Investigation of the Structural Features and Interactions of Aquatic Fulvic Acids in Surface and Groundwater

摘要

Structural features and interactions of aquatic fulvic acids (FA) were investigated by combined chromatographic and spectroscopic techniques. Analytical and preparative reversed-phase liquid chromatography were used to separate constituents of FA. A catalog of the uv-vis scans of FA constituents were developed using RP-HPLC under different mobile phases and gradient programs. The overall results indicate that: FA macromolecules consist of a molecular complex which can be separated into three to six subunits; Each subunit may contain two or three structurally related compounds; vanillic acid, conjugated ketones and phenols represent the backbone structures in FA; the free radical in FA regulates the transformations of 1,2,4,5,TCB in aqueous solution but does not influence its aqueous solubility; at least four binding sites in FA participate in complexation with Cu2+. The first available sites are those participating in square planar complexes.