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Biomass constitutes a renewable source for new chemical platforms. Among other processes the catalytic ones represent a green alternative when active and selective catalysts can be developed. In this paper, applications of gold and gold‐based catalysts have been reviewed in the field of the selective oxidations. Indeed, from the discovery of the peculiarity of gold as catalytic material, the liquid phase oxidations have been differently viewed. Three important biomass‐derived molecules, namely glucose, hydroxymethyl furfural (HMF) and glycerol have been considered as precursors for products of industrial interest where gold catalysts have played an important role. This review starts from the research on monometallic gold catalysts which have been explored initially and then look at gold as modifier of other metal catalyst. This latter field is still in evolution and probably needs to be look at in the future. Golden path: Applications of gold and gold‐based catalysts for selective liquid‐phase oxidation of biomass‐derived products have been reviewed. Three important molecules, namely glucose, hydroxymethyl furfural (HMF) and glycerol have been considered as precursors for products of industrial interest. [ABSTRACT FROM AUTHOR]

Adipic acid (AA) is one of the highest volume chemicals in world use with a wide range of commercial applications. This paper demonstrates the possibility of producing significant proportions of AA by the selective oxidation of cyclohexane (CH) in one step using various supported gold-nanoparticle (AuNP) catalysts. The catalysts were characterized by ICP, BET, XRD, X-ray photoelectron microscopy, and TEM. The catalytic activity tests were carried out in the liquid phase using autoclaves in the temperature range of 100-170 °C at 10 bar. A CH conversion of over 25 %, with 26% selectivity of AA and 70% selectivity of KA oil (cyclohexanone+cyclohexanol), was achieved over a nano-gold/TiO2 (anatase) catalyst. The superior performance of this catalyst is attributed to the smaller size of AuNPs, which has an average particle size of 2 nm. Good correlation between activity and Au particle size could be achieved. Overall, the particle size of the AuNPs showed a strong influence on catalytic performance. [ABSTRACT FROM AUTHOR]