Hydrogen Generation and Coke Formation over a Diesel Oxidation Catalyst under Fuel Rich Conditions

Abstract

Hydrogen production via hydrocarbon steam reforming and water gas shift reactions was investigated over a monolith-supported Pt-based diesel oxidation catalyst. The evaluation included comparison between constantly rich gas composition conditions and cycling between rich gas conditions and an inert stream. Analysis was performed along the catalyst length at temperatures ranging from 200 to 500 °C. During the constant inlet composition experiments, C3H6 steam reforming started at 375 °C, while dodecane steam reforming began at 450 °C, and resulted in less hydrogen produced. With a mixture of C3H6 and dodecane, hydrogen production originated solely from C3H6 steam reforming and, under otherwise identical conditions, was less than that observed with only C3H6, but higher than that with only dodecane. Hydrogen production from the water gas shift reaction was higher than that observed with hydrocarbon steam reforming and started at 225 °C. During cycling experiments, hydrogen production via hydrocarbon steam r...