Identification, Extraction, And Purification Of High Value Chemicals In Biomass

The CBE-JU recognises that biomass valorisation can involve much more than the processing of cellulose, hemicellulose, and lignin. Non-structural components of the plant can also be of value, in some cases being worth thousands of Euros per kilogramme. There are numerous examples of such high value constituents, with the most prominent recent example being the extraction, isolation, and purification of cannabinoids (in particular CBD and CBG) from hemp, which has developed into a multi-billion Euro industry.

At Celignis, we can play important roles at all stages in the valorisation of such compounds, starting from their identification and ending in their purification and the testing and modification of their functional and chemical properties. For identification, we firstly get a crude extract from the feedstock, obtained via various approaches, including pressurised liquid extraction. This extract is then profiled using our top-range QTOF-LC/MS system (Agilent iFunnel 6550), which can identify constituents to the femtogram-level, and the spectra and chromatograms reviewed by Sajna, our Bioanalysis Developer. If necessary, we can collect the relevant fractions from the LC system and confirm the identification using a number of different chemical and spectroscopic techniques. We then determine which constituents warrant extraction and then work on optimising a targeted extraction method. This method considers not only the yield of the target compound(s) but also the chemical and energy costs of the process and the implications for the downstream processing and valorisation of the solid residue, evaluated by Oscar, our technoeconomics analysis (TEA) expert. We subsequently work on the isolation and purification of the targeted compound(s) from this extract, again considering the commercial and scale-up implications.

Celignis undertook such an approach in the CBE/BBI project UNRAVEL where the extractives of 25 feedstocks were profiled using QTOF-LC/MS. We identified betulin in birch bark as the most attractive compound and subsequently worked on developing an optimised extraction protocol and an isolation/purification process scheme that offered several advantages, in terms of sustainability and safety, over the current art. Click here for a news article on this work. We are also using employing our compositional analysis and purification expertise in the Horizon Europe project SteamBioAfrica where we evaluate and process the liquid condensate obtained from the steam torrefaction process and consider market applications for its constituents, fractions, and derivatives.

Our high-value-chemicals expertise is of particular value for improving the competitiveness of a biorefinery process, through employing the principle of the cascading use of biomass. For example, a relatively minor component of biomass can substantially improve the financial viability of a technology if it can be sold at a high price. As a result, such an approach can make important contributions to a number of the 2022 topics, such as: JU-CBE-2022-R-05 (Sustainable fibres biorefineries feedstock), JU-CBE-2022-IA-04 (Co-processing of mixed bio-based waste streams), JU-CBE-2022-IA-02 (Cooperative business models for sustainable mobilisation And valorisation of agricultural residues, by-products, and waste in rural areas), and JU-CBE-2022-IAFlag-01 (Maximum valorisation of sustainably sourced bio-based feedstock in multi-product, zero-waste, zero-pollution biorefinery).