Styrene oxidation

Hydrophilic nano MnO is shown to have significant stability in aqueous media for oxidation of styrene. Different catalysts have been used to synthesis styrene oxide, but MnO-CaL is considered the efficient and selective catalyst to produce styrene oxide. In general, this paper reported especial strategy for synthesis of novel nano MnO that stabilized with oleic acid in chloroform and changing nature of its stabilizer by exchanging oleic acid with lignosulfunate and displays its catalytic activity towards selective oxidation of styrene.

13p langthannam 29-12-2021 11 0   Download

Blends of polyphenylene oxide (PPO) and acrylonitrile butadiene styrene (ABS) were prepared by melt-mixing method. Flammability of these blends was studied by using UL-94 (plastics flammability standard) and LOI (limited oxygen index) tests. The results showed the role of PPO as flame retardant in the blends which can inhibit the burning process. All blends of PPO and ABS were graded as V-1 and LOI values were higher than 21. As a physical mixture, tensile strength of PPO/ABS blends maintained values between the tensile of neat ABS and PPO.

4p cothumenhmong11 06-05-2021 22 0   Download

In this work, silver nanocatalyst loaded on vanadium phosphorus oxide (Ag/VPO) for oxidation of styrene to benzaldehyde was synthesized by method including impregnating of VPO substrate with colloid solution of Ag nanoparticles (NPs). VPO substrate was prepared by microwave-assisted reaction of vanadium and phosphorus precursors. Meanwhile, Ag/PVP NPs with the size of 7.5 nm and spherical shape, determined by transmission electron microscopy (TEM), were prepared in solution using NaBH4 as reducing agent and polyvinylpyrrolidone (PVP) as protecting agent.

9p cothumenhmong9 04-01-2021 12 0   Download

In the oxidative dehydrogenation (ODH) process that converts ethylbenzene to styrene, vanadium-based catalysts, especially V2O5, are used in a CO2 atmosphere to enhance process efficiency. Here we demonstrate that the activation energy of V2O5 can be manipulated by exposure to high pressure CO2, using V2O5 nanowires (VON). The oxidation of V4+ to V5+ was observed by X-ray photoelectron spectroscopy. The ratio of V4+/ V5+ which the typical comparable feature decreased 73.42%. We also found an increase in the interlayer distance in VON from 9.95 Å to 10.10 Å using X-ray diffraction patterns.

5p partimesinhvien 08-05-2020 7 0   Download

The catalytic activity and product selectivity depend on the reaction conditions and oxidant nature. The styrene conversion is moderate about 10-15 % and the total selectivity to benzaldehyde and styrene oxide reached 99 % as air and t-butyl hydrogen peroxide used as milder oxidants.

5p bautroibinhyen211 26-11-2018 27 1   Download

Mg0.6Al0.4(OH)2(MoO4)0.2.mH2O was prepared via coprecipitation method and characterized by XRD, BET, EDS techniques. The solid has a hydrotalcite-like structure and molybdate anions stayed in the interlayer regions between two brucite sheets. The synthesized material has been used as heterogeneous catalyst for the liquid oxidation of styrene with air. The oxidation reaction was carried out at atmospheric pressure in the temperature range of 60-110 oC.

5p giesumanh 04-11-2018 57 0   Download

The catalysts exhibited a very high activity in the conversion of styrene into two main products (benzaldehyde and styrene oxide). The highest styrene conversion was about 90 – 95 % and the total selectivity to benzaldehyde and styrene oxide was in the range of 80 – 85 % under reported experimental conditions.

8p cumeo4000 01-08-2018 50 0   Download

The substrate selectivity and enantioselectivity of Solanum tuberosum epoxide hydrolase 1 (StEH1) have been explored by steady-state and pre-steady-state measurements on a series of styrene oxide derivatives. A prefer-ence for the (S)- or (S,S)-enantiomers of styrene oxide, 2-methylstyrene oxide andtrans-stilbene oxide was established, with E-values of 43, 160 and 2.9, respectively.

12p vinaphone15 28-02-2013 33 1   Download