Nanoporous Materials for Selective Separation and Purification of Phenolic Oligomers from Lignin-First Biomass Processing (RPA Pilot / Seed Project)

In this project, superficially porous silica microspheres (SPSMs) are synthesized, characterized, and functionalized with macrocyclic host sites for selective separation of low molecular weight phenolic derivatives from lignin-first processing of lignocellulosic biomass. Lignin-derived phenolics are high-value precursors to therapeutics, chemicals, and materials that can be sustainably manufactured from agricultural and forestry residues produced in Kentucky. SPSMs are proposed as high-performance adsorbents and chromatographic packing material amenable to fluid flow because they balance the high surface area of a superficial layer of nanopores hundreds of nanometers thick with a solid core that provides mechanical strength and micron-scale particle size. By adding -CD (a ring of 8 glucose molecules that forms inclusion complexes) functionality to the pore surface, the proposing team hypothesizes that the materials will be selective for phenolics with two methoxy substituents such as syringaresinol, a high value therapeutic found in agricultural residues from wood. The proposed work will advance the team’s understanding of the relationship between synthesis variables, nanopore layer dimensions, and effectiveness as materials for separation platform development. These advanced materials will be foundational to low-energy separation processes (e.g. adsorption) for phenolic derivatives from the lignin biopolymer found in plant biomass. The fundamental insights into binding behavior of phenolics to nanopore-confined CDs will facilitate the development of membranes for scaleup and process development.