Grantee Research Project Results
2003 Progress Report: Development of Electrochemical Techniques for the Detection/Quantification of Mercury using Boron-Doped Diamond Electrodes
EPA Grant Number: R829410E02Title: Development of Electrochemical Techniques for the Detection/Quantification of Mercury using Boron-Doped Diamond Electrodes
Investigators: Seehra, Mohindar S.
Institution: West Virginia University
EPA Project Officer: Chung, Serena
Project Period: October 1, 2001 through September 30, 2003
Project Period Covered by this Report: October 1, 2002 through September 30, 2003
Project Amount: $274,928
RFA: EPSCoR (Experimental Program to Stimulate Competitive Research) (2001) RFA Text | Recipients Lists
Research Category: EPSCoR (The Experimental Program to Stimulate Competitive Research)
Objective:
The objective of this research project is to develop electrochemical techniques using boron-doped diamond (BDD) electrodes for the rapid onsite detection and quantification of mercury in the ppb range in solutions. Potential applications of such sensors include mercury emissions from coal-fired power plants and mercury in aquatic systems.
Progress Summary:
We have shown that the highly BDD electrode films grown on silicon substrates can be used to develop calibration curves for the detection of mercury. The anodic differential pulse voltammetric technique was used for detecting ppb-level concentrations of Hg. The focus of our experiments during Year 2 of the project has been to develop calibration curves using standard mercury solutions to detect mercury in the 1-50 ppb range. Certain complications had to be overcome. First, the presence of chloride and nitrate ionic species in the solutions affects the sensitivity for mercury detection. Second, the formation of mercurous chloride affects the reproducibility of the calibration. A summary of our initial results on mercury detection has appeared in a recent publication, (Manivannan, et al., 2002) and these results also were presented at two recent conferences. We now are developing a rotating disk electrode technique and the standard addition method using free-standing diamond electrodes for mercury detection.
During the past year, we also focused on the detection of mercury in various electrolytes and in the presence of ultrasound using polished, free-standing BDD electrodes. We investigated underpotential deposition of mercury in phosphate and sulfate media in the hope that more positive deposition potentials could be used. Ultrasound experiments led to the detection of 5 ppb Hg2+ using a 20-minute deposition time at an ultrasound intensity of 13 W/cm2 and an electrode-tip separation of 10 mm. Results of repeated runs, however, indicated that ultrasound probably "scrubs" off the deposited Hg0, which can evaporate from solution because of the degassing effect of ultrasound.
Future Activities:
Future work will explore ways to improve adhesion of deposited mercury to the electrode surface in the presence of ultrasound, and the possibility of using ultrasound to improve currents obtained with stirring. Our future experiments will focus on the measurements using a newly bought portable PalmSens online monitor. We will combine this unit and the RDE unit to achieve the best results.
Journal Articles on this Report : 2 Displayed | Download in RIS Format
| Other project views: | All 15 publications | 5 publications in selected types | All 4 journal articles |
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Manivannan A, Seehra MS, Tryk DA, Fujishima A. Electrochemical detection of ionic mercury at boron-doped diamond electrodes. Analytical Letters 2002;35(2):355-368. |
R829410E02 (2002) R829410E02 (2003) |
not available |
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Manivannan A, Ramakrishnan L, Seehra MS, Granite E, Butler J, Fujishima A. Trace analysis of mercury at boron-doped diamond electrodes. Journal of Electroanalytical Chemistry. 2005; 577(2): 287-293. |
R829410E02 (2003) |
not available |
Supplemental Keywords:
water, innovative technology, analytical, air, waste, engineering, chemistry, physics, incineration, combustion, air pollution, air quality, air sampling, boron doped diamond, BDD, electrodes, combustion flue gases, combustion gases, combustion kinetics, electrochemical technology, mercury, mercury abatement technology, mercury emissions water, monitoring, analytical innovative technology., RFA, Air, Scientific Discipline, Waste, Ecology, Engineering, Chemistry, & Physics, Incineration/Combustion, air quality, mercury , mercury absorbtion, air sampling, combustion kinetics, combustion gases, electrochemical technology, boron doped diamoond electrodes, mercury abatement technology, air pollution, mercury monitoring, mercury emissions, combustion flue gasesProgress and Final Reports:
Original AbstractThe perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.