High-Yield Hydrogen Production by Steam Gasification of HyperCoal (Ash-Free Coal Extract) with Potassium Carbonate:  Comparison with Raw Coal

Abstract

Steam gasification of the HyperCoals (ash-free coal extracts) with the physical addition of 5.8%−6.0% K 2 CO 3 was conducted at 1023 K on a thermogravimetric apparatus that was equipped with an on-line quadrupole mass spectrometer. The catalytic gasification of the HyperCoals demonstrated a much higher gasification rate than the catalytic gasification of the raw coals. Interactions of K 2 CO 3 with mineral matter in the raw coal formed water-insoluble potassium compounds, such as potassium aluminosilicates, and reduced the catalytic activity, whereas no such negative reactions occurred for the HyperCoals. The steam gasification of the HyperCoals with K 2 CO 3 was also determined to be favorable for the high-yield production of hydrogen. From these experimental results, the catalytic steam gasification of HyperCoal would potentially be a more efficient process for the production of hydrogen in the future.