Extraction of Fulvic Acid from Lignite and Characterization of Its Functional Groups
Guanqun Gong, Liangwei Xu, Yingjie Zhang, Weixin Liu, Ming Wang, Yufeng Zhao, Xin Yuan, Yajun Li
Abstract
oxidation of lignite, the content of -COOH increased, long-chain aliphatic compounds decreased, stretching vibrations of aromatic ring skeletons disappeared, and aromatic ring substitution became mainly tri- or disubstitution. Fluorescence spectroscopy indicated that FA had a low degree of aromaticity. X-ray photoelectron spectroscopy qualitatively and quantitatively revealed that the main modes of carbon-oxygen bonding in FA were C-O-, COO-, and C=O. Thus, this study not only lays a foundation for studying the composition and structure of coal-based FA but also opens a new avenue for a clean and efficient utilization of lignite.
Topics & Concepts
ChemistryAromaticityExtraction (chemistry)PyrolysisFourier transform infrared spectroscopyYield (engineering)Thermogravimetric analysisInfrared spectroscopyPeroxideCarbon fibersX-ray photoelectron spectroscopyComposition (language)Ring (chemistry)CoalMoleculeHydrogen peroxideOrganic chemistryChemical engineeringMaterials scienceComposite materialLinguisticsEngineeringComposite numberPhilosophyMetallurgyPlant Growth Enhancement TechniquesCoal and Its By-productsHumic Substances and Bio-Organic Studies