Motamedi Mahsa, Yerushalmi Laleh, Haghighat Fariborz, Chen Zhi, Zhuang Yanbin
Department of Building, Civil and Environmental Engineering, Concordia University, Montreal, H3G 1M8, Canada.
Department of Building, Civil and Environmental Engineering, Concordia University, Montreal, H3G 1M8, Canada.
Chemosphere. 2023 Jun;326:138363. doi: 10.1016/j.chemosphere.2023.138363. Epub 2023 Mar 10.
Polybrominated diphenyl ethers (PBDEs) are halogenated organic compounds that are among the major pollutants of water, and there is an urgent need for their removal. This work compared the application of two techniques, i.e., photocatalytic reaction (PCR) and photolysis (PL), for 2,2,4,4- tetrabromodiphenyl ether (BDE-47) degradation. Although a limited degradation of BDE-47 was observed by photolysis (LED/N), photocatalytic oxidation by using TiO/LED/N proved to be effective in the degradation of BDE-47. The use of a photocatalyst enhanced the extent of BDE-47 degradation by around 10% at optimum conditions in anaerobic systems. Experimental results were systematically validated through modeling with three new and powerful Machine Learning (ML) approaches, including Gradient Boosted Decision Tree (GBDT), Artificial Neural Network (ANN), and Symbolic Regression (SBR). Four statistical criteria (Coefficient of Determination (R), Root Mean Square Error (RMSE), Average Relative Error (ARER), and Absolute Error (ABER)) were calculated for model validation. Among the applied models, the developed GBDT was the desirable model for predicting the remaining concentration (Ce) of BDE-47 for both processes. Total Organic Carbon (TOC) and Chemical Oxygen Demand (COD) results confirmed that BDE-47 mineralization required additional time than its degradation in both PCR and PL systems. The kinetic study demonstrated that BDE-47 degradation for both processes followed the pseudo-first-order form of the Langmuir-Hinshelwood (L-H) model. More importantly, the calculated electrical energy consumption of photolysis was shown to be ten percent higher than that for photocatalysis, possibly due to the higher irradiation time required in direct photolysis, which in turn increases electricity consumption. This study is useful in proposing a feasible and promising treatment process for the degradation of BDE-47.
多溴二苯醚（PBDEs）是卤代有机化合物，属于水的主要污染物，因此迫切需要将其去除。本研究比较了光催化反应（PCR）和光解（PL）两种技术对2,2,4,4-四溴二苯醚（BDE-47）的降解效果。虽然通过光解（LED/N）观察到BDE-47的降解有限，但使用TiO/LED/N进行光催化氧化被证明对BDE-47的降解是有效的。在厌氧系统的最佳条件下，使用光催化剂可使BDE-47的降解程度提高约10%。通过使用三种新的强大机器学习（ML）方法进行建模，包括梯度提升决策树（GBDT）、人工神经网络（ANN）和符号回归（SBR），对实验结果进行了系统验证。计算了四个统计标准（决定系数（R）、均方根误差（RMSE）、平均相对误差（ARER）和绝对误差（ABER））用于模型验证。在所应用的模型中，所开发的GBDT是预测两个过程中BDE-47剩余浓度（Ce）的理想模型。总有机碳（TOC）和化学需氧量（COD）结果证实，在PCR和PL系统中，BDE-47矿化所需的时间比其降解所需的时间更长。动力学研究表明，两个过程中BDE-47的降解均遵循Langmuir-Hinshelwood（L-H）模型的准一级形式。更重要的是，计算得出的光解电能消耗比光催化高10%，这可能是由于直接光解所需的照射时间更长，进而增加了电力消耗。本研究有助于提出一种可行且有前景的BDE-47降解处理工艺。
