The effects of reaction temperature (T) on the yields of liquefaction products can be inferred from Fig. 2, which presents the results obtained from the liquefaction operations at various temperatures ranging from 513 K to 633 K without catalyst. R1 and R2 were fixed at 10% and 20%, respectively. Over the whole range of the investigated temperatures, the SR yield was decreased monotonically with increasing temperature. However, a different trend was presented for the bio-oil yield. The bio-oil yield appeared to be maximized at approximate 593 K. When the reaction temperature was further elevated to 633 K, the yield of bio-oil was decreased slightly. The yield of (Gas + Water) showed an increase from 15.90% to 44.80% as the reaction temperature increased from 513 K to 633 K.