Kinetic and thermodynamic comparative study of quince bio-waste slow pyrolysis before and after sustainable recovery of pectin compounds

RODRIGO TORRES SCIANCALEPORE; ANABEL FERNANDEZ BRIZUELA; DANIELA A. ASENSIO; MATHIAS RIVEROS ; MARÍA PAULA FABANI; GASTÓN FOUGA; ROSA RODRÍGUEZ; GERMÁN MAZZA

ENERGY CONSERVATION AND MANAGEMENT

PERGAMON-ELSEVIER SCIENCE LTD

Lugar: Amsterdam; Año: 2022 vol. 252 p. 1 - 14

0196-8904

This work aims to study and compare the kineticand thermodynamic behavior of pyrolysis of quince waste (QW) and pectin-freequince waste (PFQW) after extraction. The pectin extraction with acid treatmenthad a yield of 3.2 ± 0.1 %(dry basis, db). Pyrolysis was conducted in a macro-TG reactor at three heatingrates (5, 10, and 15 °C/min) and temperatures in the range 270-900 °C under a nitrogenatmosphere. A better fit of the experimental data was achieved bymodeling the reactions by a multi-step mechanism considering three differentparallel reactions for thermal decomposition of hemicelluloses, cellulose, andlignin. The results indicated that the Flynn-Wall-Ozawa (FWO) methodprovided the best R2, MSE, and AAD values. The resulting values of thethermodynamic activation parameters ΔH, ΔG, and ΔS were 53.28 ?89.36 kJ/mol, 114.54 ? 155.01 kJ/mol, and -0.17 ? (-0.04) kJ/(mol K) forpyrolysis of QW, and 29.97 ? 90.68 kJ/mol, 99.42 ? 158.86 kJ/mol, and -0.23 ?(-0.01) kJ/(mol K) for PFQW. According to bioenergy indicators, PFQW presentedgood characteristics as a biofuel feedstock due to its high energy densityvalues. The kinetic and thermodynamic parameters indicated greater reactivityof PFQW to pyrolysis compared to QW, showing that in addition to obtaining aproduct with added value, such as pectin, the extraction process generates asolid residue that is easier to treat under a thermochemical platform. Thenovelty of the paper focuses on the influence of the pretreatment of quincebio-waste (by extracting pectin compounds) on reactivity to pyrolysis,providing valuable kinetic and thermodynamic information.