Studies On Novel Processes For Efficient Hydrogen Production From Hydrocarbon Fuels Over Nickel-based Reforming Catalysts

Large scale hydrogen production processes such as naphtha or natural gas steam reforming are well established in chemical industry. However, these technologies are unsuitable for hydrogen production on a smaller scale for application to fuel cells due to the high cost of hydrogen storage, delivery and distribution, as well as the specific requirement of hydrogen for application to fuel cells. In order to boost the commercialization of fuel cell technologies, intensive investigation on novel processes for economic and efficient hydrogen production onsite are performed worldwide.In this work, hydrogen production processes using hydrocarbon fuels and nickel reforming catalysts are investigated. Two novel processes are proposed and experimentally demonstrated on a lab scale.(1) Taking into account the problems that coke deposits on the stainless-steel reactor wall and nickel reforming catalysts in the process of hydrogen production from the autothermal reforming of liquid hydrocarbon fuels, which are ascribed to the high tendency of coke deposition of alkenes resulted from the gas phase side reactions during preheating the feedstock, we first proposed a novel autothermal reforming process in which prereforming and air distributed feed are applied. The long-term stability of the prereforming catalyst and autothermal reforming catalyst in the process are investigated for time-on-stream of 500 h. The results indicated that the process has good stability. The introduction of prereforming completely solved the problem of coke deposition on nickel reforming catalysts and reactor wall. Air distributed feed avoided the safety problems associated with the fuel flammability and reaction runaway. Series of Ni/Al₂O₃ and Ni/La-Al₂O₃ catalysts prepared by...