Different Doses Of Γ-rays Research Articles

CuO-Al 2O 3 catalyst containing 16.2 wt% CuO, precalcined at 300°C was subjected to different doses of γ-rays ranging between 20 and 160 Mrad. The magnetic properties were measured by the Gouy method and the catalytic activity and selectivity towards isopropanol conversion were investigated using a microcatalytic pulse technique at temperatures between 260–300°C. The CuO-Al 2O 3 system exhibited a lower paramagnetic moment compared to that of unloaded CuO. γ-Irradiation induced changes in the magnetic properties of the system. The presence of diamagnetic alumina as a support and its dehydroxylation with γ-rays contributed to the observed changes in the magnetic properties. Loading of CuO on alumina decreased the dehydration activity which disappeared completely at 16.2 wt% CuO. γ-Irradiation resulted in a progressive decrease in the dehydrogenation activity falling to a minimum at a dose of 40 Mrad. At greater doses the activity increased with the increase of the irradiation dose. Unirradiated and 160 Mrad-irradiated samples measured more or less the same dehydrogenation activity.

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