Ammonical Nitrogen Measurement Calculator IS 3025

Ammonical Nitrogen Measurement Ammonical Nitrogen Calculation


Test-I
ml
ml
N
ml
Test-II
ml
ml
N
ml
Test-III
ml
ml
N
ml

What is Ammoniacal nitrogen Test?

Ammoniacal nitrogen (NH3-N) is a measure for the amount of ammonia, a toxic pollutant often found in landfill leachate and in waste products, such as sewage, liquid manure and other liquid organic waste products.


Principle

Ammonia after distillation is dissolved in boric acid and mixed indicator and can be titrated with H2SO4. Boric acid is so weak acid that it does not interfere with acidimetric titration.


Apparatus
  • Distillation apparatus (All borsillicate glass appratus)
  • Pipette
  • Heating Mantle
  • Volumetric Flask
  • Burets borosilicate glass

Interferences

Residual chlorine reacts with ammonia; remove by sample pretreatment.


Range

Minimum Detection limit of Ammonical Nitrogen is 0.05 mg/L.

Preparation of Reagent

Reagent
  • Ammonia Free Water
  • Borate Bufffer Solution
  • Sodium Hydroxide, 6N
  • Decholorinating reagent
  • Neutralization agent: NaOH 1N, H2SO4 1N
  • Mix indicator Solution
  • Boric acid
  • Sulphuric Acid
  • Methyl red and methyl blue indicator

Reagent Preparation
  • Ammonia Free Water
    Distillation –Eliminate traces of Ammonia in distilled water by adding 0.1 mL of Conc. H2SO4 in 1L distilled water and redistillation, Discard the first 100 ml distilled.
  • Borate Buffer solution
    Add 88 mL 0.1 N NaOH solution to 500 mL approximately 0.025 M Sodium tetra borate solution or 9.5 g sodium tetra borate and dilute to 1000 mL with distilled water.
  • Sodium Hydroxide, 6N
    Dissolve 24 g NaOH in distilled water and dilute up to 100 mL.
  • Mix Indicator Solution
    (A) Dissolved 0.200 g Methyl red indicator in 100 mL 95% Ethyl or Isopropyl alcohol. (B) Dissolve 0.100 g Methyl Blue in 50 mL 95% ethyl or Isopropyl alcohol. Combine two solutions. Prepare Monthly.
  • Boric Acid
    Dissolve 20 g Boric acid (H3BO3) in distilled water, add 10 mL mixed indicator solution and dilute to 1000 mL.
  • Standard Sulphuric Acid
    Dissolve 10 mL 1N H2SO4 dilute to 500 mL with distilled water.

Calculation of Ammonical Nitrogen

Ammonical Nitrogen (mg/L) = A-B×280mL of sample

If Normality of H2SO4 is other than 0.02 N, use following formula.

Ammonical Nitrogen (mg/L) = A-B×N×14×1000mL of sample

Where,
  • A = Sample reading
  • B = Blank reading