(197b) Non-Thermal, Atmospheric Plasma Conversions of Biomass into Value-Added Chemicals: Solvent-Plasma Based Conversion

Non-thermal, atmospheric pressure plasma can be a new promising method to convert biomass into biofuels and chemicals. When high-voltage electricity is applied to dielectric materials, chemically rich environment containing ions, radicals, atoms, and electrons are formed. These reactive species can interact with biomass to promote various reactions, and thus conversion could occur at low-energy costs. Previously, we have increased levoglucosan yield during cellulose pyrolysis from 58% to 78% by plasma-pretreating cellulose for 30s. In the present study, solvent-plasma conversion of biomass is further studied. It is known that polar aprotic solvent can convert cellulose into important biochemicals. We found that introducing plasma into room-temperature solvents during cellulose conversion not only can greatly shorten the conversion time, but also achieve high conversion and product selectivity. For example, in the plasma-treated gamma-Valerolactone (GVL), the Levoglucosenone (LGO) yield from cellulose reached 24.2wt% within 5 minutes in the presence of 7mM H₂SO₄ and it further increased to 33.7wt% after 15 minutes. In comparison, LGO yield was only up to 8.4wt% in conventional batch reactors maintained at 200℃ even after prolong heating time. We also found that the effect of solvent-plasma is highly dependent on the choice of solvent. In sulfolane, not only LGO is produced, but GVL was also found among the products, indicating in-situ hydrogenation occurs.