Study of Spectral, Structural and Chemical characteristics of Humic Acids Isolated from Coalfield of Iran

Due to substantial impact of humic substances on a variety of environmental processes, knowledge of the chemical, spectroscopic and structural properties of these substances, are aspects that should always be considered in studies related to the management and remediation of impacted ecosystems. In this study, after from extraction and purification of humic acid (HA) from low grade coals of IRAN, was used from gravimetric technic in order to determination of degree of purity of HA, from non-destructive spectroscopies such as ICP-OES, UV-VIS, FT-IR and CHNOS for measuring of quality and quantity of HA as well as from microstructures of SEM in order to structural study of HA and obtained results were compared with standard Aldrich HA. Results of gravimetric analysis showed that degree of purification of produced HA is 98%. Also, In point of quantity, results of elemental analysis of ICP-OES showed that after from purification of HA, the concentration of various heavy metals in HA are lower from recommended safe limit and there have macro and micronutrients at ranges in HA structure. Also, quality results of FT-IR, UV-VIS and SEM analysis, shown well presence of an aromatic predominant structure and rich from carboxylic and phenolic functional groups with high humification and condensation degree and A type with a loose spongy and heterogeneous porous surfaces for HA. CHNOS analysis also confirmed the suitability of the coal used to extract HA, and showed that the final product is in accordance with the standard HA results.