Improved H₂ utilization by Pd doping in cobalt catalysts for reductive amination of polypropylene glycol

Abstract

Addition of Pd into Co helped remarkably to reduce cobalt oxide and nitride to cobalt metal by enhanced hydrogen dissociation and desorption.

Reshaping the Role of CO2 in Propane Dehydrogenation: From Waste Gas to Platform Chemical

“…Contrarily, lower coke accumulation (CB and from CHN analysis of the spent materials) correlated linearly with higher H 2 uptake ( R 2 = 94%, Figure right). When comparing different active metal oxides, it is unclear how reducibility can play a role in coke formation, although H 2 -TPR is a technique that does not easily differentiate between H 2 that is consumed by a reaction or by adsorption. , In this regard, it has been shown that the high partial pressure of H 2 induces chemisorption, which prevents hard coke from forming on the surface of the catalyst and favors propylene desorption . That is arguably why the Pt-Sn 4 catalyst (high H 2 uptake) is the material of choice in industrial DHP plants that rely on external heating and aims to minimize coke formation, , although in our experiments this did not translate to lower deactivation rates.…”

Constructing a Pd–Co Interface to Tailor a d-Band Center for Highly Efficient Hydroconversion of Furfural over Cobalt Oxide-Supported Pd Catalysts

“…17,18 A similar electronic effect was observed for NiSn intermetallic compounds by Yang et al 19 For Co−M bimetals, Kim et al proposed that the insertion of a trace amount of Pd in Co could increase the valence electron density of Co due to the electron transfer from Pd to Co, facilitating the desorption of H on the highly charged antibonding orbital of Co−H. 20 A converse electron transfer direction was observed for Co−Pt bimetal by Wang et al and Yan et al 21,22 Similarly, metal−support interfacial effects including the modification of the electronic structure and geometrical configuration have been extensively observed mainly when reducible metal oxides were used as supports. 23−25 For the hydrogenation of furfural species, Wang et al proposed that the coexistence of Cu 0 and Cu + stabilized by the metal− support interaction significantly increased the catalytic activity of Cu/MCM-41.…”

“…Kunene et al reported that alloying Pt with Ni resulted in a downshift of the d-band center in comparison to Pt, thus weakening the adsorption of substrates . Tang et al and Fan et al attributed the enhanced activity of Cu-doped Ni catalysts for the furfural hydrogenation to the improved desorption of H, originating from the downshift of the Ni b-band center on account of the electron transfer from Cu to Ni. , A similar electronic effect was observed for NiSn intermetallic compounds by Yang et al For Co–M bimetals, Kim et al proposed that the insertion of a trace amount of Pd in Co could increase the valence electron density of Co due to the electron transfer from Pd to Co, facilitating the desorption of H on the highly charged antibonding orbital of Co–H . A converse electron transfer direction was observed for Co–Pt bimetal by Wang et al and Yan et al , …”

“…Besides electronic effects, multiple Cu–oxide interfaces (Cu–MgAlO x and Cu–CoAlO x ) were designed by Wang et al to regulate the reaction pathway of the furfural hydrogenation via the selective adsorption and activation of the functional groups on interfacial sites . Co 3 O 4 featuring the redox behaviors is deemed as a promising catalyst for various oxidation and hydrogenation reactions. , Furthermore, the enhanced reducibility of Co 3 O 4 as the support of noble metal catalysts, originating from the hydrogen spillover effect, favors the creation of the interface between the noble metal and metallic cobalt . To the best of our knowledge, the study of the metal–support interaction mainly focuses on the effects on the properties and catalytic performance of the metal component.…”

Research on key cobalt technologies based on patent analysis

“…Cobalt is currently being studied in various technological fields of technology and applications, such as catalysts, alloy materials, magnetic materials, medicine, and battery materials. Cobalt can be used as a catalyst to improve energy utilization, and Kim et al (2020) synthesized cobalt-based catalysts with enhancement by inserting traces of palladium. Kim et al (2018)also prepared cobalt-based catalysts with different base strengths by controlling the amount of yttrium oxide.…”