Related Experiment Video
Updated: Sep 13, 2025
07:38
Characterization of Biological Absorption Spectra Spanning the Visible to the Short-Wave Infrared
Published on: January 10, 2025
1.6K
A universal model to predict DOC removal by coagulation based on UV-Visible absorption spectrum.
Yang Deng1, Hanzhe Wang1, Lei Zheng2
1Department of Environmental Engineering, Peking University, The Key Laboratory of Water and Sediment Sciences, Ministry of Education, Beijing, 100871, China.
Water Research
|July 29, 2025
Summary
Predicting dissolved organic matter (DOM) removal in drinking water treatment is challenging. This study shows a new method using UV-Vis spectroscopy to accurately predict DOM removal by coagulation, improving water treatment plant efficiency.
Area of Science:
- Water treatment technologies
- Environmental chemistry
- Spectroscopic analysis
Background:
- Dissolved organic matter (DOM) in drinking water reacts with disinfectants to form harmful disinfection byproducts (DBPs).
- Effective DOM removal is critical for safe drinking water, but predicting coagulation performance is difficult due to varying water sources and seasonal conditions.
- Current methods lack online characterization of DOM reactivity, hindering intelligent control in drinking water treatment plants (DWTPs).
Purpose of the Study:
- To develop a predictive model for dissolved organic carbon (DOC) removal during coagulation.
- To establish a link between DOM properties measurable by UV-Vis spectroscopy and coagulation efficiency.
- To enable intelligent control and optimize coagulation processes in DWTPs.
Main Methods:
- Analysis of DOC removal variations based on maximum removable DOC (DOCmax), alkalinity, coagulant type, and dosage.
- Characterization of DOM using Ultraviolet-Visible (UV-Vis) absorbance spectra.
- Deconvolution of UV-Vis spectra to identify absorbance Band A3 and its correlation with DOCmax.
Main Results:
- DOC removal is primarily determined by DOCmax, source water alkalinity, and coagulant parameters.
- A strong correlation (R² = 0.84) was found between DOCmax and the properties of absorbance Band A3 in the UV-Vis spectra.
- A universal model accurately predicts DOC removal using UV-Vis spectra across diverse water conditions (R² = 0.93).
Conclusions:
- Absorbance Band A3, identifiable via UV-Vis spectroscopy, serves as a key indicator for predicting DOCmax.
- The developed universal model enables accurate prediction of coagulation performance for DOC removal.
- These findings facilitate the development of smart dosing systems for enhanced coagulation control in DWTPs.
Related Concept Videos
01:14UV–Vis Spectrometers
1.5K
The absorbance of UV and visible (UV–visible) radiations is measured using a UV–visible spectrophotometer. Deuterium lamps, which emit UV radiation, and tungsten lamps, which produce radiation in the visible region, are used as light sources in UV–visible spectrophotometers. A monochromator or prism is used for diffraction grating, i.e., to split the incoming radiation into different wavelengths. A system of slits is used to focus the desired wavelength on the sample cell.
1.5K
01:02Ultraviolet and Visible (UV–Vis) Spectroscopy: Overview
3.1K
Ultraviolet–visible (UV–visible or UV–Vis) spectroscopy is an analytical technique that investigates the interaction between matter and UV–Vis light within the electromagnetic spectrum. This method is widely used for its versatility, simplicity, and relatively quick data acquisition, making it valuable for both qualitative and quantitative analysis. When UV–Vis radiation passes through a material, molecules absorb light depending on the energy required for...
3.1K
01:29UV–Vis Spectroscopy: Woodward–Fieser Rules
25.5K
UV–Visible absorption spectra of conjugated dienes arise from the lowest energy π → π* transitions. The light-absorbing part of the molecule is called the chromophore, and the substituents directly attached to the chromophore are called auxochromes. A strong correlation exists between the absorption maxima, λmax, and the structure of a conjugated π system. The Woodward–Fieser rules predict the value of λmax for a given...
25.5K
01:30UV–Vis Spectrum
1.3K
When light passes through a substance, a portion of the light is absorbed while the remaining light is reflected or transmitted. If the molecule absorbs light between the wavelengths of 180–400 nm range, the UV spectrum is obtained, and if it absorbs light in the 400–780 nm wavelength range, the visible spectrum is obtained.
The UV–Vis spectrum of a molecule is the plot of its absorbance versus wavelength. The plot is drawn by taking molar...
The UV–Vis spectrum of a molecule is the plot of its absorbance versus wavelength. The plot is drawn by taking molar...
1.3K
01:09UV–Vis Spectroscopy: Beer–Lambert Law
4.1K
The Beer-Lambert law describes the relationship between absorbance and concentration, which combines the principles established by scientists Johann Heinrich Lambert and August Beer. Lambert's law states that when light passes through a medium, the loss in intensity is directly proportional to the original intensity and the path length of the light. Beer's law proposed that the transmittance of a solution remains constant if the product of concentration and path length is constant. The...
4.1K
01:32UV–Vis Spectroscopy of Conjugated Systems
7.3K
Organic compounds with conjugated double bonds show strong absorption features in the UV–visible region of the electromagnetic spectrum attributed to π → π* electronic excitations. Generally, a UV–vis absorption spectrum is recorded as a plot of absorbance vs wavelength. The wavelength of maximum absorbance, which manifests as a peak in the absorption spectrum, is denoted as λmax.
One of the factors influencing λmax is the extent...
One of the factors influencing λmax is the extent...
7.3K