Application of surrogate parameters in characteristic UV–vis absorption bands for rapid analysis of water contaminants

Abstract

In recent years, absorption spectroscopy is being widely used for water quality monitoring. However, much of the spectral analysis results do not provide any physical meaning and the use of traditional parameters for monitoring water quality, such as chemical oxygen demand (COD), is not a radical research method because of the large diversity of chemical components in water. Here in, we studied the absorption spectra of eight typical contaminants and proposed four integral parameters in different spectral ranges, which were relative to different functional groups. The proposed surrogate parameters can be used to rapidly analyze and predict the categories of contaminants based on their changes without using any modeling. We used a dynamic partitioning algorithm based on the fourth-order derivative spectrum to adapt the movement of absorption bands. The impact of turbidity was eliminated by deducting the turbidity component from surrogate parameters based on the proportion of four parameters in formazine turbid solution. Using this method, we conducted long-term monitoring of the wastewater released by a dyeing and printing plant. The rapid analysis and prediction potential of different categories of water contaminants was demonstrated. The prediction results can provide evidence for more targeted and detailed analysis and water quality monitoring.