Hydrochar obtained with by-products from the sugarcane industry: Molecular features and effects of extracts on maize seed germination

Author(s)

Bento, Lucas Raimundo ^{[1, 2]} ; Spaccini, Riccardo ^[2] ; Cangemi, Silvana ^[2] ; Mazzei, Pierluigi ^{[2, 3]} ; de Freitas, Bianca Borge ^[1] ; Oliveira de Souza, Andressa Eva ^[1] ; Moreira, Altair Benedito ^[1] ; Ferreira, Odair Pastor ^[4] ; Piccolo, Alessandro ^[2] ; Bisinoti, Marcia Cristina ^[1]

Affiliation

^[1] Univ Estadual Paulista, UNESP, Inst Biociencias Letras & Ciencias Exatas, Lab Estudos Ciencias Ambientais LEGA, Dept Quim &, Sao Jose Do Rio Preto, SP - Brazil

^[2] Univ Napoli Federico II, Ctr Interdipartimentale Ric Risonanza Magnet Nucl, Naples - Italy

^[3] Univ Salerno, Dipartimento Farm DIFARMA, I-84084 Fisciano, SA - Italy

^[4] Univ Fed Ceara, Dept Fis, Lab Mat Funcionais Avancados LaMFA, Fortaleza, Ceara - Brazil

• Document type: Journal article
• Source: Journal of Environmental Management; v. 281, MAR 1 2021.
• Web of Science Citations: 0

Abstract

Sugarcane bagasse, vinasse and a mixture of sugarcane bagasse and vinasse were hydrothermally carbonized (HTC), with and without the addition of phosphoric acid, in order to propose new applications of sucroenergetic industry by-products on soil. Detailed information on the composition and properties of hydrochars has been obtained through elemental composition, thermogravimetric analysis, nuclear magnetic resonance and, thermochemolysis GC-MS. The soluble acidic fraction from the hydrochar samples were applied to maize seeds to evaluate the agronomic potential as biostimulants and relate the molecular features with maize seed germination. The HTC treatment converted polysaccharide-based biomasses into hydrochars with hydrophobic characteristics (C-Aryl and C-Akyl). Furthermore, the addition of phosphoric acid further increased the overall hydrophobicity and shifted the thermal degradation of the hydrochars to higher temperatures. Biomass influenced the hydrochars that formed, in which the molecular features of sugarcane bagasse determined the formation of more polar hydrochar, due to the preservation of lignin and phenolic components. Meanwhile, the HTC of vinasse resulted in a more hydrophobic product with an enrichment of condensed and recalcitrant organic fractions. The germination assay showed that polar structures of bagasse may play a role in improving the maize seeds germination rate (increase of similar to 11%), while the hydrophobic domains showed negative effects. The responses obtained in germination seems to be related to the molecular characteristics that organic extracts can present in solution. (AU)

• FAPESP's process: 18/15733-7 - Evaluation of the use of hydrochar for agricultural purposes and of magnetic coal as adsorbent material
• Grantee: Márcia Cristina Bisinoti
• Support Opportunities: Program for Research on Bioenergy (BIOEN) - Regular Program Grants
• FAPESP's process: 17/17991-0 - Molecular characterization of the humic substances from "Terra Preta de Indio" soils and hydrochar from sugarcane wastes" by Humeomics
• Grantee: Lucas Raimundo Bento
• Support Opportunities: Scholarships abroad - Research Internship - Master's degree
• FAPESP's process: 17/05575-2 - Structural similarity of the humic substances from hydrochar obtained from vinasse and sugarcane bagasse with the Black Earth (TPI)
• Grantee: Lucas Raimundo Bento
• Support Opportunities: Scholarships in Brazil - Master