Production of Synthetic Alcohol from Ayngas Using MoS2/<em>andgamma;</em>-Al<sub>2</sub>O<sub>3</sub>

S. W. Chiang
Graduate Institute of Environmental Engineering, Nation Taiwan University, Taiwan

C. C. Chang
Graduate Institute of Environmental Engineering, Nation Taiwan University, Taiwan

H. Y. Chang
Graduate Institute of Environmental Engineering, Nation Taiwan University, Taiwan

C. Y. Chang
Graduate Institute of Environmental Engineering, Nation Taiwan University, Taiwan

Ladda ner artikelhttp://dx.doi.org/10.3384/ecp11057537

Ingår i: World Renewable Energy Congress - Sweden; 8-13 May; 2011; Linköping; Sweden

Linköping Electronic Conference Proceedings 57:72, s. 537-545

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Publicerad: 2011-11-03

ISBN: 978-91-7393-070-3

ISSN: 1650-3686 (tryckt), 1650-3740 (online)


This study examined the transformation of the biomass gasification synthesis gas (syngas; CO and H2) to liquid fuels and chemicals via the high pressure fixed packed bed (HPFPB). The MoS2/?-Al2O3 catalyst was packed in the packed bed (PB) to enhance the selectivity (S) and yield (Y) products. The effect of reaction temperature (T); pressure (PST ); gas flow rate (QG) and H2/CO (vol./vol.) ratio oon the system performance were investigated. Typical reaction conditions unless otherwise specified were as follows: T = 423; 473; 523 and 573 K; PST = 3 Mpa; QG = 300 cm3 min -1; and mass of catalyst (mS) = 30 g.

The main products include CH4; C2H6 and C2H5OH (EtOH) that EtOH being the target product. The results indicate that with packing MoS2/?-Al2O3 catalyst in PB; the conversion of CO (XCO) and alcohol production rate (R) are highly depended on T. At T = 573 K; XCO = 8.19%; R of CH4 (RCH4) = 194.1 mg h-1 and selectivity of CH4 (SCH4) = 34.57%. For the production rate of C2H5OH (REtOH); the maximum REtOH of 134.25 mg h-1 takes place at T = 523 K while XCO = 8.10% and SEtOH = 51.98%. As T increase to 573 K; the EtOH is further decomposed into simple hydrocarbons (HCs) such as C1-C3 alkanes. Thus; for producing more alcohols and less alkanes; the optimal temperature condition is 523 K. For the case of varying H2/CO ratio; the values of XCO are about 7.55 to 8.32%) at 523 K with H2/CO ratios of 1 to 4; indicating no significant variation. However; the optimal ratio of H2 and CO to produce EtOH is 2 with maximum REtOH = 134.25 mg h-1 and SEtOH = 51.98% while XCO = 8.10%; RCH4 = 56.05 mg h-1 and SCH4 = 10.85%. Hence; increasing the H2/CO ratio to 3 to 4 is not beneficial for the formation of EtOH. The results also show that a higher PST of HPFPB yields more products. For the EtOH production; the maximum REtOH (= 156.65 mg h-1) occurs at PST = 3.6 Mpa with corresponding SEtOH = 51.16%; XCO = 9.57%; RCH4 = 70.31 mg h-1 and SCH4 = 12.46%. Among various QG of 300; 450; 600 to 900 mL min-1 of HPFPB tested; the best XCO is at QG = 300 mL min-1 with XCO = 8.10%; RCH4 = 56.05 mg h-1 and SCH4 = 10.85%. Also; the maximum YEtOH take place at QG = 300 mL min-1 with corresponding SEtOH = 51.98%. It shows that a low flow rate gives a longer residence time for reaction of the syngas and thus enhances the yield of products. However; there’s no advance for SEtOH.

For the production of EtOH from syngas; the YEtOH; SEtOH and REtOH are key factors for the success of process. The results of this study shows that MoS2/γ-Al2O3 catalyst can give satisfactory SEtOH and REtOH; especially the YEtOH high selectivity.


Reforming of syngas; Synthesis of alcohol; MoS2/Al2O.; catalytic synthesis; alcohol; alkane


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