Papers by Keyword: Propylene

Abstract: The GdVO₃ and GdVO₄ catalyst has been prepared via solid-phase synthesis. It has been shown by a complex of physical and chemical methods that or GdVO₃, the main one is the phase with the structure of the first homologue of the Roldlesden-Popper series of a rhombical distorted perovskite. Orthovanadate of GdVO₄ crystallize in the structural type of zircon. The catalytic properties of GdVO₃ and GdVO₄ are studied in the propane cracking process to form propylene and ethylene. It was found that GdVO₃ and GdVO₄ has a high selectivity and catalytic properties. It was shown that propane conversion started at 773 K, was only 2% at 873 K, and raising the temperature to 923 K increased propane conversion to 21%. In the presence of GdVO₄ and GdVO₃, a considerable increase in propane conversion was observed that reached 60% at 923 K. The structure of the catalyst is stable under the conditions of preferential C₃H₈ reduction. Deactivation was much faster with GdVO₃, and it was observed after 20 h of operation at a rate that was slightly slower than the one for GdVO₄.

Abstract: An influence of support acidity on the dimerization function on Pd-containing catalysts was studied. After addition of Re₂O₇ to PdO/SZ as ethylene dimerization catalyst with high butene-2 selectivity the obtained PdO-Re₂O₇/SZ catalyst was tested in direct synthesis of propylene from ethylene under mild conditions (40°C and atmospheric pressure). Propylene yield was approximately 45%, which is close to equilibrium one.

Abstract: This article evaluate the recycling of renewable fiber feasibility from the economic cost, the key factor is the treatment methods, reuse direction, and its economic costs. Textile fiber material recycling economic cost, mainly through analysis the cost of new textile fiber materials prices and the price of recycled fiber, of which the price of recycled fiber is the recovery of the prices of textile fibers combined with the recycling processing costs.

Abstract: Polypropylene that consist of different loading of rice bran (RB) (0wt%, 10wt%, 20wt%, 30wt%, 40wt%) and sepiolite (SEP) (0phr, 1phr, 2phr, 3phr, 4phr, 5phr) were prepared by twin-screw extruder followed by compression moulding. The effect of RB and SEP loading on the thermal properties and flammability properties were studied through thermal gravimetric analysis (TGA) and UL94 horizontal burning test (UL94HB) respectively. The result from TGA revealed that RB content at 40%wt and SEP content at 4phr showed good thermal stability. The sepiolite used for flammability properties had improved the flammability matrix; however, the amount of SEP use in this study is not enough to improve the flammability of PP/RB composite.

Abstract: Since the order of activity of α, β, γ - bismuth molybdates has been debated in the literature, this article aims to clarify this by testing catalytic activity of three phases prepared by different methods, calcined at different temperatures. The impurity by other phases is one reason differentiate catalytic activity of these catalysts. It can be said that the order of three pure phases is: β slightly > α > γ.Keywords: bismuth molybdates, propylene, catalysts, selective oxidation

Abstract: To establish a new production route of biomass-derived BTX and propylene, the catalytic conversion of oxygen-containing intermediates which are furfural, levulinic acid, acetic acid or butyric acid, obtained by hydrothermal reactions of bagasse or fermentation of molasses was investigated with zeolites, ZSM-5, SAPO-11 and SAPO-34. Levulinic acid and acetic acid were suitable for generating BTX with ZSM-5. On the other hand, the butyric acid was valuable for converting to chemical raw materials with ZSM-5. By using SAPO-11 as the catalyst, butyric acid converted to propylene at high yields. The yield for propylene was the maximum value 58.8C% at 723K, especially the ratio of propylene to gaseous hydrocarbon products increased up to 90.4C%.

Abstract: Ethanol has great potential to be a candidate for the source of light olefins such as ethylene and propylene. However, ethanol to olefin (ETO) process has not been fully investigated. In this work, the conversion reactions of ethanol were carried out at 673 K under atmospheric pressure on SAPO-34 and SAPO-34/SiO₂ catalysts. SAPO-34 and SAPO-34/SiO₂ exhibit higher selectivity for propylene than H-ZSM-5 zeolite catalysts do. The SAPO-34 with silica binder showed better catalytic performance for the transformation of ethanol to propylene than the SAPO-34 catalyst.

Abstract: Ethanol has great potential to be a candidate for the source of light olefins such as ethylene and propylene. However, ethanol to olefin (ETO) process has not been fully investigated. In this work, the conversion of ethanol to propylene was investigated over H-ZSM-5 zeolite catalysts with different Si/Al₂ ratios (80 and 280). Similar product distributions were obtained with the two catalysts at different contact times, and the turnover frequencies of the two catalysts were identical. These results strongly imply that the product distribution was independent of the Si/Al₂ ratio and that the active site for conversion of ethanol to propylene was the identical for both catalysts.

Abstract: Superfine HZSM-5 zeolites were synthesized by different methods, and their catalytic performance for the coupling conversion of methanol and 1-butylene to propylene was investigated. In addition, these catalysts were characterized by XRD, SEM, N₂ isothermal adsorption-desorption, and NH₃-TPD. Z5-A catalyst showed the highest reactivity among these catalysts and could keep good stability, due to its superfine particle size, large surface area and proper acidity.

Abstract: Coke on Zn/Hβ catalyst in ethanol to propylene was studied in continuous-flow fixed-bed reactor. The physicochemical properties of these fresh and used catalysts were characterized by NH₃-TPD, N₂ isothermal adsorption-desorption and TPO. These results showed that the medium and strong acid sites might be responsible for the production of coke and coke mainly deposited on external surface and microporous mouth. In addition, the coke might be consisted of soft coke and hard coke.