Hydrogen production syngas compositions

The gasifier fuel gas quality is an important issue for the RP development. The effect of the fuel gas composition has been modeled. The modeling showed that the potential hydrogen production efficiency is strongly dependent on the combustion products/syngas (CP/SG) ratio [(C02+Hj0)/(C0+H2) = CP/SG] of the fuel gas. 

The composition of product syngas throughout the stages of a steam methane reformer designed to maximize production of hydrogen is shown in Table 3 [3]. 

Modern-day industrial-scale facilities for hydrogen or syngas production use multiple reactions to convert carbonaceous feedstock (e.g. natural gas) into the required composition. These reactions are typically equilibrium limited and this drives the operating temperatures and pressures that are used. 

The first attempts to hydroformylate quinazolinone-substituted allyl amines under smooth conditions (10-40bar, 60-80°C) led to hydrogenation [100]. Only higher temperature and a syngas composition not equal to 1 produced the desired product. Similar conditions also allowed HAM of this substrate with phenylhydrazine derivatives (Scheme 5.116). By this protocol, other aminobutyl-substituted quinazolin-4(3//)-ones with biological activity in the central nervous system could also be prepared. 

Yan F, Luo SY, Hu ZQ, Xiao B, Cheng G (2010) Hydrogen-rich gas production by steam gasification of char from biomass fast pyrolysis in a fixed-bed reactor influence of temperature and steam on hydrogen yield and syngas composition. Biores Technol 101 5633-5637... 

Although the Clean Fuels PEPS design is intended to produce syngas for F-T synthesis of liquid fuels, it should be noted that the system, with minor modifications, could be used to produce hydrogen as the primary product. The water gas shift reactor could be modified to drive the gas composition to primarily H2 and CO2. The addition of a hydrogen separation unit downstream of the shift reactor would permit recovery of hydrogen as an alternate product stream. 

M. He et al.. Syngas production from catalytic gasification of waste polyethylene influence of temperature on gas yield and composition. Int. J. Hydrogen Eneigy 34(3), 1342-1348 (2009)... 

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