线性自由能量关系用于预测Fe (II) - 黑马和Fe (II) - 戈伊氧化还原对的弹药化合物减少速率常数
Paula A Cárdenas-Hernández1, Kevin Hickey1, Dominic M Di Toro1
1Department of Civil and Environmental Engineering, University of Delaware, Newark, Delaware 19716, United States.
Environmental science & technology
|August 23, 2023
概括
一个新的模型预测了铁矿物质的弹药化合物 (MC) 减少率. 这种线性自由能量关系 (LFER) 适用于各种MC,改善环境命运预测.
科学领域:
- 环境化学环境化学
- 地质化学 地质化学
- 整治科学 整治科学
背景情况:
- 铁矿物质的非生物降解是地下环境中弹药化合物 (MC) 降解的关键过程.
- 现有的模型无法预测结构多样化的MCs由铁 (oxyhydr) 氧化物减少的速度.
研究的目的:
- 开发一种预测模型,用于铁矿物质对各种MCs的非生物降解率.
- 调查MC结构和环境条件对减少率的影响.
主要方法:
- 进行了批量实验,以测量在有水性Fe存在的情况下,由血和戈伊减少MC的速率常数.
- 这项研究研究了三类MC:聚酸芳,胺和醇.
- 一个线性自由能量关系 (LFER) 是基于MC的降解潜力和铁系统热力学.
主要成果:
- 发现表面面积规范化减速常数 (kSA) 取决于MC的一电子减速潜力和铁氧化物-Fe (II) 系统的pe/pH.
- 一个单一的LFER成功地描述了跨越六个数量级的MC减速常数.
- 结果表明,通过铁氧化物-Fe (II) 配对,直至速度限制步骤,各种MCs具有共同的降解机制.
结论:
- 开发的LFER模型提供了一种可靠的方法来预测各种弹药化合物的减少率.
- 这项研究扩大了LFER模型对传统和新兴MCs环境命运评估的适用性.
- 这些发现为铁矿物质对酸芳化合物的还原性降解提供了机械的见解.
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