III International Conference

PP-III-46INFLUENCE OF SUPPORT NATURE AND PREPARATION METHOD OFINDIUM-CONTAINING CATALYSTS ON THEIR ACTIVITY IN NO SCR BYLIGHT HYDROCARBONSMironyuk T.V., Anich I.H., Orlyk S.N.L.V. Pisarzhevskii Institute f Physical Chemistry of the NAS Ukraine, Kiev, UkraineE-mail: myroniuk@inphyschem-nas.kiev.uaIt was shown that activity of the In-containing catalysts in SCR of NO x -C 1 -C 4hydrocarbons depends on the amount of indium, nature of the support and preparationmethod. The In 2 O 3 /Al 2 O 3 catalysts exhibited the high H 2 O-tolerance.The problem of NO x reduction in lean conditions (SCR-process) in the precence of watersteam and SO 2 , is still under conversation. The attractive feature of the indium containingcatalysts is their tolerance to SO 2 and H 2 O [1].In this study we have investigated the influence of support nature (Al 2 O 3 and ZrO 2 ) andthe method of indium loading in support’s matrix (wet-impregnation and coprecipitation) oncatalytic performance in SCR of NO by light hydrocarbons (methane, propane-butanemixture, propene) also in the precence of SO 2 and H 2 O.The results of electron microscopy investigations (ТEM-125К) testify to polydisperseframe of support: the conglomerates of the carrier of the different size (up to 100-120 nm)consist of 10 nm size Al 2 O 3 particles and also separate single crystals. According to the dataof XRD powder diffraction the main Al 2 O 3 phase is γ-Al 2 O 3 , and ZrO 2 the monoclinemodification.The activity of indium-doped alumina catalysts on SCR of NO by propene was stronglydependent on the In 2 O 3 loading. The maximum NO conversion was obtained for the 2.5wt. %and 5wt. % In 2 O 3 -соntained catalysts (conversion of NO was 67-69% at 350-400ºC). Activitydecreasing of coprecipitated sample (5%In 2 O 3 -95%Al 2 O 3 ) in SCR of NO by C 3 H 8 incomparing with analogous one, obtained by impregnation of In 2 O 3 from the solution, can beexplained by the lower value of the In 2 O 3 surface concentration in it. 5% In 2 O 3 /ZrO 2 sampleshowed the low activity for NO reduction by propene (maximum of NO conversion is 11% at400 о С).Fig.1 (curves 1, 3, 4) presents the temperature dependences of NO conversion for5%In 2 O 3 /Al 2 O 3 catalyst with different hydrocarbons: methane, propane–butane mixture andpropene. They indicate a higher activity of olefins in comparison with alkanes in SCR process555