Hydrogen from pyrolysis

Tai yields of approximately 0.32 m /1 were quoted. Because the scheme used hydrogen, the pyrolysis Hquids generally exhibited lower heteroatom contents than conventional tars derived from coal pyrolysis ia an iaert atmosphere. Process development proceeded through a 270 t/d semiworks plant which was operated successfully on noncaking coals. OperabiUty for caking coals was difficult, however. 

Thus, the hydrogenation of isomeric l-ethynyl-3-methyl- and l-ethynyl-5-methylpyrazoles by hydrogen with 10% Pd/C in l-ethyl-3-methyl- and 1-ethyl-5-methylpyrazoles was used to prove the structure of iV-ethynylpyrazoles formed from pyrolysis of the corresponding iV-propynoylazoles (94AJC991) (Scheme 79). 

Figure 2 Methyl coverage in monolayers (ML) as a function of methyl exposure, in langmuirs (L) of mixture of gases from pyrolysis source. Symbols are data showing the sum of methane formed plus residual carbon. Consistent values are obtained by summing hydrogen appearing in CH4 and H2 gas-phase products. Solid line is a guide to the eye.

Fig. 5.2 The main crop-to-energy chains. BtL Biomass-to-Liquid, GtL Gas-to-Liquid, ETBE Ethyl tert-butyl ether, MTBE Methyl tert-butyl ether, MeOH Methanol, DME Dimethyl ether. Pyrolysis oil, HTU-Diesel (Hydro Thermal Upgrading), ethanol and hydrogen from ligno-cellulosic species are not considered here because of their minor practical relevance in the near future...

A combination of pyrolysis and gasification is applied to produce hydrogen from solid fuels. In the past, a variety of methods has been used to gasify solid fuels, to... 

Comparison of pyrolysis and air-steam gasification shows that the yield of hydrogen from biomass is generally higher by air-steam gasification than that by pyrolysis, because with interaction of water and char from decomposition of biomass intermediate products are formed, which leads to more hydrogen-rich gas yield by the steam reforming. 

Plots for yield of hydrogen from supercritical fluid (water) extraction, pyrolysis gasification (water/solid = 2) of beech wood at different temperatures... 

Demirbas, M.F. 2006a. Hydrogen from various biomass species via pyrolysis and steam gasification processes. Energy Sources Part A 28 245-252. 

Demirbas, A., Arin, G. 2004. Hydrogen from biomass via pyrolysis relationships between yield of hydrogen and temperature. Energy Sources 26 1061-1069. 

Wang, D., Czernik, S., Chornet, E. 1998. Production of hydrogen from biomass by catalytic steam reforming of fast pyrolysis oils. Energy Fuels 12 19-24. 

Direct extrusion of methyl nitrene has been discounted as an explanation of these deamination reactions, which are apparently induced by attack of the acetylenic ester and thus more likely take place via an intermediate analogous to 176. On the other hand, the products from pyrolysis of 107 at 325° include 1,2,3,4-tetrafiuoronaphthalene (132) and hydrogen cyanide, and it was suggested that methyl nitrene was the precursor of the latter compound (see Section III,D). The adduct (180) of tetrafiuorobenzyne and thiophen extrudes sulfur so readily... 

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