Pyrolysis of Coconut Inflorescence Wastes: Production, Effects of Parameters, Characterization and Optimization of Phenolic-Rich Bio-Oil

The coconut industry has great economic importance for the Asia–Pacific region and Brazil. For this reason, researchers have given special attention to coconut shells and fibers as fuel sources. However, other residues as coconut inflorescence wastes (CIW) have been neglected. In this work, CIW were pyrolyzed. Effects of pyrolysis temperature (290–710 °C) and heating rate (2–58 °C∙min −1 ) were evaluated. A full factorial design (FFD) was developed to identify interaction effects. Product (biochar, gas and bio-oil) yield and phenol concentration in the bio-oil ( C_Phenol ) were the responses investigated. Response surface methodology and central composite design (CCD) were used to obtain optimum conditions. Biomass and bio-oil were further characterized by thermogravimetric (TG) and GC–MS analyses. TG results indicated the FFD levels. Temperature and heating rate showed significant effects on the responses. A linear model was suitable for gas yield, while quadratic models were fitted to other responses. A trade-off analysis between bio-oil yield and C_Phenol detected optimum values of 42.9