New nanodispersed Cu–ZrO2 systems (containing 0 and 8.3 mol% Cu) were synthesized by sol–gel method. Homogeneous gels were prepared starting from Zr propoxide and Cu(NO3)22.5H2O. The materials were characterized by XRD, TG/DTA, N2 adsorption, TPR techniques and N2O surface oxidation. In the Cu-containing material part of Cu2+ ions were incorporated into the zirconia lattice and strongly influenced the crystallisation behaviour of zirconia matrix. After treatment at 450–600 8C, the materials contained ZrO2 nanocrystals of the tetragonal polymorph. The samples heat treated up to 450 8C showed high surface areas in the range 140–180 m2/g. Copper oxide species with different reducibility were detected by TPRmeasurements. The H2 reduction treatments gave rise tometallic copper with very high dispersion. The catalysts showed high activity for the oxidative steam reforming of methanol. A noticeable activity was observed also with the not pre-reduced catalyst, although a previous reduction in H2 led to a higher selectivity and H2 production.
Higly Dispersed Sol-Gel Synthesized Cu-ZrO2 Materials as Catalysis For Oxidative Steam Reforming of Methanol
ESPOSITO, Serena;
2010-01-01
Abstract
New nanodispersed Cu–ZrO2 systems (containing 0 and 8.3 mol% Cu) were synthesized by sol–gel method. Homogeneous gels were prepared starting from Zr propoxide and Cu(NO3)22.5H2O. The materials were characterized by XRD, TG/DTA, N2 adsorption, TPR techniques and N2O surface oxidation. In the Cu-containing material part of Cu2+ ions were incorporated into the zirconia lattice and strongly influenced the crystallisation behaviour of zirconia matrix. After treatment at 450–600 8C, the materials contained ZrO2 nanocrystals of the tetragonal polymorph. The samples heat treated up to 450 8C showed high surface areas in the range 140–180 m2/g. Copper oxide species with different reducibility were detected by TPRmeasurements. The H2 reduction treatments gave rise tometallic copper with very high dispersion. The catalysts showed high activity for the oxidative steam reforming of methanol. A noticeable activity was observed also with the not pre-reduced catalyst, although a previous reduction in H2 led to a higher selectivity and H2 production.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
