Analytical Method: Copper (total) in feedstuffs

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. 114553  Spectroquant^® Copper Cell Test
Cat.No. 114767  Spectroquant^® Copper Test
Cat.No. 100731  Sulfuric acid 95 - 97 % for analysis
Cat.No. 107209  Hydrogen peroxide 30 % (Perhydrol^®) for analysis
Cat.No. 105432  Ammonia solution 25 % for analysis
Cat.No. 109535  MColorpHastTM Universal Indicator strips pH 0 - 14
Cat.No. 116754  Water for analysis
Folded filter
 
Sample preparation:
Mix 1.0 g of finely powdered material with 15 ml of sulfuric acid 95 - 97 % in a 400-ml glass beaker covered with a watch glass and heat for 30 minutes on the heating plate. After cooling, slowly and cautiously pipette 15 ml of Perhydrol^® to the solution. Heat the solution once again in the covered beaker until it becomes colorless.
Afterwards heat the mixture for a short time in the uncovered beaker in order to evaporate the acids, until only a moist crystalline residue remains. After a further addition of 15 ml Perhydrol^®, evaporate the mixture once again almost to dryness.
 
Dissolve this residue in water for analysis, transfer to a 100-ml volumetric flask and fill up to volume with water for analysis. After mixing, filter through a folded filter, in order to remove the silicates. In certain cases it may be necessary to adjust the pH before analysis. The optimum pH range is 4 - 10; adjust with 25 % ammonia solution and check by using Universal Indicator strips pH 0 - 14.
 
Analysis:
Determine with the above mentioned test kits
 
Calculation:
Copper (total) content in mg/kg Cu = analysis value in mg/l Cu x 100