Nitrate hydrogenation over Pt,In/Al2O3 and Pt,In/SiO2.

F.A. MARCHESINI , S. IRUSTA, C. QUERINI, E. MIRO

CATALYSIS COMMUNICATIONS

Año: 2007 vol. 9 p. 1021 - 1026

1566-7367

In this work, bimetallic Pt,In catalysts supported on alumina and silica were studied for the reduction of nitrate to N2 in water, using H2 as reducing agent. Kinetic and characterization results suggest that the active sites are bimetallic particles with the surface enriched in Indium, probably Pt2In3 and/or Pt3In7 species. Of all the catalysts studied in this work, Pt(1 wt.%)In(0.25 wt.%)/Al2O3 is the most active one. At low time-on-stream it has a very high conversion rate, but it decreases with time due to the segregation of Pt and Indium oxide phases under reacting conditions in the aqueous media. The remarkable high activity of this catalyst during the initial stage of the reaction makes this system very interesting for further studies on the reaction mechanism including the possibility of regenerating the active sites.2 in water, using H2 as reducing agent. Kinetic and characterization results suggest that the active sites are bimetallic particles with the surface enriched in Indium, probably Pt2In3 and/or Pt3In7 species. Of all the catalysts studied in this work, Pt(1 wt.%)In(0.25 wt.%)/Al2O3 is the most active one. At low time-on-stream it has a very high conversion rate, but it decreases with time due to the segregation of Pt and Indium oxide phases under reacting conditions in the aqueous media. The remarkable high activity of this catalyst during the initial stage of the reaction makes this system very interesting for further studies on the reaction mechanism including the possibility of regenerating the active sites.2 as reducing agent. Kinetic and characterization results suggest that the active sites are bimetallic particles with the surface enriched in Indium, probably Pt2In3 and/or Pt3In7 species. Of all the catalysts studied in this work, Pt(1 wt.%)In(0.25 wt.%)/Al2O3 is the most active one. At low time-on-stream it has a very high conversion rate, but it decreases with time due to the segregation of Pt and Indium oxide phases under reacting conditions in the aqueous media. The remarkable high activity of this catalyst during the initial stage of the reaction makes this system very interesting for further studies on the reaction mechanism including the possibility of regenerating the active sites.2In3 and/or Pt3In7 species. Of all the catalysts studied in this work, Pt(1 wt.%)In(0.25 wt.%)/Al2O3 is the most active one. At low time-on-stream it has a very high conversion rate, but it decreases with time due to the segregation of Pt and Indium oxide phases under reacting conditions in the aqueous media. The remarkable high activity of this catalyst during the initial stage of the reaction makes this system very interesting for further studies on the reaction mechanism including the possibility of regenerating the active sites.