Palladium volatile organic compounds

Catalysts for the oxidation of volatile organic compounds (VOC) are generally supported platinum or palladium catalysts. Copper oxide, vanadium oxide and chromium oxide are suitable for the oxidation of halogenated compounds. 

Catalysts for total hydrocarbon and volatile organic compounds (VOC) combustion in waste gases contain noble metals supported on alumina. The noble metals are platinum, palladium, combinations of platinum and palladium, or rhodium and the typical content is 0.3-0.5 wt%. The BASF RO-25 catalyst, specified for VOC combustion, is reported to contain 0.5% palladium on 0-AI2O3 characterized by a surface area of 109 w g (428). 

Garcia, T., Solsona, B., Cazorlaamoros, D., Linaressolano, A., and Taylor, S. (2006) Total oxidation of volatile organic compounds by vanadium promoted palladium-titania catalysts comparison of aromatic and polyaromatic compounds. Appl Catal B Environ., 62 (1-2), 66-76. 

The development of active catalysts for total combustion of volatile organic compounds (VOCs) has been desired from foe viewpoint of environmental protection. Noble metal which possess high activity for total oxidation are widely applied to foe low temperature complete oxidation [1]. Moreover, it was shown that supports play an important role in catalytic activity and zeolites were widely used as powerful catalytic support [2-4]. Therefore, zeolites FAU and BEA exchanged with different alkali metal cations were prepared and 0.5wt% of palladium was incorporated in these supports. The catalysts obtained were calcined, characterised and tested for propene total oxidation. Some of these solids were also tested for VOCs adsorption. 

The most successful class of active ingredient for both oxidation and reduction is that of the noble metals silver, gold, ruthenium, rhodium, palladium, osmium, iridium, and platinum. Platinum and palladium readily oxidize carbon monoxide, all the hydrocarbons except methane, and the partially oxygenated organic compounds such as aldehydes and alcohols. Under reducing conditions, platinum can convert NO to N2 and to NH3. Platinum and palladium are used in small quantities as promoters for less active base metal oxide catalysts. Platinum is also a candidate for simultaneous oxidation and reduction when the oxidant/re-ductant ratio is within 1% of stoichiometry. The other four elements of the platinum family are in short supply. Ruthenium produces the least NH3 concentration in NO reduction in comparison with other catalysts, but it forms volatile toxic oxides. 

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