Co-pyrolysis of petroleum coke and wood pellet blend: Kinetic and Thermodynamic Evaluation using Thermogravimetric Analysis

Abstract

The increasing demand for sustainable energy attracted researchers to explore the co-pyrolysis of several wastes. The present study evaluated the kinetic and thermodynamic parameters for the co-pyrolysis of wood pellets and petroleum coke (1:1 by mass) blends using thermogravimetric analysis. The TGA data were analyzed through iso-conversional Ozawa-Flynn-Wall (OFW), Kissinger-Akahira-Sunose (KAS) models, along with the Coats-Redfern method. The results reflect that the order of reaction increases with an increased heating rate. An average value of activation energy calculated was 119.6 kJ mol−1 (OFW) and 126.2 kJ mol−1 (KAS). The values calculated for ΔH, ΔG and ΔS were in line with the past relevant studies on blends. The value ΔG was observed to fall around 182 kJ mol−1. The Coats-Redfern reaction mechanism indicates that D5 (based on diffusion) and F3 (based on chemical reaction) are best apt to the thermal process of degradation. DTA data specifies that degradation involves exothermic and endothermic reactions for the temperature range under study. The study not only provide the basic characteristics of one of the most dominant waste from refinery, but provides a platform for its futuristic potential usage with reliable kinetic and thermodynamic parameters for scale up, optimization, utilization and limitation for efficient system design.