy­dra­tion. The degree of hydro­gena­tion of the pool of inter­me­di­ates pri­or to dehy­dra­tion large­ly deter­mines the resul­tant prod­uct dis­tri­b­u­tion. The effect of the addi­tion of a sec­ond met­al (Ni and Co) on cat­a­lysts activ­i­ty is also inves­ti­gat­ed. It is shown that selec­tive pro­duc­tion of toluene requires the dehy­dra­tion to occur before sat­u­ra­tion of the aro­mat­ic ring.

Speak­er Biog­ra­phy — Raul F. Lobo is pro­fes­sor of Chem­i­cal Engi­neer­ing at the Uni­ver­si­ty of Delaware and Direc­tor of the Cen­ter for Cat­alyt­ic Sci­ence and Tech­nol­o­gy. His research inter­ests span the devel­op­ment of nov­el porous mate­ri­als for catal­y­sis and sep­a­ra­tions, the chem­istry of zeo­lites at high tem­per­a­tures, the devel­op­ment of nov­el pho­to­cat­a­lysts and the sci­en­tif­ic aspects of cat­a­lyst syn­the­sis. He has pub­lished over one hun­dred ref­er­eed reports and he is co-inven­tor in three US patents. He obtained his under­grad­u­ate degree in Chem­i­cal Engi­neer­ing at the Uni­ver­si­ty of Cos­ta Rica and lat­er moved to Cal­i­for­nia to pur­sue grad­u­ate stud­ies in Chem­i­cal Engi­neer­ing at Cal­tech. He worked for one year at Los Alam­os Nation­al Lab­o­ra­to­ry, New Mex­i­co as a post­doc­tor­al fel­low and start­ed his aca­d­e­m­ic career at the Cen­ter for Cat­alyt­ic Sci­ence and Tech­nol­o­gy, Depart­ment of Chem­i­cal Engi­neer­ing, Uni­ver­si­ty of Delaware in 1995.