Hg(0) oxidative absorption by K(2)S(2)O(8) solution catalyzed by Ag(+) and Cu(2+)
Xinhua Xu1, Qunfeng Ye, Tingmei Tang
1Department of Environmental Engineering, Zhejiang University, Hangzhou 310027, People's Republic of China. xuxinhua@zju.edu.cn
Journal of Hazardous Materials
|March 21, 2008
Summary
This study investigated the oxidation of gaseous elemental mercury (Hg(0)) using potassium persulfate (KPS) with silver (Ag+) and copper (Cu2+) catalysts. Silver ions demonstrated superior catalytic activity, significantly enhancing mercury removal efficiency.
Area of Science:
- Environmental Chemistry
- Atmospheric Chemistry
- Catalysis
Background:
- Gaseous elemental mercury (Hg(0)) is a major environmental pollutant.
- Aqueous phase oxidation is a key process for mercury removal.
- Potassium persulfate (KPS) is a potential oxidant for mercury remediation.
Purpose of the Study:
- To investigate the aqueous phase oxidation of gaseous Hg(0) using KPS.
- To evaluate the catalytic effects of Ag+ and Cu2+ on this oxidation process.
- To determine the influence of various experimental parameters on mercury removal efficiency.
Main Methods:
- Experiments were conducted in a glass bubble column reactor.
- Gaseous Hg(0) and aqueous Hg(2+) concentrations were measured using cold vapor generation atomic absorption spectrometry (CVAAS).
- The effects of KPS concentration, catalyst type and concentration, pH, temperature, Hg(0) inlet concentration, and tertiary butanol (TBA) were studied.
Main Results:
- Mercury removal efficiency increased with higher KPS and catalyst concentrations.
- Ag+ exhibited a more effective catalytic effect than Cu2+.
- High temperature and TBA addition reduced oxidation efficiency, while neutral pH and high Hg(0) inlet concentration favored removal.
Conclusions:
- KPS oxidation catalyzed by Ag+ and Cu2+ is an effective method for removing gaseous Hg(0).
- Optimization of catalyst type, concentration, and reaction conditions can maximize mercury removal.
- The study proposes a possible catalytic oxidation mechanism for gaseous mercury by KPS.
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