The catalytic performance of Fe-Cr/ZrO2 catalysts, prepared by two different methodsscoprecipitation and coprecipitation-impregnation were examined in oxidative dehydrogenation of ethane to ethylene using CO2 as an oxidant. Thermogravimetric analysis and physicochemical characterization such as XPS, XRD, and BET were performed to explore the correlation of catalytic performance with physicochem...

Title of thesis: ANALYSIS OF RHEOLOGICAL PROPERTIES AND MOLECULAR WEIGHT DISTRIBUTIONS IN CONTINUOUS POLYMERIZATION REACTORS Kedar Himanshu Dave, Master of Science, 2004 Thesis directed by: Professor Kyu Yong Choi Department of Chemical Engineering This work explores the possibility of exploiting structure-property relationships to manufacture tailor-made polymers with target end-use properties...

The metal-catalyzed polymerization of simple olefins, such as ethylene and propylene, has been one of the transformational discoveries in chemistry of the 20th century. It is difficult to imagine today’s civilization without ubiquitous plastics, such as polyethylene and related polymers. Although often attributed to Karl Ziegler and Giulio Natta, the winners of the 1963 Nobel Prize in Chemistry...

In this present study, the catalytic dehydration of ethanol over three different Al-based solid acid catalysts including H-beta zeolite (HBZ), modified H-beta zeolite with γ-Al2O3 (Al-HBZ) and mixed γχ phase of Al2O3 (M-Al) catalysts was investigated. The ethanol dehydration reaction was performed at temperature range of 200 to 400oC. It revealed that all catalysts exhibited higher ethanol conv...

Free radical polymerization of ethylene in an intermediate pressure and temperature range (P(ethylene) < 250 bar and 50 °C < T < 90 °C) in the presence of an organic solvent has been studied. Under selected conditions (P, T) and according to the amount of organic solvent added, either a supercritical monophasic or a biphasic medium is obtained. In the case of a biphasic medium, polymerization o...

In propylene (C3) polymerization with Ziegler-Natta catalyst, not only internal donor but also external is very important to make isotactic polypropylene (PP) higher yield. Most propylene-based polymers have been commercially produced catalysts combined dialkyl-dialkoxy silane compounds (R2Si(OR)2) such as C-donor, P-donor, and D-donor donors. this paper, we will introduce the performance amino...

Quantitative structure–thermostability relationship was carried out for four series of bis(imino)pyridine iron (cobalt) complexes and α-diimine nickel complexes systems in ethylene oligo/polymerization. Three structural parameters were correlated with thermal stability, including bond order of metal-nitrogen (B), minimum distance (D) between central metal and ortho-carbon atoms on the aryl moie...

We treated silica with tris(pentafluorophenyl)borane, B(C6F5)3, to create borane-functionalized support, SiO2–B(C6F5)3 which was then used as a support and co-catalyst for the in situ activated dichloro-zirconocene (Cp2ZrCl2/TIBA) and dimethyl-zirconocene catalyst systems (Cp2Zr(CH3)2) for ethylene polymerization. The surface modifications of SiO2– B(C6F5)3 was investigated by SEM–EDX, FTIR and...