We have shown that mild heating of catechol SOA causes efficient acetone and CO2 production resulting from the decomposition of SOA compounds. The production of acetone and CO2 during heating coupled with the high viscosity of the catechol SOA have implications for extracting the volatilities of SOA components from thermograms. The production of acetone and CO2 implies fragmentation reactions of SOA components when heating, which will need to be considered when analyzing thermograms of catechol SOA and potentially other SOA materials where similar reactions and processes can occur.