ZRO2 PROMOTED WITH SULFATE, IRON AND MANGANESE - A SOLID SUPERACID CATALYST CAPABLE OF LOW-TEMPERATURE N-BUTANE ISOMERIZATION

A sulfated oxide of zirconium, iron and manganese is prepared and shown to isomerize n-butane to isobutane at 35-degrees-C with rates approximately 2-3 orders of magnitude greater than sulfated zirconia as claimed by workers at Sun Refining and Marketing Company. Temperature programmed desorption of benzene is used to investigate the acidity of this remarkable catalyst. Adsorbed benzene is oxidized to CO2 by the triply promoted oxide catalyst; CO2, SO2 and 02 are found to desorb at 525, 575 and 560-degrees-C, respectively. Sulfated zirconia does not adsorb benzene in a similar manner. The results from the temperature programmed desorption of benzene cannot be correlated with the n-butane isomerization activity.