Related Experiment Video
Updated: Aug 21, 2026

Fabrication and Testing of Catalytic Aerogels Prepared Via Rapid Supercritical Extraction
Published on: August 31, 2018
[Selective catalytic reduction of NO on Ag, Co and Cu/Al2O3 in excess oxygen]
Xiang-yu Cui1, Ji-ming Hao, Li-xin Fu
1Department of Environmental Science and Engineering, Tsinghua University, Beijing 100084, China.
Abstract:
The catalytic activities of alumina-supported Ag, Co and Cu for selective reduction of NO with propene as reductant in the presence of excess oxygen were investigated. The catalytic performances of single-component catalysts with different metal loadings and of samples prepared by various methods such as mechanical mixing, one-step impregnation, two-step impregnation, etc. were studied. The experimental results showed that the Ag exhibited the highest conversion of NO to N2 (approximately 89% with 2% loading, wt.) among single-component catalysts, the lower was Co, and the lowest was Cu. The sequence of the temperature for the maximum conversion was on the order of Cu < Co < Ag. For Ag catalysts, the activities between samples of identical loadings prepared by one-step and two-step impregnation were almost the same. The activities of mixed samples were not the simple sum of the single-component catalysts. The mixed Ag-Co sample possessed the highest activity (80% above). The activities of the combinatorial samples declined comparatively to some extent. The activities of one-step impregnation samples descended more markedly and the highest conversion was only over 30%.
Related Concept Videos
Reduction of Alkenes: Catalytic Hydrogenation
Metals like palladium, platinum, and nickel are commonly used in their solid forms — fine powder on an inert surface. As these catalysts remain insoluble in the reaction mixture, they are referred to as heterogeneous catalysts.
The hydrogenation process takes place on the surface of...
Reduction of Alkenes: Asymmetric Catalytic Hydrogenation
The metal catalyst used can be either heterogeneous or homogeneous. When hydrogenation of an alkene generates a chiral center, a pair of enantiomeric products is expected to form. However, an enantiomeric excess of one of the products can be facilitated using an enantioselective reaction or an...
Reduction of Alkynes to cis-Alkenes: Catalytic Hydrogenation
Like alkenes, alkynes can be reduced to alkanes in the presence of transition metal catalysts such as Pt, Pd, or Ni. The reaction involves two sequential syn additions of hydrogen via a cis-alkene intermediate.
Oxymercuration-Reduction of Alkenes
Alcohols from Carbonyl Compounds: Reduction
Catalytic hydrogenation is similar to the reduction of an alkene or alkyne by adding H2 across the pi bond in the presence of transition metal catalysts like Raney Ni, Pd–C, Pt, or Ru. Aldehydes and ketones can be reduced by this method, often under mild to moderate heat (25–100°C) and...
Aldehydes and Ketones to Alkanes: Wolff–Kishner Reduction

