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Abstract  

Knowledge of material safety properties is critical for safe handing in the chemical process industries, especially for flammable chemicals that might result in serious fires and explosions. This study investigated the flammability characteristics of methanol under working conditions during the process. The targeted fire and explosion properties, like explosion limits (UEL and LEL), vapor deflagration index (K g), maximum explosion pressure (P max), and maximum explosion pressure rise [(dP dt −1)max], were deliberately obtained via a 20-L-Apparatus in 101 kPa (i.e., 760 mmHg/1 atm), 150 and 200 °C, along with various experimental arrangements containing nitrogen (N2) or carbon dioxide (CO2) as inert component. Particularly, this study discussed and elucidated the inert influence on the above safety-related parameters by two different inerting gases of N2 and CO2. The results indicated that adding an inert component to fuel–inert gas mixtures determined the decrease of explosion range and flammability hazard degree. The results also demonstrated that CO2 possessed higher inerting capability than N2 in this study.

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Abstract  

The effect of initial temperatures (100, 150, and 200 °C), operating pressures (101 and 202 kPa), and various loading oxygen concentrations (21, 17, 14…oxygen vol.%) on the flammability hazard evaluations for the mixtures of benzene and methanol (100/0, 75/25, 50/50, 25/75, and 0/100 vol.%) by using rough set method, was studied. The results indicated that the most important influence factor was the operating pressure. There is no significant difference in the safety assessment for the different concentrations of mixtures. This study proposed a helpful reference for a related practical plant combined with experimentally and theoretically feasible way for flammability prevention and protection.

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Abstract  

It is shown that metal oxide composites CuO–ZnO–CeO2/Al2O3 and Cu–ZnO/Al2O3, supported by cordierite monoliths, catalyze the production of hydrogen with selectivity and yield close to 90% and above for the decomposition and the partial oxidation of methanol. In methanol decomposition on CuO–ZnO–CeO2/Al2O3/cordierite, nanosized ceria acts as a key component stabilizing catalyst operation by suppressing carbonization of a surface, facilitating hydrogen production with a yield of 85–96%. At the same time, copper and zinc oxides are shown to act as modifying/promoting additives reducing the temperature of full conversion of the alcohol as well as minimizing the formation of methane as a by-product. Concerning partial oxidation of methanol over Cu–ZnO/Al2O3/cordierite, zinc oxide (as a constituent of ZnAl2O4 aluminate) is shown to be a “self-sufficient” catalytic component playing a key role in the high-yield H2 producing. A non-additive effect of decrease in selectivity concerning CO (as a by-product) on the binary Cu–ZnO catalyst, as compared with the samples derived from individual components Cu and ZnO, is found.

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Introduction Methanol synthesis from carbon monoxide and hydrogen is one of the most important processes in chemical industry. The conversion of the reactants in a conventional tubular fixed-bed reactor is limited by the

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Abstract  

The highest propylene selectivity and best catalytic stability were gained over Ca modified ZSM-5 that had little free Brønsted acid sites, which indicated that Ca interacted with Brønsted acid sites and thus participated in the catalytic reaction as supported by the MTO data of Na modified ZSM-5. A possible mechanism that involves the formation of acid-base centers by hydrolyzing Ca species in the presence of water is suggested.

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dioxide is its hydrogenation into valuable compounds such as methanol, generally on copper based catalysts. The synthesis of methanol from CO/CO 2 /H 2 mixtures using CuO/ZnO/Al 2 O 3 catalysts is currently attracting much interest due to its economical

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point out that the direct synthesis process is more favorable than the traditional methanol dehydration process [ 1 , 2 ]. DME production will be dependent on the activity of the methanol synthesis catalyst because the methanol formation has been

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, H. & Delgado, J. M. (1997): Different methanol feeding strategies to recombinant Pichia pastoris cultures producing high level of dextranase. Biotech. Tech. , 11 , 461-466. Different methanol feeding strategies to

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Introduction The methanol-to-hydrocarbons reaction was first discovered in the laboratory of Mobil Company using a ZSM-5 catalyst [ 1 ]. Higher temperature and lower pressure were proved to have positive effects on the olefin

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. & Fanelli, R. (1986): Serum methanol concentrations in rats and in men after a single dose of aspartame. Fd Chem. Toxicol. , 24 , 187–189. Fanelli R. Serum methanol

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