Nov
26
Two Steps From Wood to Gasoline
November 26, 2014 | 2 Comments
Researchers at the Netherland’s KU Leuven’s Centre for Surface Chemistry and Catalysis have successfully converted sawdust into building blocks for gasoline. With the invention of a new chemical process, they were able to convert the cellulose of wood sawdust into hydrocarbon chains. These hydrocarbons can be used as an additive in gasoline, or as a component in plastics.
The cellulose component of the sawdust is the main substance in plant matter and is present in all non-edible plant parts of wood, straw, grass, cotton and old paper.
Professor Bert Sels explained, “At the molecular level, cellulose contains strong carbon chains. We sought to conserve these chains, but drop the oxygen bonded to them, which is undesirable in high-grade gasoline. Our researcher Beau Op de Beeck developed a new method to derive these hydrocarbon chains from cellulose.”
The researcher’s paper has been published in the journal Energy & Environmental Science.
Dr. Bert Lagrain takes the explanation deeper with, “This is a new type of bio-refining, and we currently have a patent pending for it. We have also built a chemical reactor in our lab: we feed sawdust collected from a sawmill into the reactor and add a catalyst – a substance that sets off and speeds the chemical reaction. With the right temperature and pressure, it takes about half a day to convert the cellulose in the wood shavings into saturated hydrocarbon chains, or alkanes. Essentially, the method allows us to make a ‘petrochemical’ product using biomass – thus bridging the worlds of bio-economics and petro chemistry.”
Using a one-pot biphasic catalytic system the catalytic reaction proceeds at elevated temperatures under hydrogen pressure in the presence of tungstosilicic acid, dissolved in the aqueous phase, and modified Ru/C, suspended in the organic phase.
The tungstosilicic acid is primarily responsible for cellulose hydrolysis and dehydration steps, while the modified Ru/C selectively hydrogenates intermediates en route to the liquid alkanes. Under optimal conditions, microcrystalline cellulose is converted to 82% n-decane-soluble products, mainly n-hexane, within a few hours, with a minimum formation of gaseous and char products.
The result is an intermediary product that requires one last simple step to become fully-distilled gasoline, explains Sels. “Our product offers an intermediate solution for as long as our automobiles run on liquid gasoline. It can be used as a green additive – a replacement for a portion of traditionally-refined gasoline.”
But the possible applications go beyond gasoline: “The green hydrocarbon can also be used in the production of ethylene, propylene and benzene – the building blocks for plastic, rubber, insulation foam, nylon, coatings and so forth.” Sels added.
“From an economic standpoint, cellulose has much potential. Cellulose is available everywhere; it is essentially plant waste, meaning it does not compete with food crops in the way that first generation energy crops – crops grown for bioethanol, for example – do.” Sels said.
“It also produces chains of 5 to 6 hydrocarbon atoms – ‘light nafta’ in the technical jargon. We are currently facing shortages in this because it is becoming quite difficult and more expensive to distil these specific hydrocarbon chains from crude oil or shale gas. In time, hydrocarbon derived from cellulose may provide an alternative,” Sels added.
Professor Bert Sels concluded with, “Our method could be especially useful in Europe, where we have little crude oil and cannot easily produce shale gas.”
Your humble writer hopes this idea can go to commercial scale. There have been a lot of these kinds of ideas come up working in the lab and end there as well. One of the ideas will go. Maybe its this one, time will tell.
Comments
2 Comments so far
hello sir !!!! i can call this article as Chemistry !!! Gasoline is better than fuel !!!
I’m wondering:
1) How much sawdust is needed per liter of gasoline? It sounds like roughly 1:1.
2) How many liters of sawdust/gasoline get made/used each year?
3) How hard would it be to use bulk cellulose (wood, hay) instead of sawdust?