在无氧,有氧和无氧-有氧条件下,和Mn (II/IV) 的相互作用:溶解,氧化和pH的依赖性
Ming Ao1, Shengsheng Sun1, Tenghaobo Deng2
1School of Environmental Science and Engineering, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Sun Yat-sen University, Guangzhou, 510006, China.
Journal of environmental management
|November 3, 2023
概括
矿溶解释放有毒的Cr (VI) 进入土壤和地下水. 氧化,特别是生物的形式,显著加快了这一过程,造成环境风险,而中性条件促进了染色体的稳定性.
科学领域:
- 环境化学环境化学
- 地质化学 地质化学
- 环境科学 环境科学
背景情况:
- 氧化溶解是土壤和地下水中高 (VI) 的关键过程.
- 在自然条件下,氧直接氧化 (III) 是无效的.
- 和氧化物之间的相互作用对于 (VI) 生产至关重要.
研究的目的:
- 研究 (II) 和 (IV) 氧化物对酸盐氧化溶解的作用.
- 评估pH和氧化还原条件 (无毒,有氧,无毒-有氧) 对这些过程的影响.
主要方法:
- 在pH值5,7,9时对酸盐氧化溶解的实验研究.
- 直接氧化氧化的比较,由的催化氧化 (II) 和由生物性氧化物的氧化.
- 在不同氧化还原条件下释放 (VI) 的分析.
主要成果:
- 在水系统中, (III) 直接被O2氧化是缓慢的.
- 生物性氧化物显著增强了酸盐的氧化溶解,比直接的O2氧化或催化氧化释放更多的.
- 酸性和性条件有利于催化氧化,而中性条件提高了染色体的稳定性.
结论:
- 生物性氧化物对环境中的长期染色体稳定性构成重大威胁.
- (II) 和 (III/IV) 氧化物在 (III) 氧化和调动中起着至关重要的作用.
- 湿地和洪水平原等环境中的还氧化物波动可能导致这些过程导致 (VI) 水平升高.
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