Epoxidation of Propene by High-Throughput Screening Method Over Combinatorially Prepared Cu Catalysts Supported on High and Low Surface Area Silica

Duzenli, Derya
Senkan, Selim
Önal, Işık
Gas phase epoxidation of propene using molecular oxygen was studied by use of a high-throughput testing technique. A large number of catalysts including promoted and un-promoted Cu were synthesized in a much faster combinatorial fashion using a sol-gel method. Metal catalysts supported on high and low surface area silica were tested and ranked in a high-throughput activity and selectivity testing apparatus at different experimental conditions such as reaction temperature and reactant gas ratio. The amount of Cu loading and the addition of alkali promoters such as K and Li resulted in different tendencies in consumption rate for both silica materials. The maximum PO production rate was obtained as 25.82 mu mol/g/cat./min (2.90 % conv. and 20.49 % selectivity) for 3 % Cu-2.25 % K catalyst supported on high surface area silica. There was no noticeable difference in structural and chemical properties of catalysts after modification with K when examined by XRD and TEM; however, the overall activation energy of un-modified catalysts (92 kJ/mol) decreased to 71 kJ/mol for K-modified catalyst. There was negligible difference between the activation energies calculated for PO production (75 vs. 77 kJ/mol).


Propylene Epoxidation: High-Throughput Screening of Supported Metal Catalysts Combinatorially Prepared by Rapid Sol-Gel Method
Önal, Işık; Seubsai, Anusorn; Kahn, Michael; ŞEKER, EROL; Senkan, Selim (2010-02-01)
The gas phase oxidation of propylene using molecular oxygen was studied on a variety of supported metal catalysts. The most promising PO activity was obtained for Cu supported on high surface area SiO(2) and the multimetallic systems exhibit synergistic effects that increased the desired PO yield by several folds for Ag promoted with Cu on SiO(2) after screening a large number of catalysts by a high throughput testing technique.
Direct epoxidation of propylene to propylene oxide on various catalytic systems: A combinatorial micro-reactor study
Kalyoncu, Sule; Duzenli, Derya; Önal, Işık; Seubsai, Anusorn; Noon, Daniel; Senkan, Selim (2015-02-10)
A combinatorial approach is used to investigate several bimetallic catalytic systems and the promoter effect on these catalysts to develop highly active and selective catalysts for direct epoxidation of propylene to propylene oxide (PO) using molecular oxygen. 2%Cu/5%Ru/c-SiO2 catalyst yielded the highest performance with high propylene conversion and PO selectivity among the bimetallic catalytic systems including silver, ruthenium, manganese and copper metals. On the other hand, the most effective catalyst...
Catalytic reaction of propylene to propylene oxide on various catalysts
Kalyoncu, Şule; Önal, Işık; Şeker, Erol; Department of Chemical Engineering (2012)
Throughout this thesis work, various catalysts were investigated with combinational approach to develop highly active and selective novel catalysts for direct epoxidation of propylene to PO using molecular oxygen. The promoted and un-promoted silver (Ag), copper (Cu), ruthenium (Ru), manganese (Mn) mono and multimetallic catalytic systems over different silica supports were prepared via sol-gel method and incipient wetness method. In addition to support effect, the effects of different promoters on the cata...
Epoxidation reactions of small alkenes on catalytic surfaces
Kurnaz, Emine; Önal, Işık; Department of Chemical Engineering (2011)
Propylene epoxidation reaction was investigated on catalytic surfaces of chlorinated copper(I) oxide and ruthenium(IV) oxide using periodic density functional theory (DFT). Cu2O(001) and (110) surface of RuO2 was selected to generate chlorinated surfaces to be used in the study. Besides epoxidation, other reactions that compete with epoxidation were also studied such as formations of allyl-radical, acrolein, acetone on chlorinated Cu2O(001) and formations of propionaldehyde, allyl-radical and acetone on chl...
Adsorption calorimetry in supported catalyst characterization: Adsorption structure sensitivity on Pt/-gamma-Al2O3
Üner, Deniz (Elsevier BV, 2005-08-15)
In this study, the structure sensitivity of hydrogen, oxygen and carbon monoxide adsorption was investigated by changing the metal particle size of Pt/Al2O3 catalysts. The 2% Pt/Al2O3 catalysts were prepared by incipient wetness method; the particle size of the catalysts was modified by calcining at different temperatures. The differential heats of adsorption of hydrogen, carbon monoxide and oxygen were measured using a SETARAM C80 Tian-Calvet calorimeter. Hydrogen chemisorption sites with low and intermedi...
Citation Formats
D. Duzenli, E. ŞEKER, S. Senkan, and I. Önal, “Epoxidation of Propene by High-Throughput Screening Method Over Combinatorially Prepared Cu Catalysts Supported on High and Low Surface Area Silica,” CATALYSIS LETTERS, pp. 1234–1243, 2012, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/30638.