Synthesis of Alcohols and Alkanes from CO and H 2 over MoS 2 /γ-Al 2 O 3 Catalyst in a Packed Bed with Continuous Flow

Effects of reaction conditions on the production of alcohols (AOH s ) and alkanes (Alk) from CO and H 2 , which can be obtained from the gasification of biomass, using a molybdenum sulfide (MoS 2 )-based catalyst of MoS 2 /γ-Al 2 O 3 were studied. A high-pressure fixed packed bed (HPFPB) was employed to carry out the reaction. The results indicate that the conversion of CO (X CO ) and specific production rates of alcohol (SPR AOH ) and alkane (SPR Alk ) are highly depended on temperature (T). In T = 423–573 K, maximum yield of alcohols (Y AOH ) and SPR AOH occur at T = 523 K. In the meantime, well performance gives the selectivity of ethanol (S EtOH ) of 52.0 C%. For the studies on varying H 2 /CO mole ratio (M H/C ) from 1 to 4 at 523 K, the appropriate M H/C to produce EtOH is 2, giving higher ratios of SPR AOH /SPR Alk and Y AOH /Y Alk than those with other M H/C . As for varying the total gas flow rates (Q G ) of 300, 450, 600 to 900 cm 3 min −1 tested at T = 523 K and M H/C = 2, the lower QG provides longer reaction time (or gaseous retention time, t R ) thus offering higher X CO , however lower productivity. For setting pressure (P ST ) = 225–540 psi, a supply of higher pressure is equivalent to providing a larger amount of reactants into the reaction system, this thus suggests the use of higher P ST should give both higher X CO and productivity. The assessment of the above results indicates that the MoS 2 /γ-Al 2 O 3 catalyst favors the production of alcohols over alkanes, especially for ethanol. The information obtained is useful for the proper utilization of biomass derived gases of CO and H2.