Development of sol-gel catalysts by use of fast combinatorial synthesis and high throughput testing techniques for catalytic oxidation of propylene to propylene oxide

Düzenli, Derya
Propylene oxide (PO) is an important raw material for the chemical industry, which is produced commercially by the chlorohydrin process and hydroperoxide process. However the deficiencies in these processes have given rise to considerable interest in the development of a direct route to PO that does not produce by-products or coproducts. The development of novel, active and selective catalysts for gas phase oxidation of propylene using molecular oxygen were studied via testing a large number of catalysts by high-throughput screening method over combinatorially prepared different catalytic system in this study. v The promoted and un-promoted silver (Ag), copper (Cu), manganese (Mn) mono and bimetallic catalytic system over high and low surface area silica, alumina, titanium oxide and titanium-silicate supports were prepared by single step sol-gel method and by incipient wetness method. The study to determine the most effective catalyst and promoter in the epoxidation reaction with different reaction conditions, showed that potassium (K)- promoted Cu metal supported over high surface area silica favored the PO production at a high reaction temperature (350 °C) and oxygen rich atmosphere (C3H6/O2=1.0). The catalyst showed high and low propylene oxide productivity was investigated by some of the characterization techniques. The highlydispersed copper particle over silica support was determined by XRD, TEM and XPS techniques. The only change between promoted and un-promoted catalyst was found out in the temperature dependence of propylene consumption and PO production rate. It was inferred that potassium (K) only neutralizes the acid sites of silica.


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Gezer, Miray; Önal, Işık; Department of Chemical Engineering (2014)
Propylene oxide is a significant intermediate chemical which has many derivatives used as raw materials in many industries such as automobile, cosmetic, medicine etc. However, its current production methods, chlorohydrin process and hydroperoxide process, are not preferred since they are economically and environmentally disadvantageous. Considering these negative effects, heterogeneous catalyst for direct propylene epoxidation is still being investigated. With an objective of filling this catalyst gap in th...
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A general synthetic strategy is developed to synthesize water soluble receptors by employing tripodal system based on a cyclotriphosphaze platform. The developed model is successfully synthesized and characterized by using elemental analysis, FT-IR, MALDI-TOF, H-1 NMR, C-13 NMR and P-31 NMR techniques. The fluorescence sensing performance of prepared water soluble tripodal systems were evaluated by UV/Vis and fluorescence spectroscopies. According to obtained results, two novel water-soluble sensing platfor...
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Erdoğdu, Anıl; Eroğlu, İnci; Department of Chemical Engineering (2004)
One of the most commonly used boron compounds, boric acid, is produced by dissolving colemanite (2CaO₉3B2O3₉5H2O) in aqueous sulfuric acid whereby gypsum (CaSO4₉2H2O) is formed as a byproduct and must be separated from the main product. This process consists of two steps, dissolution of colemanite and formation of gypsum. The amount of boric acid formed depends on the first step, dissolution of colemanite. In the latter step, gypsum crystals are formed and stay in the reaction mixture to grow up to a size l...
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ÖZÜN, Savaş; Atalay, M. Umit; Demirci, Şahinde (Informa UK Limited, 2019-05-19)
The long-chain alkyl amines and petroleum sulfonates are mostly used to remove unwanted minerals from feldspar ores in acidic pHs. In this study, their adsorption characteristics on pure albite and quartz were investigated by electrokinetic potential measurements, microflotation tests, Fourier transform infrared spectroscopy, and atomic force microscopy studies. According to the results, amine had strong influence on zeta potentials of both albite and quartz turning them positive and resulting over 90% flot...
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The supercritical fluid extraction (SFE) of aroma compounds from Thymbra spicata was studied. Response surface methodology (RSM) was used to optimize the parameters of the supercritical fluid extraction. Independent variables were temperature (40, 50 and 60 degreesC), pressure (80, 100 and 120 bar) and time (30, 60 and 90 min). Dependent variables were yield, monoterpene, sesquiterpene and oxygenated monoterpene contents.
Citation Formats
D. Düzenli, “Development of sol-gel catalysts by use of fast combinatorial synthesis and high throughput testing techniques for catalytic oxidation of propylene to propylene oxide,” Ph.D. - Doctoral Program, Middle East Technical University, 2010.