Abstract: Various embodiments of microwave-assisted systems, devices, and associated methods of operation are described herein. In one embodiment, a method for producing a bio-oil from a carbonaceous material includes feeding the carbonaceous material to a pyrolysis reactor, pyrolyzing the carbonaceous material in the reactor to produce a raw bio-oil containing oxidized aromatic hydrocarbons, and catalytically reducing at least a portion of the oxidized aromatic hydrocarbons in the raw bio-oil to produce an upgraded bio-oil having reduced aromatic hydrocarbons.