Multiporous Carbon Encapsulated Ni Nanoparticles Promoting Glycerol Valorisation towards Hydrogenation against Rearrangement†. Issue 5 (10th April 2020)

• Record Type: Journal Article
• Authors: Zhang, Bin; Chen, Bin; Douthwaite, Mark; Tang, Lipeng; Zhang, Yibo; Wang, Meng; Ma, Ding
• Is Part Of: Chinese journal of chemistry. Volume 38:Issue 5(2020)
• Page Start: 439
• Page End: 444
• Publication Date: 2020-04-10
• Subjects: Heterogeneous catalysis -- Ni catalysts -- Hydrogenation -- Glycerol hydrogenolysis -- Multiporous carbon; Chemistry -- Periodicals; 540.5
• DOI: 10.1002/cjoc.201900437
• Languages: English
• ISSNs: 1001-604X

Abstract

Summary of main observation and conclusion: A dual‐templating method was used to synthesize a series of hierarchical carbon supports containing different proportions of spherical macropores ( ca. 200 nm in diameter) and mesoporous channels ( ca. 4 nm in diameter). These and some other conventional carbon materials were subsequently impregnated with Ni and tested for the conversion of glycerol. The hierarchical catalysts exhibited a significantly higher conversion (96%) and selectivity (77%) to 1, 2‐propanediol, and the specificity selectivity coefficient (6.1) towards 1, 2‐propanediol against lactic acid was three times higher than that observed over a conventional Ni/Cmicro catalyst (2.1). The enhanced performance of these materials, compared with the Ni nanoparticles supported on conventional carbon supports, was attributed to their high surface areas (> 1110 m 2 ∙g −1 ) and large pore volumes ( ca . 0.4 cm 3 ∙g −1 ) permitting greater accessibility of substrate and/or intermediates to Ni active sites. Given that the concentration of accessible Ni sites in these materials is higher, a competitive benzilic‐acid‐rearrangement reaction to produce lactic acid was suppressed, leading to an enhanced hydrogenation selectivity to 1, 2‐propanediol. This study evidences the potential benefits, which can be established from utilizing hierarchical support materials in the valorization of biomass. Abstract : Ni‐based multiporous carbon catalysts containing macropores (~200 nm) and mesoporous channels (~4 nm) are highly selective and stable for glycerol conversion towards the hydrogenation to 1, 2‐propanediol against rearrangement to lactic acid in alkaline condition.