Japan Coal + Cellulose Coliquefaction / CO2 Recycling Synergy

ScienceDirect - Fuel : Co-liquefaction of coal and cellulose in supercritical water

 

Following up on our report of work at the University of Pittsburgh, concerning the potential for liquefying coal in combination with botanical cellulose to produce liquid transportation fuels, while thus recycling Carbon Dioxide, we submit this report, from Japan, on the same technology, to illustrate that it is well-understood, and that the work at Pitt was not just an isolated academic exercise.

 

The excerpt:

 

"Co-liquefaction of coal and cellulose in supercritical water 

Abstract

Co-liquefaction of biomass and coal in supercritical water is proposed with the intention that hydrogen matching between biomass and coal takes place, resulting in enhanced coal liquefaction and preferable liquefaction products. A semi-batch packed-bed reactor is employed to co-liquefy cellulose utilized for a model compound of biomass and Ishikari coal in supercritical water at 673 K and 25 MPa. No interaction between coal and cellulose is observed for the production of residue and water-insoluble product, judging from the yield and its composition. On the contrary, the yield of the water-soluble product increased for the case of co-liquefaction. Both hydrogen to carbon ratio and oxygen to carbon ratio of the water-soluble product increased by co-liquefaction. The mechanism for this interaction is proposed based on the addition reaction of compounds derived from cellulose with coal-derived compounds to increase the recoverable yield of the water-soluble product."

"Supercritical water", without being too specific, is just water heated beyond the boiling point but kept pressurized enough so that it can't turn to steam.

In other words, the biomass cellulose is intended, as we have earlier documented in other reports, to serve both as a donor of Hydrogen for the liquefaction of coal, and as a route of Carbon recycling.

And, subsequent to this and our other recent submissions concerning the synergistic potentials inherent in the co-liquefaction of coal and cellulose, we wanted to point out that, as with coal, US patents exist which describe the liquefaction of cellulose, and which, like some coal liquefaction technologies, present that the by-products of liquefaction can serve to increase the efficiency of liquefying additional raw material feed, be it coal or cellulose. To that end, we remind you of the following, earlier-submitted, US Patent:

"Title: Liquefaction of Cellulose

Patent: US5336819

Issue Date: August 09, 1994

Abstract: The conversion of cellulose to hydrocarbon fuel, particularly fuel oil can be carried out using a polycyclic hydrogen donor substance. The present invention rests on the discovery that a light cut of the product oil can be used in place of the polycyclic hydrogen donor substance thus making it much easier to run the process continuously."

One point being: We have earlier documented that "anthracene oil", a coal tar derivative, can serve to enhance the direct liquefaction of coal in a hydrogen donor solvent, such as the "tetralin" specified by West Virginia University, in their WV Process for Coal Liquefaction.

 

The conversion of both cellulose and coal, to liquid hydrocarbons, can, thus, be conducted concurrently, and the conversion process can be enhanced and made more efficient, perhaps almost in a self-sustaining way, as in: "a light cut of the product oil can be used ... (to make it) ... much easier to run the process continuously".

 

And, it would be a "process" that runs "continuously" to produce domestic liquid fuels from our most abundant natural resource, coal, while recycling the most abundant and contention-inspiring by-product of coal use, Carbon Dioxide, through the inclusion of renewable and environmentally-correct botanical cellulose.