US Patent 7861517 Method and system for controlling catalyst temperature

A method for controlling temperature of a catalyst. The method includes monitoring temperature of the catalyst and determining that the catalyst is outside of a catalyst operating temperature window. If the catalyst temperature is high enough for exothermic reaction to occur, reformate is injected into the catalyst. If the catalyst not high enough for exothermic reaction to occur, reformate is injected upstream of the catalyst and ignited.