Kinetic study of the pyrolysis of pine cone shell through non-isothermal thermogravimetry: Effect of heavy metals incorporated by biosorption. (October 2016)

• Record Type: Journal Article
• Authors: Martín-Lara, M.A.; Blázquez, G.; Ronda, A.; Calero, M.
• Is Part Of: Renewable energy. Volume 96:Part A(2016)
• Page Start: 613
• Page End: 624
• Publication Date: 2016-10
• Subjects: Biosorption -- Heavy metals -- Kinetics -- Pine cone shell -- Pyrolysis -- Thermogravimetric analysis; Renewable energy sources -- Periodicals; Power resources -- Periodicals; Énergies renouvelables -- Périodiques; Ressources énergétiques -- Périodiques; 333.794
• DOI: 10.1016/j.renene.2016.05.026
• Languages: English
• ISSNs: 0960-1481

Abstract

Abstract: The study concerns the pyrolysis kinetics of exhausted pine cone shell after its use as biosorbent of copper and lead from aqueous solutions in a fixed bed column. First, breakthrough curves of biosorption process were obtained. Main dynamic biosorption parameters were determined and analyzed. Then, non-isothermal thermogravimetric experiments were carried out with raw and metal-loaded biomass in a thermobalance under nitrogen atmosphere at different heating rates. A comparative study was performed. The activation energy dependent on the conversion rate was estimated by Flynn–Wall–Ozawa (a free integral or iso-conventional method) and a mechanistic model (an integral or model-fitting method that considers three independent parallel reactions). The fluctuation of activation energy in Flynn-Wall Ozawa model can be considered the result of thermal degradation reactions of different pseudo-components of the lignocellulosic material (hemicellulose, cellulose and lignin). For raw pine cone shell and metal-loaded-pine cone shell, best fit parameters were determined according to a three independent parallel reactions scheme. The copper and lead present in metal-loaded samples did not modify values of determined parameters which describe the pyrolysis process. Finally, chemical analysis of the chars indicated that about 95% and 99% of copper and lead presented on original waste was recovered in generated chars. Highlights: Copper and lead biosorption onto pine cone shell was performed in a fixed-bed column. Pyrolysis kinetics of raw and metal-loaded samples was studied via non-isothermal TGA. Two models for the prediction of kinetics of pyrolysis were evaluated. Measured curves are well described by a three parallel reactions mechanistic model. Copper and lead in metal-loaded-PCS samples not modified pyrolysis kinetics.