Direct dehydrogenation of isobutane to isobutene over Zn-doped ZrO₂ metal oxide heterogeneous catalysts

Abstract

A series of unconventional nano-sized Zn-doped ZnZrO-x catalysts are applied for the first time to the direct dehydrogenation of isobutane to isobutene.

The Role of the Oxygen Vacancies in the Synthesis of 1, 3‐Butadiene from Ethanol

“…Considering the EPR results (Figure ) and according to Silva‐Calpa et al., McFarland & Metiu and Liu et al., it can be suggested that Zn +2 substitutes Zr +4 in the t ‐ZrO 2 lattice generating oxygen vacancies and coordinatively unsaturated Zr 4+ ions (cus). The oxygen vacancies can be associated with strong basic sites whereas the cus species with Lewis acid sites.…”

“…Indeed, replacing Zr +4 with Zn +2 makes the ZrO 2 surface more electrophilic. As oxygen is also electrophilic, it is easily displaced from the oxide surface generating vacancies . Silva‐Calpa et al .…”

“…Recently, Liu et al . have showed that the ZnZrO 2 catalyst exhibits high activity for the alkanes dehydrogenation, which was associated with oxygen vacancies and cus pairs generated by the presence of Zn +2 in the ZrO 2 lattice.…”

The tendency of supports to generate oxygen vacancies and the catalytic performance of Ni/ZrO2 and Ni/Mg(Al)O in CO2 methanation

“…Alternatively, the O vacancies are associated with CO dissociation or formate decomposition to methoxy species, both suggested as the rate-limiting step of the methanation reaction. The CO 2 methanation mechanisms employing vacancy–cus pairs 12 are described in detail in the Results and discussion section.…”

Effect of Reduction Atmosphere on Structure and Catalytic Performance of PtIn/Mg(Al)O/ZnO for Propane Dehydrogenation

“…The support materials, Al 2 O 3 [11], SiO 2 [6], ZrO 2 [12,13] and zeolite [3,14], can also affect catalytic performance on account of the significant differences in textural properties. Especially, the Mg(Al)O (c) by-product selectivity (reduction conditions: T = 600 °C, t = 2.5 h; reaction conditions: T = 600 °C, weight hourly space velocity (WSHV) = 3 h −1 , atmospheric pressure in the gas mixture of C3H8:H2:N2 molar ratio = 8:7:35; reaction time: 30 h for H2/N2 and 14 vol % H2/N2 reduced catalyst, 26 h for C3H8/H2/N2-reduced catalyst, 17 h for C3H8 and CO-reduced catalyst).…”