Approaches to improve performances of onboard hydrogen production by plasma reforming of dimethyl ether

Experiments of hydrogen production by partial reforming of dimethyl ether(DME) with recycle of exhaust heat were carried out by using self-made measurement system and onboard plasma system. The effects of heating temperature, air-to-DME volume ratio (V _A/V _D) and Fe-based catalyst on H ₂ yield, DME conversion rate, H ₂ selectivity and energy consumption were investigated. The results indicated that with the increase of heating temperature, the DME conversion rate was increased, the H ₂ yield increased first and then decreased, with the maximal value of 20.3% at 650°C. At 600°C, with the increase of V _A/V _D, the H ₂ yield increased initially and then decreased, with the maximal value of 22.2% at V _A/V _D of 3.0.The optimal V _A/V _D for the highest H ₂ yield could be decreased by heating method, but the H ₂ selectivity was decreased. The Fe-based catalyst clearly improved the reaction velocity when temperatures were beyond 500°C, and the H ₂ yield and DME conversion were both increased with the increase of heating temperature. The comprehensive performance of onboard hydrogen production system could be improved by exhaust heat recycle of engine, but the heating temperature should not exceed 650°C.