Patent ID: 7271126

Claim:
A method of making a catalyst for use in the dehydrogenation of ethylbenzene to styrene, said catalyst comprising from about 20 wt % to about 90 wt % iron oxide calculated as Fe 2 O 3 , from about 5 wt % to about 20 wt % of an alkali metal compound calculated as an alkali metal oxide, from about 0.1 ppm to about 1,000 ppm of a source of palladium or platinum selected from the group consisting of elemental palladium, elemental platinum, compounds containing palladium, compounds containing platinum and combinations thereof, from about 0.5 wt % to about 10.0 wt % of a molybdenum compound or tungsten compound or a combination thereof, calculated as MoO 3 or WO 3 , and from about 4.0 wt % to about 20 wt % of a cerium compound, calculated as CeO 2 , wherein all weight percents are based on the total weight of the catalyst, and said method comprising: a) preparing an aqueous organic acid solution, wherein said organic acid is a carboxylic acid having at least one carboxylic acid group with a pK a at ambient temperature of from about 0.5 to about 6; b) adding iron metal to said acid solution; c) forcing an oxidizing agent through said acid solution until said iron metal is consumed and an iron slurry is formed; d) spray drying said iron slurry with a wheel atomizer to form iron oxide having a surface area of from about 2 m 2 /g to about 40 m 2 /g; e) calcining said iron oxide at a temperature of about 1200° F. until the calcined iron oxide has a surface area of from about 2 m 2 /g to about 80 m 2 /g; f) mixing the iron oxide with said alkali metal compound, and with said palladium or platinum, and with said molybdenum compound or tungsten compound or combination of molybdenum and tungsten compounds, and with said cerium compound, and optionally, with a promoter to form a mixture; g) forming said mixture into catalyst pellets by pressure forming; and h) calcining said catalyst pellets to form said catalyst.