Methods are disclosed for producing, from renewable carbon sources, acetic acid in an economical manner. In particular, these methods are directed to the separation and recovery of acetic acid as a substantial product (e.g., as much as 5% by weight or more) of biomass pyrolysis. For a given commercial biomass pyrolysis unit, the acetic acid yield can represent a significant quantity of that used in a major industrial applications such as purified terephthalic acid (PTA) production. According to some embodiments, pyrolysis conditions and/or flow schemes advantageously improve the recovery of acetic acid for a given purity level.