Continuous solvent liquefaction of biomass in a hydrocarbon solvent

- Solvent liquefaction process to convert southern yellow pine to liquids.
- Pilot-scale process development unit was developed to 1 kg/hr.
- Primary liquid product is a promising biorenewable petroleum blendstock.
- Continuous online bio-oil fractionation was achieved with 76% overheads.

Solvent liquefaction (SL) of biomass is a promising technology for the conversion of biomass to renewable fuels and chemicals. Liquid-phase thermal deconstruction of biomass in the presence of hydrocarbon-based hydrogen-donating solvents can result in bio-oils with low moisture and low oxygen content. These oils are thermally stable and highly miscible with hydrocarbon streams, which make them a promising biorenewable blendstock for petroleum refineries. We have developed a 1 kg hr−1 continuous SL pilot plant to evaluate the performance of SL of southern yellow pine in a hydrocarbon solvent. The process development unit (PDU) was also designed to evaluate several unit operations critical to large-scale operations. Online solids removal was conducted with inline wire mesh barrier filters with separation efficiency of over 99%. Acetone injection was used to aid in solids removal, and an online recovery system was demonstrated with greater than 97% acetone recovery. Continuous online bio-oil fractionation was also demonstrated using a distillation column to separate approximately 93 wt% of the initial solvent from the biomass-derived products.