Catalytic Conversion of Isopropyl Alcohol over CuO/MgO Treated with K2O

Abstract

CuO/MgO system having different extent of CuO varying between 0.025 to 0.3 mol/mol MgO were prepared by impregnation method followed by calcination at 400-800 ºC. The effect of CuO content, calcination temperature and doping with small amounts of K2O (1-3 mol % )on physicochemical surface and catalytic properties of the system have been investigated using XRD, adsorption of N2 at -196ºC, and catalytic conversion of isopropyl alcohol at 150-400 ºC using a flow technique. The results revealed that the solids having formula 0.2 and 0.3 CuO/MgO calcined at 400 consisted of MgO and CuO as major phases together with Cu2O as minor phase. The degree of crystallinity and crystallite size increase by increasing the calcination temperature within 400-800 ºC. The BETsurface areas of different adsorbents decreased progressively as a function of CuO loading and calcination temperature. Furthermore, K2O-doping decreased the degree of crystallinity of CuO phase present with subsequent increase in the crystallite size of MgO from 23 to 37.5 nm in case of solid having the formula 0.2 CuO / MgO calcined at 400 ºC. MgO-support material showed very small catalytic activity in isopropyl alcohol conversion. The investigated system behaved as selective catalyst for dehydrogenation of isopropyl alcohol with selectivity > 80%. The catalytic activity increases progressively as a function of extent of loading and decreases by increasing calcination temperature above 400 ºC. K2O- doping much increases the catalytic activity.