Scope:

ASTM E394 is a standard for the determination of iron in trace quantities using the 1,10-phenanthroline test method. This test method can be used to determine trace levels of iron in a wide range of products, as long as the iron and sample matrix have been properly prepared and made soluble in water or another acceptable solvent. The amount of color created in this procedure is assumed to be proportionate to the amount of iron in the test solution and the calibration curve is linear over the spectral range.

Test Procedure:

The 1,10-phenanthroline combination with iron (II) ion is measured photometrically in the ASTM E394 test technique. With the addition of hydroxylamine hydrochloride, the sample is dissolved in a suitable solvent and the iron is reduced to a divalent state. After that, 1,10-phenanthroline is added to bring out the hue. The absorbance of the solution is measured using an appropriate photometer at approximately 510 nm after a brief reaction period. The solution’s absorbance remains steady for at least several months after the color has developed.

Video 01: Measurement of Iron in Water by Phenanthroline Method

Specimen Size: 

The ASTM E394 technique uses samples with a pH of less than 2 in their solutions.

Data:

As per the ASTM E394, the iron content of the sample is calculated as follows:

Iron µg/g (ppm) = B/W

where:

B = micrograms of iron found

W = grams of sample

The iron content is reported to the nearest 0.01 µg/g(ppm).

Conclusion:

ASTM E394 covers the determination of iron in trace quantities using the 1,10-phenanthroline method. This test method can be used to determine trace levels of iron in a wide range of products.