Ni-supported catalysts on mesoporous carbon modified by Al(H2PO4)3 to obtain 1-propanol.

[Display omitted] • Ni 3 P, Ni 12 P 5 and Ni 2 P phases, identified by XRD and XAFS, are selective towards 1-propanol. • The presence of AlPO x and NiPO x species, determined by XAFS, increase the surface acidity. • Yield to 1-propanol decreases when surface acidity is higher than 1.3 × 103 mmol m−2. • With high surface acidity, selectivity towards 1-propanol decreases due to the formation of lateral dehydration products. The aim of this work was to investigate the catalytic properties of nickel over a carbon-based support modified with phosphorus for the hydrogenolysis of glycerol to obtain 1-propanol. For this, a series of nickel phosphide catalysts with different compositions were prepared employing Al(H 2 PO 4) 3 and NiCl 2 supported on mesoporous carbon and characterized by N 2 adsorption-desorption, acid-base properties measurements, TEM, XRD and XAFS analysis. These Ni catalysts presented different phases (Ni x P y , NiPO x , AlPO x), responsible of the increase in surface acidity, which depended on the Al(H 2 PO 4) 3 content. For Al(H 2 PO 4) 3 contents between 4 and 10 wt.%, an increase in surface acidity occurs that favors both the conversion and the selectivity of glycerol towards 1-propanol. These results show that the presence of the phosphates is necessary to reach high levels of catalytic activity. However, for Al(H 2 PO 4) 3 contents higher than 10 wt.%, a fall or loss of selectivity was produced due to the strong contribution of dehydration reactions on the support acid sites. The Ni/CPAl(10) catalyst, allows reaching 97 % conversion of glycerol with a selectivity of 74 % towards 1-propanol, employing an 80 wt.% glycerol aqueous solution, after 6 h of reaction. [ABSTRACT FROM AUTHOR]