与溶解有机物质的基反应的温度依赖性
Yu Lei1,2, Xiaoqin He1, Yu Dang1
1State Key Laboratory of Green Papermaking and Resource Recycling, State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants, School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China.
Environmental science & technology
|October 17, 2025
概括
水温显著影响与溶解有机物 (DOM) 的基反应,影响污染物降解. 了解这种关系是水生化学和先进的氧化过程的关键.
科学领域:
- 环境化学环境化学
- 水生化学 水生化学
- 化学动力学 化学动力学
背景情况:
- 溶解有机物 (DOM) 反应控制水生环境中的基沉积.
- 季节性和区域性温度变化对这些反应的影响尚不清楚.
- 基 (Cl•,Br•,Cl2•-,Br2•-) 是水处理和自然系统中的重要反应物种.
研究的目的:
- 量化素基和DOM之间的反应的温度依赖性.
- 根据DOM属性开发预测反应速率和激活能量的模型.
- 将温度效应整合到动力模型中,以改进微污染物降解预测.
主要方法:
- 测量了四个基与六个DOM分离物反应的第二阶速常量 (k),温度范围为9-39°C.
- 使用阿雷尼乌斯方程来确定明显的激活能量 (Ea).
- 经验模型被开发出来,将Ea和前指数因子 (A) 与大量DOM属性联系起来.
主要成果:
- 速率常数随着基类型和温度而显著变化,在25°C时从10^5到10^8 M^-1 s^-1不等.
- 表面激活能 (Ea) 范围在5.8至34.1kJmol-1之间,表明温度敏感度不同.
- Cl•和Br•反应几乎没有障碍 (平均Ea~10-13kJ mol^-1),而Cl2•-和Br2•-则表现出更强的温度依赖性 (平均Ea>20kJ mol^-1).
结论:
- 温度显著调节与DOM的基反应性,影响它们的环境命运.
- 开发的模型提供了水温,DOM特征和激素动力学之间的定量联系.
- 纳入温度依赖性可以提高动力模型的准确性,用于预测高级氧化过程中的微污染物降解.
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