Influences of copper on the pyrolysis process of demineralized wood dust through thermogravimetric and Py–GC/MS analysis

• Thermogravimetric analysis to assess the effect of copper on wood dust pyrolysis.
• Py–GC/MS was employed to detect the components of pyrolytic compounds.
• Activation energy was calculated through model-free methods.
• An increase of 70–80 kJ/mol activation energy with copper impregnation.
• Thermogravimetric analysis was consistent with pyrolytic compounds detection.

Thermogravimetric analysis combined with an analytical pyrolyzer coupled with a gas chromatography–mass spectrometry set-up (Py–GC/MS) was employed to elaborate on the influences of copper on the demineralized wood dust pyrolysis process for the purpose of the proper disposal, through pyrolysis technology, of biomass contaminated by heavy metals. Demineralized wood dust was prepared through an acid-washing process with 0.1% nitric acid (AWD) and then impregnated with copper salt for Cu–AWD. The results showed great differentiations of thermogravimetric curves between the two samples, the most obvious being the decrease of the maximum mass loss temperature, from 391 °C to 276 °C at 30 °C/min, for example. The calculated activation energy, using the model-free Ozawa and Starink methods, exhibited an increase of 70–80 kJ/mol with copper impregnation at the conversion of 10–40% corresponding to the pyrolysis temperature of the main wood components hemicellulose and cellulose. Further investigations through the detection of the two samples’ pyrolytic products revealed that copper had a different influence on the pyrolysis process of the primary wood compositions, which was consistent with the calculated activation energy.