Caroline Cellier

Characterisation of a gamma-MnO2 catalyst used in VOC abatement

This study presents the results of a comprehensive characterisation of a very efficient VOC abatement catalyst. The changes suffered by a γ-MnO 2 catalyst during VOC oxidation are determined and their impact on the catalytic activity is discussed. Sintering and partial reduction are detected. But they respectively have only a limited and no effect on the stability of the catalytic activity. Conversely, water vapour adsorption appears to cause very long (12h) stabilisation delays.

Preparation of Pd on Carbon Black by Deposition-precipitation: Study of the Effect of the Support Functionalisation

This work provides the comparison of palladium deposition-precipitation and ion exchange on functionalised or non functionalised carbon blacks or TiO2. Results show that functionalisation is mandatory for ion exchange, but that active carbon black supported noble metal catalysts can be prepared without functionalisation using deposition-precipitation.

Optimized conditions for the preparation of Pt supported catalysts by deposition-precipitation

Abstract The deposition-precipitation of platinum was investigated using two different platinum precursors: chloroplatinic acid and ammonium tetrachloroplatinate. While H 2 PtCl 6 did not allow a deposition-precipitation of platinum, a high deposition of platinum could be obtained using (NH 4 ) 2 PtCl 4 in defined conditions.

Ag/SiO2 and Cu/SiO2 cogelled xerogel catalysts for benzene combustion and 2-butanol dehydrogenation

Ag/SiO2 and Cu/SiO2 xerogel catalysts were synthesized by cogelation of tetraethoxysilane (TEOS) and chelates of Ag and Cu with 3-(2-aminoethylamino)propyltrimethoxysilane (EDAS). The resulting catalysts are composed of completely accessible metallic crystallites with a diameter of about 3 nm located inside silica particles exhibiting a monodisperse microporous distribution centered on a pore size of about 0.8 nm and larger metallic particles with a diameter of 20 to 40 nm located outside the silica network. The activity of Ag/SiO2 and Cu/SiO2 catalysts has been shown for benzene combustion and 2-butanol dehydrogenation.

Towards More Gold and Less Chlorine on the Support During the Deposition-Precipitation of Gold

Abstract Gold catalysts were prepared by deposition-precipitation combining NaOH, NH4OH or urea as precipitating agent and HAuCl4 or Au(CH3COO)3 as gold precursors. Comparison of the catalysts indicates that the deposition-precipitation with gold acetate and urea appears to be a promising alternative preparation method to the classical one. Besides allowing a higher deposition of gold than could be obtained with the classical method based on HAuCl4 and NaOH, this alternative method also provides Cl- and Na-free samples.

Influence of the Ti-precursor used for the grafting of SiO2 on the catalytic properties of Rh/Ti-SiO2 in the Partial Oxidation of Methane.

Abstract Ti-SiO2 samples have been synthesized by grafting SiO2 with either TiCl4 or Ti[OCH(CH3)2]4 as Ti source. These samples have been used as supports for the preparation of Rh-supported catalysts, which have been studied in the POM reaction. A higher Rh dispersion as well as a more reduced Rh was found for the catalyst prepared from TiCl4, which exhibits also a higher selectivity towards H2 and CO.