Characterization of anthropogenic organic matter and its interaction with direct yellow 27 in wastewater: Experimental results and perspectives of resource recovery

The concept of natural organic matter of anthropogenic origin is introduced and its characteristics and interaction with chemical pollutants are investigated by adopting several distinct analytic methodologies. Scanning electron microscopy indicates that the used sample of anthropogenic organic matter (AOM) has an amphiphilic nature, which allows its supramolecular organization in water. Fourier transform infrared spectroscopy, in turn, gives a clear indication about the presence of polysaccharide markers, lipidic and amidic fractions, and suggests the absence of free organic acid. AOM sample and AOM mixed with dye sample were examined by the three-dimensional excitation-emission matrix fluorescence spectra and the nuclear magnetic resonance mono-dimensional spectra. The results highlighted the interactions occurring between the AOM and the reactive dye, selected as a representative chemical pollutant. Electron Spin Resonance confirms that the used AOM is able to completely include the dye in its structure. Overall, the obtained results indicate that the fate, transport, and toxicity of pollutants in the environment can be drastically influenced by the presence of AOM.