Pyrolysis of coffee residues, tobacco, and algae biomasses as a source of nitrogen-containing compounds

Abstract

Agro-industrial residues hold immense potential as sustainable energy and bioproduct sources. Thermoconversion through pyrolysis, which generates bio-oil, is a promising approach that simultaneously reduces environmental impact and adds value to biomass. Notably, biomasses with high nitrogen content yield bio-oils rich in diverse, industrially valuable nitrogen-containing compounds (N-compounds). This study investigates the rapid pyrolysis of five such biomasses: spent coffee grounds (SCG), silverskin (SVK), microalgae (MIA), macroalgae (MAA), and tobacco (TBC). A pretreatment step was employed to reduce fat content and enhance bio-oil quality. Gas chromatography analysis subsequently identified the generated N-compounds. The bio-oils revealed a significant presence of oxygenated compounds and hydrocarbons beside N-compounds. The use of Principal Component Analysis (PCA) effectively allowed to group the samples based on their bio-oil compositions, highlighting microalgae as the richest source of N-compounds, particularly after fat pre-extraction.

HIGHLIGHTS

• Fast pyrolysis of protein-rich biomasses yields valuable bio-oils with oxygenated compounds, hydrocarbons, and nitrogen containing compounds.

• Identified compounds offer potential applications in chemical, pharmaceutical, and related industries.

• Study demonstrates biomass’s promise as a sustainable source of energy and bioproducts.

• Fast pyrolysis proves viable for converting biomasses into valuable bio-oil products.

• Results highlight biomass’s significance in environmentally friendly and value-added processes.

Keywords:

• Pyrolysis
• bio-oil
• biomass
• EDGE extraction
• N-compounds
• GC/TOFMS

Acknowledgments

The authors thank CAPES and CNPq for the scholarships awarded to support this study and PETROBRAS for providing the necessary financial support for the project.

CRediT authorship contribution statement

• Conceptualization: Prof. Dr. E. B. Caramão, Prof. Dr. T. R. Bjerk, Dr. J. K. Schneider, Dr. A. L. dos Santos, Dr. L. S. Freitas,

• Investigation, analysis, and data interpretation: MSc. A.N.L. Lucas, Dr. A. L. dos Santos, Dr. A. S. Polidoro, MSc. I.D.P. da Mota, Dr. R.O. Farrapeira, Dr. Y.B. Andrade.

• Writing original draft, writing-review, and editing: MSc. A.N.L. Lucas, MSc I.D.P. da Mota, Dr. R.O. Farrapeira, Dr. Y.B. Andrade, Dr. A. S. Polidoro, Dr. E. B. Caramão.

• Resources, Funding acquisition, and Project administration: Prof. E. B. Caramão, Dr. T.R. Bjerk.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Data availability statement

Data will be made available on request.