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Levoglucosenone (LGO) has been known in scientific literature for some time although a route to obtain it at scale has only recently been demonstrated. It is of high interest as it can be produced directly from cellulose, the most abundant constituent of biomass and therefore a low cost feedstock. There are a number of points of chemical functionality with which to further react, the alkene, ketone and the acetal bridge as well as being produced in a single stereoisomer. This results in LGO having potential applications in the area of pharmaceuticals as well as a general platform molecule. Of most current interest is the ability to form the polar aprotic solvent dihydrolevoglucosenone, more formally known as Cyrene, via hydrogenation of the double bond.

Although there is some work looking at free sugars and reduced sugars in the synthesis of LGO, these show little enhanced benefit as compared to cheaper and more readily available feedstocks. The majority of papers and patents over the last 40 years have all used various lignocellulosic feedstocks, predominantly wood pulp or sawdust, as well as other cellulose-rich materials such as straws and grasses and also pure cellulose. A more recent and potentially very promising route to LGO utilises the “carbohydrate contaminated” lignin produced via second generation fermentation, in its self a significant and growing sector of the bio-economy producing predominantly ethanol, butanol and acetone without being part of the food versus fuel debate. Here the lignin byproduct still contains a significant portion of unfermented polysaccharides, which can be readily converted to LGO at a high yield and purity. This would be implemented in a bio-refinery concept, making a high value product from a low value side stream, while also producing a cleaner lignin by-product.

The 50 ton p.a. plant currently in operation is not primarily being used to supply LGO to market, but instead hydrogenates the platform molecule to give dihydrolevoglucosenone, more commonly known as Cyrene. Cyrene has generated interest as initial work on this molecule suggests that as a solvent it has similar properties to the key industrial polar aprotic NMP. This is significant as NMP has an annul production of 150,000 tons but has also recently been restricted by REACH and may move to full authorisation, meaning alternatives will be needed. However currently there are very limited alternatives, meaning a significant opportunity for Cyrene. To date Cyrene has been successfully applied in; exfoliation of graphene, pharmaceutically relevant carbon-carbon coupling reactions and the polymerisation and application of polyamide imides, all of which are currently conducted in NMP. Most importantly , Cyrene has received Annex VIII REACH approval and so can currently be manufactured or imported into the EU at up to 100 tons per annum.