Pyrolysis of corn bioethanol by-products: Comprehensive chemical characterization of bio-oil and optimization of the liquid yield

Abstract

Pyrolysis is a versatile technology that contributes to minimizing global warming risks and applied to agro-industrial residues can develop alternative energy sources, guaranteeing universal access to affordable, safe, sustainable and modern energy. Thermal pyrolysis of corn bioethanol industry by-products, Dried Distilled Grains with Soluble and parameter conditioning were studied using a laboratory scale reactor system to optimize the bio-oil yield. The Dried Distilled Grains with Soluble and bio-oil obtained have been extensively characterized through different analytical techniques. The results show that the bio-oil yield was the largest at 550 °C temperature reaction, with a flow rate of 50 mL min−1 of N2 and 10 min. Among the liquids, two phases barely reported, were distinguished and thoroughly analyzed by gas chromatography–mass spectrometry technique. This study identified a clear phase, primarily composed of alcohols, organic acids, low molecular weight compounds and water, and a dark phase, rich in phenols, organic acids, aliphatic and aromatic hydrocarbons. Dark phase exhibited a high calorific value of 29.52 MJ/kg, positioning it as a promising candidate for biofuel applications. These findings provide new insights into composition and potential uses of bio-oil and highlight the feasibility of valorizing corn bioethanol industry by-products into high-value bio-chemical platforms and renewable energy.