Pyrolysis reactor stability

An IR spectroscopic study of the radicals CF3, C2F5, C3F7 and i-C3F7 has been carried out. These radicals were formed as products of vacuum pyrolysis in a platinum reactor of the respective fluorinated iodoalkanes and were stabilized in argon matrices at 10-12 K (Snelson, 1970b Butler and Snelson, 1980a,b,c) as shown in (6). 

M. Predel and W. Kaminsky, Pyrolysis of mixed polyolefins in a fluidized - bed reactor and on a pyro-GC/MS to yield ahphatic waxes. Polymer Degradation and Stability, 70, 373 (2000). 

W. Kaminsky, M. Predel and A. Sadiki Feedstock Recycling of Polymers by Pyrolysis in a Fluidised Bed Reactor. Polym. Degrad. Stabil, 85, 1045 (2004). 

Given the specifics of the fast pyrolysis process in terms of feedstock requirements and process conditions, ie, fast heating and short residence time in reactor, it can be expected to yield biochar with a different set of properties compared to other conversion processes, such as slow pyrolysis or gasification. The short residence time can lead to incomplete charring of the biomass particle, as observed by Bruun et al. (2011,2012). This in turn leads to lower environmental stability of biochar, and therefore lower carbon sequestration potential. This is the case even when the biomass conversion during pyrolysis is apparently complete, as reported in Brewer et al. (2009). These authors observed lower stability of fast pyrolysis biochar, assessed based on fixed carbon content and aromaticity, compared to slow pyrolysis and gasification biochar produced from the same feedstock. 

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