Pyrolytic Characterization of Marine Algae Solieria filiformis as Renewable Energy Source and Its Effect on Gas Emission Profile during Co-pyrolysis with Waste PVC

Abstract

Non-isothermal kinetic assessment of seaweed biomass (e.g., Solieria filiformis) was studied using three different iso-conversional kinetic methods to calculate activation energy. S. filiformis biomass decomposed in three stages: Zone I (300–457 K), Zone II (458–845 K), and Zone III (846–1150 K), respectively. Average activation energies for Zone I, Zone II, and Zone III were observed in the ranges of 73–77, 281–366, and 441–448 kJ/mol with Kissinger–Akahira–Sunose (KAS), Flynn–Wall–Ozawa (FWO), and Starink methods, respectively. In this study, three blends of S. filiformis biomass with poly(vinyl chloride) (PVC) waste in 30:70 w/w, 50:50 w/w, and 70:30 w/w were prepared and screened based on thermal decomposition temperature to understand the effect of co-pyrolysis. Co-pyrolysis has shifted the decomposition temperature of PVC from 572 to 560 K (12 K) in a 70:30 w/w (biomass/PVC) blend and found suitable for the co-pyrolysis. In this co-pyrolysis blend, mass fragments of hydrocarbons and volatile components of waste PVC were monitored by a thermogravimetric analysis-mass spectrometry (TGA-MS) instrument. Results of this study revealed that emission of hazardous (HCl, m/z = 36; benzene, m/z = 78) components was decreased significantly in the presence of biomass, while commercially important hydrogen (H₂) and methane (CH₄) gas evolution was enhanced.