Abstract
Taiheiyo coal was pyrolyzed in a fluidized-bed using nitrogen gas at temperature of 600 to 900°C. The tar was investigated by GPC and 1H n.m.r. spectroscopy. Tar yield at continuous feed of coal was reduced to about 60% of that at batch condition. In addition, 15 to 30% reductions in tar yield were observed at the presence of solid particles (ash, silica sand, char or coal). In the presence'of solid, increased thermolysis led to decomposition of aliphatic substituents, which resulted in both gaseous aliphatic hydrocarbons and smaller shorter quantity of alkyl substituted aromatic hydrocarbons. Consequently tar yield and its molecular weight distribution were lower and its aromaticity was higher compared with pyrolysis in the absence of solid particles.
