“…The catalysts that were reported to have high performance in removing tars from the producer gas were classified into three groups: (1) natural catalysts, such as CaO from CaCO 3 and CaO and MgO from dolomite; (2) alkali-based catalysts, such as Li, Na, and K; and (3) metal-based catalysts, such as nickel catalysts. ,− In this work, CaO was used as the catalyst. CaO not only acts as a CO 2 sorbent but also as a tar-reforming catalyst. , In addition, the catalytic reforming of tar using CaO not only reduces the tar amount in the product gas but also enhances the hydrogen and total gas yields. , Mahishi and Goswami reported the use of CaO for increasing H 2 and decreasing CO 2 from steam gasification of southern pine bark in a batch-type gasifier and showed the effect of CaO as bed material on produced gas: CO 2 decreased from 28.4 to 26.7 vol %, while H 2 increased from 62.0 to 65.5 vol % at 700 °C.…”