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, endothermic and accompanied by volume expansion. Therefore, higher temperatures and lower pressures shift it to completion. Higher temperatures, on the other hand, promote side reactions, coke formation, and catalyst deactivation. Catalytic PDH has been

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In the present study, ethylbenzene dehydrogenation to styrene monomer over a potassium-promoted iron oxide catalyst in radial fixed bed reactor was simulated. The pseudo-heterogeneous model was employed to predict ethylbenzene conversion and selectivity of styrene monomer, toluene, and benzene. The simulation results showed that deactivation of catalysts causes reduction in the reaction zone; therefore, the ethylbenzene conversion decreases. It is proposed that, for compensating the conversion reduction, the feed temperature is increased 1 °C per 5 cm of deactivated length. Simulation results are in good agreement with the experimental data obtained from real plant.

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by changing the space velocities (WHSV). In this study, WHSV is ranged between 3.5 and 4.5 h −1 , in order to avoid fast catalyst deactivation. The inlet temperature and pressure for each bed are identical to the reaction conditions mentioned above

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time-on-stream at a reaction temperature of 160 °C, a WHSV of 4.5 h −1 and a molar tert -butanol/phenol ratio of 2. When the reaction is on for 2 h, the conversion of phenol is 80.3%. After reaction for another 3 h, obvious catalyst deactivation is

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An integrated process including continuous-flow syntheses directly coupled to product isolation via continuous crystallization is presented. For the synthesis part, Ce0.495Sn0.495Pd0.01O2—δ was used as heterogeneous catalyst in a custom-made packed-bed reactor (the so-called “Plug and Play” reactor) for continuous Suzuki—Miyaura crosscouplings of various para- and ortho-substituted bromoarenes with phenylboronic acid using environmentally friendly aqueous ethanolic mixtures as reaction solvents. The reactions were stable for up to 30 h without any detectable catalyst deactivation. The desired biaryl products were obtained in gram scale with good to excellent yields and high selectivity. For three methyl-, ketyl-, and nitrile-functionalized biphenyl products, isolation was done using water as antisolvent in an integrated crystallization process as continuous downstream protocol. The desired products could be isolated with high purity and with yields of up to 95% for the overall process.

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Reaction Kinetics, Mechanisms and Catalysis
Authors: Viorel Chihaia, Karl Sohlberg, Monica Dan, Maria Mihet, Alexandru R. Biris, Petru Marginean, Valer Almasan, George Borodi, Fumiya Watanabe, Alexandru S. Biris, and Mihaela D. Lazar

catalyst deactivation [ 10 – 13 ]. The addition of cerium oxide and lanthanum oxide to alumina supported noble metal catalysts (Pt and Pd) was reported to improve the catalyst stability for MSR [ 14 , 15 ]. For Ni catalysts, the promoting effect of cerium

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polymerization ” J.i-H. Kang , E. Reichmanis* Angewandte Chemie International Edition 2012 , 51 , 11841 – 11844 . “ Asymmetric α-amination of aldehydes catalyzed by PS-diphenylprolinol silyl ethers: remediation of catalyst

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to the dehydrogenation of isobutane to isobutene. Because the direct dehydrogenation of isobutane is an endothermic and volume-expanding reaction, it is usually performed at high temperature; hence fast catalyst deactivation due to

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Reaction Kinetics, Mechanisms and Catalysis
Authors: Shakeel Ahmed, Faizur Rahman, Adnan M. J. Al-Amer, Eid M. Al-Mutairi, Uwais Baduruthamal, and Khurshid Alam

that of non-oxidative dehydrogenation and additionally minimize coke formation and catalyst deactivation [ 6 ]. Another challenge with OXDH is to minimize the formation of carbon monoxide, carbon dioxide and water. However, efforts are needed to improve

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dioxide hydrogenation at the reaction temperature of 250 °C and reaction pressure of 30 bar is shown in Fig. 4 . It was revealed that Zr improved the Cu 0 area in the catalysts and catalytic performance without experiencing severe catalyst deactivation

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