Boreskov Institute of Catalysis of the Siberian Branch of Russian ...

KINETIC DECOMPOSITION OF FORMIC ACIDOVER VANADIA-TITANIA CATALYSTPP-I-16E.A. Ivanov, G.Ya. Popova, Yu.A. Chesalov, T.V. Andrushkevich, S.I. ReshetnikovBoreskov Institute of Catalysis SB RAS, Novosibirsk, Russian FederationFax: 007-383-3308056, e-mail: Eugene@catalysis.ruVanadia-titania catalysts are highly selective towards the oxidation of formaldehyde intoformic acid in the temperature range 100-140 °C. At higher temperatures the selectivitydecreases sharply because of the decomposition of formic acid [1]. The present work is aimedat the study of the decomposition of formic acid.The experiments were performed at 50÷190 °C in air flow containing 1 vol.% of theformaldehyde. A sample of the catalyst containing 20 wt.% of V 2 O 5 and 80 wt.% of TiO 2 wasprepared by the procedure described elsewhere [1] and then calcined at 450 °C.The kinetic scheme with the minimal amount of steps that appropriately describes theexperimental data was chosen. It includes 3 stepsHCOOH + [Z] ↔ [Z-HCOOH] → [Z] + H 2 O +CO.The first step involves an interaction of formaldehyde with active site [Z] with generate ofthe surface intermediate [Z-HCOOH]. Than, this intermediate is decomposed with water andcarbon monoxide formation.The kinetic equations was developed. The proposed kinetic model was used to estimatethe rate constants, reaction orders, activation energies and surface intermediates. Itsatisfactorily describes the experimental data.AcknowledgmentThe authors acknowledge to RFBR (Grant № 06-03-32473-а) for the financial support.References1. Popova G.Ya., Chesalov Yu.A., Andrushkevich T.V. and Stoyanov E.S. React. Kinet. Catal. Lett. 2002, 76,123-129.241