Determination of Ultra-Trace Amounts of Total Mercury by Gold Amalgamation-Cold Vapor AAS in Geothermal Water Samples by Using Ozone as Pretreatment Agent

Abstract

Mercury in geothermal water samples, pretreated with ozone, was subjected to reduction-vaporization by use of tin(II) chloride. The mercury vapor was concentrated with a porous gold collector. Afterward, mercury vapor which had evolved from the heated collector was determined by cold vapor atomic absorption spectrometry (CVAAS). By using ozone as pretreatment agent, the time for the decomposition could be shortened and the blank value of mercury from reagents used was reduced. The permissible amounts of sulfide and thiosulfate ions, the main interference ions in reduction-vaporization of mercury, were 25 and 100 mg dm-3, respectively. It means that the present method provides an improvement in the permissible amounts of these ions by several hundred times in comparison with the methods using no ozone. Ozone was also found to be effective as the pretreatment agent for organic mercury. The present approach was proved to be satisfactory as the pretreatment of the quantitative analysis of ultra-trace amounts of total mercury in geothermal water samples.

Development of Isotope Dilution Cold Vapor Inductively Coupled Plasma Mass Spectrometry and Its Application to the Certification of Mercury in NIST Standard Reference Materials

“…The sensitivity of ID-CV-ICPMS is competitive with CVAAS, which often incorporates sample preconcentration routines. ,,, Sample preconcentration is not restricted to any particular instrumental technique and could be applied to ID-CV-ICPMS, if necessary.…”

“…Clevenger, Smith, and Winefordner published a 1997 review article that surveys the instrumental techniques used for the quantitation of mercury. 2 The atomic spectroscopic methods used for the determination of mercury include atomic absorption spectroscopy, [3][4][5][6][7][8][9][10] atomic fluorescence spectroscopy, [11][12][13][14][15][16][17] coupled plasma mass spectrometry (ICPMS). [18][19][20][21][22][23][24][25][26][27][28][29][30][31] The ability to monitor isotope ratios using ICPMS advantageously allows for the high accuracy technique of isotope dilution to be implemented.…”

“…Clevenger, Smith, and Winefordner published a 1997 review article that surveys the instrumental techniques used for the quantitation of mercury . The atomic spectroscopic methods used for the determination of mercury include atomic absorption spectroscopy, − atomic fluorescence spectroscopy, − and inductively coupled plasma mass spectrometry (ICPMS). − The ability to monitor isotope ratios using ICPMS advantageously allows for the high accuracy technique of isotope dilution to be implemented , However, the ID-ICPMS technique employed for mercury in solution can still suffer from long mercury washout times, reduced sensitivity, memory effects, and isotope ratio imprecision.…”

Flow system for pre-concentration and spectrophotometric determination of reactive mercury

“…The effect of concomitants on the reduction of Hg(II) by Sn(II) and recovery of the Hg 0 formed has been established elsewhere [29][30][31] and have not been repeated here. The effect of concomitants was previously observed for the presence of sulphide, chloride, copper and tellurium, for concentration levels that are not usually observed in effluent samples, the application for which this method has been developed.…”

Determination of Hg in water by CVAAS using 2-aminothiazole modified silica

“…Mercury contamination in environmental samples is usually caused by less than 1 mg L -1 of this element, thus requiring highly sensitive techniques to determine and quantify its presence. Several analytical techniques exist to determine mercury at trace levels [7][8][9][10][11][12][13][14][15][16][17][18][19][20]. One of these techniques is cold vapor atomic absorption spectrometry (CVAAS), which is suitable due to its high sensitivity for accurate determinations of mercury [11,14,18].…”