Instruments and Reagents:
Cat.No. 173016 Spectroquant® VIS Spectrophotometer Prove 100 or
Cat.No. 173017 Spectroquant® UV/VIS Spectrophotometer Prove 300 or
Cat.No. 173018 Spectroquant® UV/VIS Spectrophotometer Prove 600 or
Cat.No. 109748 Spectroquant® Photometer NOVA 30 or
Cat.No. 109751 Spectroquant® Photometer NOVA 60 or
Cat.No. 173632 Spectroquant® Colorimeter Move 100
Cat.No. 114946 Rectangular cells 10 mm and/or
Cat.No. 114947 Rectangular cells 20 mm and/or
Cat.No. 114944 Rectangular cells 50 mm
Cat.No. 114833 Spectroquant® Lead Cell Test
Cat.No. 109717 Spectroquant® Lead Test
Cat.No. 106689 Sodium diethyldithiocarbaminate trihydrate for analysis
Cat.No. 100983 Ethanol for analysis
Cat.No. 109966 Nitric acid 1 mol/l
Cat.No. 109137 Sodium hydroxide solution 1 mol/l
Cat.No. 109535 MColorpHastTM Universal indicator strips pH 0 - 14
Cat.No. 116754 Water for analysis
Cat.No. 114724 Empty cells 16 mm with screw caps
Membranfilter 0.45 μm
Polyethylene syringe, 10 ml, with Luer cone
Sodium diethyldithiocarbaminate solution10 %:
Dissolve 5 g sodium diethyldithiocarbaminate trihydrate for analysis in 45 ml of water for analysis.
Waste water from the metal- and glass-processing industries are normally treated with milk of lime to precipitate metals. However, the resulting high concentrations of Ca2+ tend to interfere with the photometric determination of lead. The procedure described below avoids this type of interference.
Add 10 drops of a 10 % solution of sodium diethyldithiocarbaminate solution to 10 ml of sample solution, shake and aspirate into a 10 ml-PE syringe. Pass the syringe contents through an membrane filter, wash with 10 ml water for analysis and dispose of the filtrate and wash solution. Pass 5 ml ethanol through the same membrane filter. Collect the ethanolic filtrate in a 16-mm round cell, add 5 drops of nitric acid 1 mol/l and place in the thermoreactor at 100 °C for evaporation to dryness.
Add 5 ml of water for analysis to the residue in the round cell and adjust the pH to the required value of 3 - 6 with sodium hydroxide solution. This can be checked using universal indicator strips. This solution can now be used directly for the determination of lead.
Determine with the above mentioned test kits.
Lead content in mg/l Pb = analysis value in mg/l Pb x 0.5