Abstract
Catalytic steam reforming of pyrolysis tar has been investigated using benzene and n-Heptane as model tar compounds. The effects of temperature, steam-to-carbon ratio (S/C) and weight hourly space velocity (WHSV) on the reforming reaction were clarified for each model compound. The commercial ruthenium-based catalyst was used. This catalyst is more active than the nickel-based catalyst and can suppress carbon deposition at the low S/C ratio. The two tar model compounds had different reaction rates. The product gas composition and yield vary with reformer temperature, S/C and WHSV. The carbon conversion rate increased with raising the temperature and decreasing WHSV. On the other hand, the change of S/C ratio little affected the carbon conversion rate. Benzene was more difficult to be reformed than n-Heptane. In the experiment performed at 800 ℃, S/C=3, WHSV=0.095 h^<-1>and model compound = n-Heptane, the results were that 12.6 mol/mol-Heptane for hydrogen yield and 88.4 % for the carbon conversion.
