Modeling the behavior of Celtis mildbraedii sawdust and polyethylene terephthalate co-pyrolysis for syngas production

The co-pyrolysis behavior of Celtis mildbraedii sawdust (CMS) and polyethylene terephtha-late (PET) waste for syngas production was investigated using a response surface method-ology (RSM) based on Box-Behnken design (BBD). The production parameters were exam-ined at a temperature, feedstock concentration (CMS/PET ratio), and nitrogen (N 2 ) gas flow rate range of 60 0-80 0 degrees C, 50/50-80/20%, and 2-10 normal liters per minute (NL/min), re-spectively. A second-order regression model was used to predict the response with the outcomes analyzed using Minitab statistical software (version 19) at a 95% confidence in-terval. Results showed that CMS can be used solely and/or in a mixture with PET for pyrol-ysis. The syngas yield was influenced by the interactive effects of temperature and N 2 gas flow rate with a significant p-value of less than 0.05. It was observed that temperature was the most influencing factor due to its high F-value of 355.06. The optimum yield of syn-gas was attained at a temperature of 800 degrees C, N 2 gas flow rate of 6 NL/min, and feedstock concentration of a mixture of 50 wt.% of sawdust and 50 wt.% of plastic. At these con-ditions, the obtained syngas yield was 68.1 wt.%. In conclusion, the current study proves that co-pyrolysis has the potential to convert biomass and plastics to fuels and other green chemicals.(c) 2022 The Authors. Published by Elsevier B.V. on behalf of African Institute of Mathematical Sciences / Next Einstein Initiative. This is an open access article under the CC BY license ( http://creativecommons.org/licenses/by/4.0/ )