Prediction of chlorination degradation rate of emerging contaminants based on machine learning models.

Journal: Environmental pollution (Barking, Essex : 1987)
PMID:

Abstract

Assessing the degradation of emerging contaminants in water through chlorination is crucial for regulatory monitoring of these contaminants. In this study, we developed a machine learning model to predict the apparent second-order reaction rate constants for organic pollutants undergoing chlorination. The model was trained using second-order reaction rate constants for 587 organic pollutants, with 314 data points obtained from actual experiments, the other data points 273 came from previous studies. We evaluated ten machine learning algorithms with Modred molecular descriptors and MACCS molecular fingerprints, optimizing the hyperparameters through Bayesian optimization to enhance the predictive capability of the model. The optimized model GPR algorithm combined with molecular fingerprint model achieved R = 0.866 and R = 0.801. Subsequently, the model was fed with chemical features of four organic pollutants, and the predicted results were compared with experimentally obtained values, the deviations between predicted and experimental values were found to be 2.12%, 0.37%, 0.15%, and 14.8%, respectively, further validating the accuracy of the predictive model. SHAP analysis showed that the amino-methyl group CN(C)C had the highest feature value, demonstrating the interpretability of the model in predicting chlorine-degraded pollutants The model established in this study is more representative of real chlorination environments, providing preliminary guidance for chlorination plants on the degradation of numerous emerging contaminants lacking treatment standards and facilitating the refinement of strategies for the prevention and control of emerging contaminants.

Authors

  • Yufan Du
    School of Environment and Energy, South China University of Technology, Guangzhou, 510006, China.
  • Ting Tang
    Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou 510642, China.
  • Dehao Song
    School of Environment and Energy, South China University of Technology, Guangzhou, 510006, China.
  • Rui Wang
    Department of Clinical Laboratory Medicine Center, Inner Mongolia Autonomous Region People's Hospital, Hohhot, Inner Mongolia, China.
  • He Liu
    Division of Endodontics, Department of Oral Biological and Medical Sciences, Faculty of Dentistry, University of British Columbia, Vancouver, BC, Canada.
  • Xiaodong Du
    College of Water Resources & Civil Engineering, China Agricultural University, Beijing 100083, China.
  • Zhi Dang
    School of Environment and Energy, South China University of Technology, Guangzhou, 510006, China; Guangdong Provincial Key Laboratory of Solid Wastes Pollution Control and Recycling, South China University of Technology, Guangzhou, 510006, China; The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, South China University of Technology, Guangzhou, 510006, China.
  • Guining Lu
    School of Environment and Energy, South China University of Technology, Guangzhou, 510006, China; The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, South China University of Technology, Guangzhou, 510006, China.