Isobutanol synthesis catalyst

The invention relates to a catalyst for conversion of methanol, ethanol alone or in combination with n-propanol to isobutanol and the process for making and using the catalyst. The catalyst is a noble metal supported on at least a first phase of mixed oxide crystallites containing from about 60 to about 74 atomic % (on a metals basis only) zirconium, from about 21 to about 31 atomic % manganese and from about 5 to about 9 atomic % zinc, and less than about 1 atomic % alkali, a second phase of zirconium-doped hetaerolite particles containing from about 65 to about 69 atomic % manganese, from about 31 to about 35 atomic % zinc, from about 0.5 to about 5 atomic % zirconium, and optionally a trace atomic % of alkali, and a third phase containing from about 29 to about 55 atomic % manganese, from about 13 to about 55 atomic % zinc and from about 13 to about 35 atomic % zirconium. The first phase mixed oxide crystallites have a zirconium oxide-like structure have a particle size of at least about 40 ANGSTROM to about 100 ANGSTROM , wherein the second phase particles have a particle size of about 200 ANGSTROM to greater than about 2000 ANGSTROM , and the third phase has a particle size of about 1000 ANGSTROM to greater than 4000 ANGSTROM .