The Integrated coal Gasification Combined Cycle (IGCC) is one successful technology to replace conventional coal-fired power plants. In order to achieve better performance in the IGCC, the knowledge and behavior of volatile products are necessary. In the present study, experimental analysis of coal pyrolysis in a novel downer reactor was conducted. Dried Loy Yang coal particles (particle size D-p = 0.250-0.300mm) were pyrolyzed with a novel quartz glass downer reactor (1.0m in length and 20mm in inner diameter). The effect of activated carbon (AC) on coal pyrolysis was investigated. The main importance of this study is to understand the effects of pure carbon itself in a pyrolysis process focusing on tar capturing and reforming. Moreover, the study focuses on understanding how the pores of AC (i.e., micro and mesopores) interact with tar. During the experiment, AC was preheated at 1173 K in a fluidized bed heater before feeding to the downer reactor, and then the pyrolysis reaction and its product yields were observed. The results from the study indicate that AC can eliminate the light tar and significantly reduce the heavy tar. This can be attributed to the decomposition of aromatic hydrocarbons into coke.