Title of article :
A straightforward wet-chemistry method for the determination of solid and gaseous mercury fractions in Backlight Cold Cathode Fluorescence Lamps
Author/Authors :
Figi، نويسنده , , Renato and Nagel، نويسنده , , Oliver and Hagendorfer، نويسنده , , Harald، نويسنده ,
Issue Information :
ماهنامه با شماره پیاپی سال 2012
Pages :
5
From page :
134
To page :
138
Abstract :
Backlight Cold Cathode Fluorescence Lamps (B-CCFLs) are already applied in many electronic consumer products such as LCD screens, flat screen TVs, and laptop monitors. In consequence, an increase of such products entering the waste streams can be expected in the near future. As a result of the mercury (Hg) employed in such lamps, the development of recycling techniques to create a best practical environmental option for appropriate end-of-life strategies are necessary. For this purpose the knowledge about speciation in terms of solid and gaseous state of Hg in such lamps is inevitable. However, analytical techniques to discriminate solid and gaseous Hg require a special setup, not available in most routine laboratories. Thus a straightforward and cost efficient analytical technique is of need. s work we describe sample preparation procedures and analysis techniques, which only require equipment already available in most routine laboratories. The volatile fraction is extracted with a KMnO4 solution utilizing a novel approach, taking the advantage that the B-CCFL glass tubes have a negative pressure. Thus the extraction solution is directly sucked into the tube where the volatile Hg-fraction is immediately extracted. Subsequently, the solid fraction is dissolved via microwave assisted pressure acid digestion after cryo-milling. Analysis for both fractions took place employing a cold vapor atomic absorption system. ve the new method is fit for purpose, spiking experiments and analysis of reference materials (when available) was performed with recoveries being between 90% and 110%. First results obtained for a stack of lamps from an used LCD-TV display reveal that solid Hg fractions in all lamps show a variation of 20% between samples whereas the gaseous Hg content can vary up to 600%.
Keywords :
Wet chemistry , Cold vapor atomic absorption spectroscopy , Backlight Cold Cathode Fluorescence Lamps , Mercury speciation
Journal title :
Talanta
Serial Year :
2012
Journal title :
Talanta
Record number :
1663985
Link To Document :
بازگشت