| abstract |
A process for producing an ultrafine mixed-crystalnoxide characterized by producing an ultrafine mixed crystalnoxide comprising primary particles in a mixed crystal statenand having a BET specific surface area of 10 to 200 m 2 /g,ncomprising the step of subjecting a halogenated metal tonhigh temperature oxidation with an oxidizing gas to producena metal oxide by a vapor phase production method, whereinnthe halogenated metal is in the form of a mixed gas (anmixed halogenated metal gas) comprising at least twoncompounds having a metal element different from each othernwhich are selected from the group consisting of chlorides,nbromides, and iodides of titanium, silicon, and aluminum,nand the mixed halogenated metal gas and the oxidizing gasnare independently preheated to 500°C or more prior to anreaction, a ultrafine mixed crystal oxide obtained by thenprocess, and use of the oxide. |