PARTICLE OF METAL OXIDE CARRIER OF CATALYST AND WASTE GAS TREATMENT CATALYST Russian patent published in 2010 - IPC B01J37/02 B01J21/04 B01J21/06 B01J23/58 B01J23/63 B01J23/96 

FIELD: metallurgy.

SUBSTANCE: invention refers to particles of metal oxide carrier of catalyst, method of such particle obtainment, waste gas treatment catalyst including metal oxide catalyst, and method of waste gas treatment catalyst recovery. Invention describes particle of metal oxide catalyst carrier, consisting of central part and external shell part, where both central and external shell parts include first metal oxide and second metal oxide, central part and external shell part differ in composition, molar fraction of first metal oxide is higher in central part than in external shell part, molar fraction of second metal oxide is higher in external shell part than in central part, and first metal oxide is aluminium or zirconium oxide while second metal oxide is selected out of group including neodymium, praseodymium, lanthanum, scandium and yttrium oxides. Invention describes waste gas treatment catalyst including the claimed particle of metal oxide carrier and platinum applied onto the particle of metal oxide catalyst carrier. Invention describes method of waste gas treatment catalyst recovery involving waste gas treatment catalyst heating at 500°C or higher in oxidation medium including oxygen. Also invention describes method of obtaining particle of metal oxide catalyst carrier, consisting of central part and external shell part, where both parts include first metal oxide and second metal oxide, central part and external shell part differ in composition. Method involves obtainment of material solution including at least colloid particles of first metal oxide and metal salts of second metal oxide, where first metal oxide is aluminium or zirconium oxide, second metal oxide is selected out of group including neodymium, praseodymium, lanthanum, scandium and yttrium oxides; achievement of solution pH close to isoelectric point of colloid particles of first metal oxide so as to coagulate colloid particles of the first metal oxide; solution pH increase so as to cause precipitation of colloid particles of the second metal oxide from metal salts and coagulate colloid particles of the second metal oxide around coagulated colloid particles of the first metal oxide, where isoelectric point of colloid particles of the second metal oxide is higher than isoelectric point of colloid particles of the first metal oxide; and coagulated product drying and calcination.

EFFECT: increased specific area of waste gas treatment catalyst surface, increased degree of platinum particle recovery.

10 cl, 19 ex, 2 tbl, 3 dwg