Stability of Transition-metal Carbides in Liquid Phase Reactions Relevant for Biomass-Based Conversion

作者：Macedo Luana Souza; Stellwagen Daniel R; da Silva Victor Teixeira; Bitter Johannes H^*

来源：ChemCatChem, 2015, 7(18): 2816-2823.

DOI：10.1002/cctc.201500566

• carbides
• biomass conversion
• heterogeneous catalysis
• transition metals
• sustainable chemistry

Transition-metal carbides have been employed for biobased conversions aiming to replace the rare noble metals. However, when reactions are in liquid phase, many authors have observed catalyst deactivation. The main routes of deactivation in liquid phase biobased conversions are coke deposition, crystallite growth, leaching and oxidation. This Minireview identifies and discusses the main trends between routes of deactivation and catalyst properties. The nature of the support can influence catalyst deactivation by coke deposition and leaching (role of acidity or electronic effects). Although carbon based supports seem to be a good choice for carbides in coke-sensitive reactions, deactivation by leaching is facilitated. The crystallite size of the carbide is related to deactivation by oxidation, larger crystallites (10 nm) have a higher resistance to oxidation than smaller crystallites (< 2 nm).

• 出版日期2015-9-14