Catalytic reaction of propylene to propylene oxide on various catalysts

Kalyoncu, Şule
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 catalytic performances of these catalyst candidates were investigated. The study showed that commercial silica (c-SiO2) is the most effective support when compared to silica (SiO2) and silica synthesized with templete (t-SiO2). Among bimetallic catalytic systems containing Ag, Ru, Mn and Cu metals, c-SiO2 supported Cu-Ru catalyst was determined as the most active catalytic system. In addition, the most effective v catalyst and promoter in the epoxidation reaction was determined as NaCI promoted Cu-Ru catalyst supported over c-SiO2 with 35.98% selectivity& 9.55% conversion (3.44% yield) at 3000C and 0.5 feed gas ratio (C3H6/O2).. In the study, the selected catalysts showed low and high PO productivity were also investigated by characterization techniques such as XRD, XPS, BET and FTIR.It was inferred from characterization tests that bimetallic systems reveal a synergistic behavior by exposing more active sites on the silica support material with respect to their monometallic counterparts. Besides, NaCl catalytic promoter has a strong interaction particularly with the Cu sites on the Cu/Ru/SiO2 catalyst surface, altering the electronic structure of Cu sites that favors to PO production.


Epoxidation of Propene by High-Throughput Screening Method Over Combinatorially Prepared Cu Catalysts Supported on High and Low Surface Area Silica
Duzenli, Derya; ŞEKER, EROL; Senkan, Selim; Önal, Işık (2012-10-01)
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 o...
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...
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Citation Formats
Ş. Kalyoncu, “Catalytic reaction of propylene to propylene oxide on various catalysts,” M.S. - Master of Science, Middle East Technical University, 2012.