THE STRUCTURE AND ACTIVITY OF CATALYTICALLY ACTIVE SOLIDS

Includes AD-21-219(a) and AD-21-219(b). Samples of Fe sub2 O s ub3/Al sub2 O sub3 in concentrations up to 33% Fe and free from ferromagnetism were studied to determine the effects of CO on their magnetic properties. The ferromagnetism observed when the oxide was reduced to Fe/Al sub2 O sub3 diminished or disappeared after admitting CO to the sample tube. This magnetism returned as strong or stronger when the tube was freed of CO. In addition to the ferromagnetism, the sample's percentage Fe and susceptibility were determined as well as the specific magnetization and magnetic moment of the Fe. The results of all the specimens, except one, were obtained with one apparatus and were confirmed on a second. Samples reduced at 410 deg C tended towards a higher specific magnetization and a lower magnetic moment than those reduced at 350 deg C. The effect of heating for 5 hr in H at 350 deg C on a sample which had already had this treatment was the same as that of heating for 5 hr in He at the same temperature. Heating the original Al sub2 O sub 3 for 5 hr in H at 350 deg C caused little change in either specific magnetization or magnetic moment.