(444b) Purification of Lignin Monomers from Poplar Derived Reductive Catalytic Fractionation Oils with Counter-Current Chromatography

Reductive Catalytic Fractionation (RCF) is an emerging “lignin first” biomass pretreatment technique that produces a soluble stream of lignin compounds at appreciable concentrations. Direct isolation of these lignin compounds can yield high value co-products within a biorefinery. However, the isolation of individual compounds from RCF oil is challenging due to the inherent chemical complexity of the oil. For example, the use of traditional Simulated Moving Bed (SMB) technology for direct product isolation is problematic because dimers, trimers, and higher order partially depolymerized lignin present in the oil rapidly fouls the stationary phase. Thus, extensive upfront filtration, down to the nanofiltration level, is needed before SMB can be used. This filtration significantly lowers product yields (> 50%) and is not practical. One novel approach is to use Counter-Current Chromatography (CCC) to separate lignin monomers from RCF oil. CCC is promising process to recover bioproducts from these complex streams because it employs two liquid phases for both the mobile and stationary phase and therefore does not require a solid liquid (S/L) separation upfront. This is a form of process intensification, where the S/L separation occurs within the CCC device and is not required upfront as opposed to traditionally employed SMB. In this presentation, CCC will be discussed for separating bioproducts and biochemicals from RCF oils. Based on the experimental data, an economic analysis of the separation and recovery process will be presented and compared with processes using other state-of-art technologies including SMB.