Pyrolysis of lignocellulosics

State of the art of applied fast pyrolysis of lignocellulosic materials—A review. Bioresource Technol. 1999, 68, 71-77. 

Lignin classification based on the quantities of the three phenylpropanoid units, namely 4-hydroxyphenylpropane (H), guaiacylpropane (G), and syringylpropane (S), formed in the pyrolysis of lignocellulosic materials... 

Bilbao A., Millera A. and Arauzo J. (1988) Product Distribution in the Flash Pyrolysis of Lignocellulosic Materials in a Fluidised Bed, Fuel, 67, 1586-1588. 

Di Blasi C. (1998) Comparison of semi-global mechanisms for primary pyrolysis of lignocellulosic fuels. J. Anal. Appl Pyrolysis, 47, 43-64. 

Simple thermal pyrolysis of lignocellulosics with or without additives has been reviewed by several authors (15-17). In contrast to microwave pyrolysis, reasonably extensive conventional pyrolysis product characterization has been conducted for certain types of biomass (15-25) and some of these results will be compared to those cited here. To these authors knowledge, no single study on microwave pyrolysis (plasma or di-electric loss mode) has identified the components of all product fractions nor their relative amounts work reported here has been extended by others (43,44) to include pyrolysis studies of biomass fractions and other types of biomass with the emphasis on detailed product characterization, formation kinetics, and effect of transport rates. 

Cheng Y-T, Jae J, Shi J, Fan W, Huber GW (2012) Production of renewable aromatic compounds by catalytic fast pyrolysis of lignocellulosic biomass with bifiinctional Ga/ZSM-5 catalysts. Angew Chem Int Ed 51(6) 1387-1390... 

Positive ESI-MS has also been applied on bio-oils obtained by pyrolysis of lignocellulose. The spectra obtained from positive and negative ESI-MS of a bio-oil are shown in Figure 34.2. Both spectra demonstrate very complex patterns (unfragmented), which reflect the high complexity of the sample. Each line in the spectrum may represent several chemical compounds with the same MW (isomers). The spectra also contain patterns that represent distributions of related compounds. These patterns often contain specific repetitive differences in mass, and a A 14 is often found, as in this example. This A 14 corresponds to different numbers of CH2 units, indicating the presence of homologous series [14,15]. 

Crude bio-oil (BO) obtained by flash pyrolysis of lignocellulosic biomass contains large proportions of aldehydic compounds. These were successfully hydrogenated to the corresponding alcohols in a water-dichloromethane biphasic system with a catalyst prepared in situ from RuCl3-3H20 and TPPTS at 45-70°C and 0.6 MPa H2 (93). 

Table 8.3 Major chemicals from the pyrolysis of lignocellulosic biomass ...

Pyrolysis of lignocellulosic biomass leads to an array of useful products including liquid and solid derivatives and fuel gases. At the beginning of the twentieth century, pyrolysis processes were utilized for the commercial production of a wide range of fuels, solvents, chemicals, and other products from biomass feedstocks. At the time, the dry distillation of wood for the production of charcoal was the mainstay of the chemical industry. 

Various chemistries and processes can be applied to convert lignocellulosic materials into valuable fuels and chemicals [3, 19]. For instance, thermal reactions are exploited in the pyrolysis of biomass to charcoal, oil and/or gases and its gasifica-... 

Conversion of lignocellulose into biocrude via pyrolysis and hydrothermal treatment [30-32, 72]. 

Conversion of lignocellulose into transportation fuels via pyrolysis and subsequent oil upgrading [72], via gasification and subsequent Fischer-Tropsch or methanol synthesis [3], via hydrolysis and subsequent fermentation to ethanol or subsequent conversion into ethyl levulinate [45, 46, 73]. 

Boon, J. J., 1989, An introduction to pyrolysis mass spectroscopy of lignocellulosic material case studis of barley straw, com stem and Agropyron, in Physico-chemical Characterisation of Plant Residues for Industrial and Feed Use, A. Chesson, and E. R. 0rskov, eds., Elsevier Applied Science London, pp. 25-49. 

Telysheva, G., Dobele, G., Meier, D., Dizhbite,T., Rossinka, G., and Jurkjane, V. (2007). Characterization of the transformation of lignocellulosic structures upon degradation in planted soil. J. Anal. Appl. Pyrolysis 79, 52-60. 

Galletti, G. C., and Bocchini, R (1995). Pyrolysis/gas chromatography/mass spectrometry of lignocellulose. Rapid Comm. Mass Spectrom. 9, 815-826. 

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