Analysis of pyrolysis characteristics and kinetics of Euphausia superba shell waste using TG-FTIR and distributed activation energy model

Pyrolysis of Euphausia superba shell waste (ESW) was investigated by using a thermogravimetric analyzer coupled with a Fourier transform infrared spectrometer (TG-FTIR). The kinetic parameters of pyrolysis reactions were obtained via the distributed activation energy model (DAEM). Experimental results showed that the temperature at which the highest weight loss rate occurred increased from 280 to 315 °C as the heating rate increased from 5 to 30 °C min⁻¹. Almost all the volatiles were evolved between 300 and 350 °C, while CH₄ and aliphatic C–H were also produced at higher-temperature regions. A large amount of CO₂ was generated above 650 °C by the decomposition of carbonates, and it can be further reduced to CO by ESW char. CO₂ was the main non-condensable product, and ketones were the dominating condensable products. The activation energy of pyrolysis reactions increased from 79 to 392 kJ mol⁻¹ for conversion rates 0.13 to 0.54. The linear relationship between the natural logarithm of the frequency factor and activation energy was also established. The activation energy approximately followed Gaussian distribution, and the mean activation energy was 162 kJ mol⁻¹.