<p>Lignocellulosic biomass (LC) is a non-food-competing resource that can be converted into valuable products via pyrolysis. However, its complex polymeric structure makes this process challenging. Acetylation is a promising chemical treatment to enhance the efficiency of biomass pyrolysis. Furthermore, thermogravimetric analysis (TG) is a simple and low-cost technique that can be used to simulate pyrolysis, although dynamic TG curves may not be appropriate for LC. This work investigated the effects of acetylation on the chemical composition, thermal behavior, and catalytic thermo-degradation of three types of LC (wood sawdust, coconut husk, and cow manure). Acetylation was performed using acetic anhydride and sulfuric acid under microwave irradiation, and catalytic thermo-degradation was investigated by dynamic and isothermal TG analysis. Acetylation enhanced carbon content and total mass loss while decreasing residual mass in all biomass types. Interestingly, isothermal TG analysis revealed improved interaction between the catalyst and LC, surpassing dynamic analysis in catalytic thermo-degradation. Remarkably, the isothermal TG analysis showed greater mass loss in the presence of the catalyst. The combined effect of acetylation and the catalyst increased biomass thermo-degradation by 4.5% at 523&#xa0;K compared to raw biomass. This suggests that acetylation combined with catalytic thermo-degradation can enhance the pyrolytic conversion of lignocellulosic biomass, with efficiency evaluated through isothermal TG analysis.</p> Graphical abstract <p></p>