Partial hydrogenation of acetylene over a NiTi-layered double hydroxide supported PdAg catalyst

Abstract

NiTi layered double hydroxide (NiTi-LDH) with rich defective sites was synthesized and used as the support for the preparation of a novel supported PdAg nanoalloys catalyst for the partial hydrogenation of acetylene. The obtained PdAg/NiTi-LDH catalyst exhibited a remarkable catalytic performance. When the conversion of acetylene reached 90%, the selectivity towards ethene maintained 82%. Superior hydrogenation activity was ascribed to two key factors. Small particle size and high dispersion of PdAg nanoparticles were responsible for boosting the catalytic activity. In addition, Ti 3+ defective sites in the support also played an important role on the enhancement of activity. The interface at the Ti 3+ species and active metals acting as new active sites enhanced the activation and dissociation of hydrogen and therefore further improved catalytic activity. Preferable selectivity was assigned to the electronic effect between NiTi-LDH support and PdAg nanoalloys. The electron transfer from the Ti 3+ species to Pd resulted in the increase of electron density and the linearly coordinated sites of Pd and therefore facilitated the desorption of ethene. Moreover, due to the reducibility of NiTi-LDH, the selectivity and stability over reduced PdAg/NiTi-LDH catalyst were further enhanced on account of the strong metal-support interaction.xM 3+ x(OH)2] x+ (A n-)x/n·mH2O. The M 2+ and M 3+ cations are uniformly dispersed within the layers. 14 Owing to the flexibility in composition

Nickel Based Catalysts for Selective Hydrogenation of Cinnamaldehyde- Influence of Support Phases

“…According to the H2 pulse chemisorption results, the Ni/TiO2 (Hombikat, Rutile and P25) catalysts have lower nickel dispersion than Ni/Al2O3 and Ni/SiO2 catalysts. 36 TEM results on the catalysts corroborate this aspect.…”

Fabrication of a PdAg mesocrystal catalyst for the partial hydrogenation of acetylene

“…In principle, both initial and final state effects can be responsible for BE shifts. Initial state [76]. g Pd/TiO 2 prepared by wet impregnation using the method of Anderson [21].…”

Развитие Подходов К Формированию Платиновых Центров С Заданными Свойствами С Использованием Носителей Со Слоистой Структурой

“…Основными направлениями использования нанесенных катализаторов на основе СДГ являются реакции окисления, гидрирования ненасыщенных С-С и С-О связей, нитросоединений а также реакции сочетания. В качестве нанесенного металла, в большинстве случаев используются палладий, золото, рутений, реже родий, платина, серебро и некоторые другие металлы и биметаллические композиции [10,[25][26][27][28].…”