Towards cleaner downstream processing of biomass waste chemical products by liquid chromatography: A review and recommendations

Activity in the area of biomass waste valorization had focused on upstream processes that enabled access to target compounds (i.e., complex carbohydrates, lignins, lipids, and proteins) from biomass waste. There had been less activity in the downstream processes that typically incorporate separation steps to deliver commercial products that satisfy chemical specifications. Tougher specifications (e.g., for human use) require a greater number of purification steps. Downstream processing involves complex procedures. Thus, is easily the most expensive stage in product development. In this review, a critical evaluation of liquid chromatographic methods as purification approaches for downstream processing of biomass waste derived chemicals was done. The methods were also discussed within the context of green chemistry to encourage cleaner production. An overview of the relevant liquid chromatographic techniques is provided for novice researchers. Majority of the research is still in the laboratory scale. We expect the activity in liquid chromatography for downstream processing to increase once viable upstream valorization approaches move closer from the laboratory scale and into a commodity-driven scale. Research on the development of less toxic solvent systems and/or innovative separation media for faster and efficient liquid chromatography approaches are encouraged.