Test Items

superior quality

 First grade

Nitrogen content (dry basis) / %

  ≥46.3  

  ≥46.3  

Biuret / %

 ≤0.5   

≤0.9

Water / %

≤0.3

 ≤0.5   

Iron (Fe) / %

  ≤0.0005

  ≤0.0005

Sulfate (SO42 -) / %

    ≤0.005     

 ≤0.01

Alkalinity (in NH3) / %

 ≤0.01

 ≤0.01

Water insoluble / %

  ≤0.005 

 ≤0.01