Co-Pyrolysis of Corn Stover with Plastic: Optimization Based on Synergy

The co-pyrolysis of lignocellulosic wastes such as Corn stover with plastic has been found to improve the both the yield and quality of pyrolysis oil and gas products. In this study, the co-pyrolysis of Corn stover (CS) with plastic (LDPE, and PP) were studied through thermogravimetric analysis. The parameter “change in weight loss rate” denoted by ΔW was used to quantify the synergistic effects on the yield during co-pyrolysis. The ΔW values were fitted using a combined mixture design to generate an RSM model relating the factors mixture component proportions, plastic type, and temperature to the response ΔW. From numerical optimization, the obtained optimum co-pyrolysis conditions are: (a) 0.60 CS proportion, 0.40 LDPE proportion, and 481.73 ℃ temperature for CS-LDPE, (b) 0.68 CS proportion, 0.32 PP proportion, and 492.15 ℃ temperature for CS-PP. The activation energy, and pre-exponential factor of the reactions in the co-pyrolysis process were also obtained using direct solution method. The activation energy of the reaction that took place from 420 to 510 ℃ was found to be lower in the co-pyrolysis of Corn stover and plastic than in the pyrolysis of pure plastic.