PRINCIPLE:
The Manganese
content of the sample is determined by AAS. For dissolved Manganese, the
filtrated sample is directly aspirated to the atomizer. For total recoverable
Manganese an acid digestion procedure is
done prior to aspiration of the sample.
Limit
of Detection: 0.04 mg/L
REAGENTS:
- Hydrochloric Acid – Concentrated
- Nitric Acid: Concentrated
- Nitric Acid: (1:499)
- Manganese Stock Solution: Merck
1000 mg/L NIST Certified Reference Material or Dissolve 1.0 gm of
Manganese Metal in 10 ml conc. HCl mixed with 1 ml conc. HNO3
Dilute to 1000 ml with water (1 ml = 1 mg of Mn)
PROCEDURE:
Preparation
of Standard solution: Prepare a regent blank and a
series of 100 ml standards containing 0.04, 0.08, 0.12, 0.16 and 0.20 mg/L of
manganese by diluting a
Suitable volume of the standard solution
with dilute nitric acid.
Sample
Preparation: To 100 ml portion of the acidified
sample add 0.5 ml of nitric acid
If total recoverable Manganese is to be
determined, add 5 ml of concentrated HCl and
Filter the sample through acid washed
filter paper. Make up to 100 ml in a volumetric flask.
Analysis: Operate the instrument as per SOP. Aspirate nitric acid
(1:499) as blank. Then aspirate series of
standards and then aspirate the sample solution.
Read the concentration in mg/L of Manganese
directly.
REFRENCE:
APHA 22nd Edition
3111 B/ IS 3025 (Part 59) - 2003