Question

I understand that charcoal/biochar are mostly amorphous carbon, and that the production of graphite via pyrolysis requires using a <60% C feedstock that will exists in liquid phase during at least a portion of the pyrolysis heating.

However, if a stable (mechanically), mostly-solid piece of carbon were the only goal of the process, could a liquefiable feedstock be used to wet out, and bind together powdered charcoal, or bio-char in a second pyrolysis/carbonization cyle? And if so, are there any resources where I could find information about the physical properties the resulting final product would display?

Answer 1

Yes, it is possible to use a liquefiable feedstock in pyrolysis to wet out and bind powdered charcoal or biochar. The product's properties would depend on feedstock and process conditions, and specialized materials science resources would be needed to understand the specifics.

Step-by-step explanation:

The process of using a liquefiable feedstock in pyrolysis to wet out and bind powdered charcoal or biochar is indeed plausible. The resulting product from such a process would likely display properties influenced by both the feedstock used and the conditions of the pyrolysis cycle. If using a feedstock such as coal tar or heavy petroleum fractions, which can be liquefied under pyrolytic conditions, they could serve as the binder for the powdered charcoal or biochar, resulting in potentially higher mechanical stability of the solid mass. This carbonization process would essentially be forming a composite material where the char particles are embedded within the carbonized matrix of the feedstock.

Physical properties of the final product would vary based on the nature of the feedstock as well as the processing parameters such as temperature, pressure, and duration of pyrolysis. However, finding specific information on the physical properties of such a composite material may require consulting specialized materials science literature or conducting experimental trials, as this application is quite specific and may not have widely available data. Resources like LibreTexts and scientific journals dealing with material science and carbon materials may offer some guidelines and references for the expected properties and behavior of carbonized composites.

It is important to note that techniques such as coal gasification and liquefaction are primarily aimed at converting coal into syngas, methane, or liquid fuels rather than enhancing the physical properties of solid carbon materials. However, the principle of liquefying carbon-rich materials to create binders for solid composites does draw on related concepts.