Characterization of Humic Acid from the River Bottom Sediments of Burigonga: Complexation Studies of Metals with Humic Acid

In order to characterize and study of the complexation of humic acid with metal ions, sediment samples were collected from five different places in the Buriganga River. The Humic Acids were extracted with the standard procedure provided by the International Humic Substance Society (IHSS). The extracted Humic Acids were characterized with FTIR, EDX and CHNS analyzer and a comparison between the standard and extracted HA was carried out. High C/N ratios (71.48-87.36) are observed in the CHNS analysis. A complexation study of the Humic Acid with iron (III) and cadmium (II) was also carried out using EDX, UV-Visible spectrophotometer and AAS techniques. The coagulation behavior was observed with Jar test. From the study, it was found that iron and cadmium could make a complex at pH 6.0 which was confirmed by EDX (Electron Dispersive x-ray).