Effect of promoters on the structures and properties of the RuB-γ-Al2O3 catalyst.pdf

Journal of Molecular Catalysis A: Chemical 230 (2005) 69–77 Effect of promoters on the structures and properties of the RuB/
-Al2O3 catalyst Ge Luo, Shirun Yan ? , Minghua Qiao, Kangnian Fan ? Department of Chemistry and Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Fudan University, 220 Handan Road, Shanghai 200433, PR China Received 25 August 2004; received in revised form 17 December 2004; accepted 17 December 2004 Available online 19 January 2005 Abstract Effect of promoters (Co, Fe, Sn, Zn) on structures, properties and catalytic performance of RuB/
-Al2O3 catalyst was studied using in situ XRD, TEM, H2-TPD, XPS and liquid-phase hydrogenation of ethyl lactate to 1,2-propanediol (PDO). It was found that incorporation of Sn or Fe improved the dispersion and thermal stability of RuB. The electron density of Ru and the strength and capacity of H2 adsorption on the R c l T ? K 1 u c p v c p a e s c p c C k 1 duB catalyst were also enhanced by the incorporation of Sn or Fe. The incorporation of Co or Zn led to a significant decrease in H2 adsorption apacity of the RuB catalyst. Both ethyl lactate conversion and selectivity to 1,2-PDO increased with the incorporation of Sn or Fe. The ethyl actate conversion decreased sharply with the incorporation of Zn or Co accompanied by an increase in selectivity to 1,2-PDO and lactic acid. he effect of promoters on reaction behavior was discussed on the basis of the characterizations. 2004 Elsevier B.V. All rights reserved. eywords: RuB/
-Al2O3 catalyst; Promoting effect; Structures; Ethyl lactate hydrogenation . Introduction 1,2-Propanediol (PDO), a material that has been widely sed in pharmaceutical and chemical industries is commer- ially produced by the hydration of propylene oxide that is roduced via the oxidation of propylene. This process in- olves either hydroperoxidation chemistry or the antiquated hlorhydrin process [1]. Development of alternative green rocesses for the synthesis of 1,2-PDO ha