A review of recent advances in hydrogen purification for selective removal of oxygen: Deoxo catalysts and reactor systems

Research on alkali metal-modified Pd catalyst for oxygen removal from propylene

“…Although water was continuously generated during the reaction, a small amount of water could not affect the activity of the Pd-based catalyst. When the additional water was introduced in the system, the amount of water Frontiers in Chemistry frontiersin.org molecules around the active sites increased, which resulted in the formation of a water film that covered the active site (Kim et al, 2022).…”

“…Schindler et al developed a Pt-Sn/α-Al 2 O 3 catalyst, by whose effect oxygen and hydrogen could react to produce water at a temperature between 250-300 °C, while a small amount of propylene might react with hydrogen (Schindler et al, 2011). Although there have been many technologies for oxygen removal in gas mixtures, most of the technologies were used for inert gas purification (Kim et al, 2022). In addition, disadvantages like high reaction temperature, frequent regeneration, or low performance (or selectivity) of the oxygen-removal reaction restricted the application of these technologies to the removal of oxygen in the tail gas of the HPPO process.…”

“…Pd-substituted Co 3 O 4 -ZrO 2 was used for catalytic hydrogen combustion, and Pd improved H 2 and O 2 activation, which reduced the temperature of the reaction; the activation energy of the Pd catalyst was decreased by more than 2-fold (Singh et al, 2017). If the advantage of the Pd catalyst on hydrogen oxidation and selective hydrogenation can be combined, it should be a good choice for oxygen removal from unsaturated hydrocarbon (Kim et al, 2022).…”

Stability of Pt10Sn3 Clusters Supported on γ‐Al2O3 in Oxidizing Environment: a DFT Comparison of Alloying and Size Effects

“…γ‐alumina supported Pt catalysts are also widely used for the oxidation reactions of various molecules such as hydrocarbons (methane, propane,…) [5] as well as carbon monoxide (CO) [6,7] . This type of catalytic material is also well‐known to be efficient for O 2 reduction reaction (ORR) [8] which is of renewed interest nowadays within the context of hydrogen purification [9] . Nevertheless, one open question remains about the oxidation state of platinum in oxidizing conditions.…”

“…[6,7] This type of catalytic material is also wellknown to be efficient for O 2 reduction reaction (ORR) [8] which is of renewed interest nowadays within the context of hydrogen purification. [9] Nevertheless, one open question remains about the oxidation state of platinum in oxidizing conditions. In particular, it has been reported by in situ XAS experiment that such alumina supported Pt may become partially oxidized upon oxygen environment encountered in CO oxidation reaction, [10] while density functional theory (DFT) calculations also showed that the oxidizability of Pt is increased for small size clusters.…”