SOP for STANDARD WORKING PROCEDURE FOR ESTIMATION OF MANGANESE

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:

1. Hydrochloric Acid – Concentrated

2. Nitric Acid: Concentrated

3. Nitric Acid: (1:499)

4. 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