The present invention provides improved process for the sulfonation of hydroxyaromatics amenable to direct isolation of the sulfonylated hydroxyaromatics in their free-acid forms. The process allows for the recyclization of sulfuric acid and minimizes waste. The starting materials are from a renewal resource, e.g., biomass, and contain detectable 14C up to a 14C content of 0.0000000001% (one part per trillion). The products made include sulfonated catechol, disulfonated pyrogallol and sulfonated protocatechuic acid.