1 Effect of Selected Factors on Catalytic Activity of 2 Bimetallic Copper - Gold Catalysts in Selective 3 Oxidation of Glycerol 4

A current problem in petrochemical industry is the elimination of crude glycerol which is 11 the by-product of biodiesel production obtained during the transesterification of vegetable oils and 12 animal fats. In this work are presented the results of characterisation of mesoporous ceria, zirconia 13 and mixed cerium-zirconium oxide modified with gold and/or copper species and their application 14 as catalysts in the selective oxidation of glycerol in the liquid phase. The characterisation of 15 samples was performed using selected advanced techniques (ATR-FTIR, UV-vis, XRD, adsorption 16 and desorption of nitrogen, XRD, XPS, TEM, SEM, STEM-EDXS). The obtained data show that the 17 bimetallic Cu-Au systems supported on mesoporous ceria, zirconia or mixed cerium-zirconium 18 oxide are more active and selective in glycerol oxidation to glyceric acid in basic solution than 19 acidic conditions. The data of HPLC analysis provided that glyceric acid was the first stable 20 product in the liquid phase during the oxidation process in alkali media. It is worth noting that the 21 bimetallic Cu-Au catalysts were characterised also by the catalytic stability, because the increase of 22 selectivity to glyceric acid during the recycling of Cu-Au catalysts was achieved. The influence of 23 selected factors (oxygen source, pH solution, oxygen pressure, base content and stirring speed) on 24 the catalytic activity of Cu-Au catalysts will be presented and discussed. 25