Patent ID: 8609575

Claim:
A complex metal oxide catalyst having resistance to loss of activity due to contact with sulfur for treating an exhaust gas containing sulphur or sulphur compounds, nitrogen oxides (NOx), carbon monoxide (CO) and hydrocarbons, the catalyst comprising one or more complex oxides having a nominal composition as set out in formula (1): A x A′ w B 1-y-z M y P z O n (1) wherein: A is selected from one or more group III elements including the lanthanide elements; A′ is selected from Sr, Ba, and Ca; B is selected from Ti, V, W and Mo; M is selected from one or more elements with atomic number 25 to 30; P is selected from one or more elements with atomic number 44 to 50 and 76 to 83; x is defined as a number where 0<x≦1; w is defined as a number where 0<w≦1; 0.5<x+w≦1; y is defined as a number where 0≦y<5; z is defined as a number where 0<z<0.2; and n is a number that gives charge neutrality.