PROGRESS IN STEAM-METHANE REFORMING FOR GREEN HYDROGEN PRODUCTION AT LOW TEMPERATURE

Abstract

             Adsorption-enhanced steam-methane reforming process has recently been investigated for low temperature hydrogen production from hydrocarbons with simultaneous CO2 abatement.

This process is based on a concept involving simultaneous hydrogen production and CO2 removal, which can combine both catalyst and adsorbent in the stationary phase for in turn reaction stage and regeneration stage of adsorbent (case 1) or can use a stationary catalyst phase in combination with a continuously circulated and regenerated moving adsorbent phase (case 2). This paper summaries the recent technology development including experimental results and simulating work on adsorption-enhanced steam-methane reforming for low temperature hydrogen production using both cases with two different fixed-bed reactors.

This work uses a mixture of an industrial nickelbased catalyst and hydrotalcite as the packed and CO2 adsorbent particles (case 1) and an industrial nickel-based catalyst as the packed particles and hydrotalcite as the suspended CO2 adsorbent particles (case 2), whereas methane (main composition of natural gas) is used as the model feedstocks for technological experiments.

The results show that an equilibrium methane conversion increases when increasing reaction temperature, steam-to-methane ratio, nitrogen flowrate and decreases when increasing the reactor pressure. The removal of CO2 from reaction zone enhances the equilibrium methane conversion and the more the amount of CO2 has been removed, the higher methane conversion and the more hydrogen with higher purity have been produced. The results also show that the thermodynamic, experimental and simulation data are fairly matched with each other.