GB/T 3253.2-2008Methods for chemical analysis of antimony and antimony trioxide - Determination of iron content - Orthophenanthroline spectrophotometric method (English PDF)

3.1 commercially available reagents

3.1.1

hydrochloric acid (rho1.19g/mL).

3.1.2

nitrate (rho1.42g/mL).

3.1.3

hydrobromic acid (rho1.50g/mL).

3.1.4

ammonia (rho0.90g/mL).

3.1.5 chloroform

3.2 solution

3.2.1

hydrochloric acid (1 + 1).

3.2.2

phenanthroline solution (2.5g/L).

3.2.3

thiocyanate solution (200g/L).

3.2.4 hydroxylamine hydrochloride solution (100g/L)

100g of hydroxylamine hydrochloride was weighed into a beaker of 1000mL was added 500mL of water dissolved, aqueous ammonia (3.1.4) neutralized by adding

20mL phenanthroline solution (3.2.2), boiled for 2min, remove the cooled to room temperature. Added 20mL thiocyanate solution (3.2.3), shift

1000mL into a separatory funnel, was added in chloroform (3.1.5) (each 10mL) oscillation extraction until the organic phase as a colorless, have discarded

The organic phase. The aqueous phase was transferred to a glass bottle, diluted with water to 1000mL, and mix.

3.2.5 sodium acetate solution (200g/L)

200g of anhydrous sodium acetate was weighed into a beaker of 1000mL was added 500mL of water was heated to dissolve, was added hydroxylamine hydrochloride solution 20mL

Solution (3.2.4), was added 20mL phenanthroline solution (3.2.2), boiled for 2min, remove the cooled to room temperature. KSCN was added 20mL

Solution (3.2.3) and transferred to 1000mL separatory funnel, was added in chloroform (3.1.5) (each 10mL) oscillation extraction until the organic

Phase colorless, organic phase was discarded. The aqueous phase was transferred to a glass bottle, diluted with water to 1000mL, and mix.

3.2.6 potassium sodium tartrate solution (250g/L)

Weigh 250g of potassium sodium tartrate (KNaC4H4O6 · 4H2O), placed in 1000mL beaker, add 500mL water dissolved by heating,

20mL added hydroxylamine hydrochloride solution (3.2.4), 20mL phenanthroline solution (3.2.2), boiled for 2min, removed, cooled to room temperature. plus

Into 20mL thiocyanate solution (3.2.3) and transferred to 1000mL separatory funnel, was added in chloroform (3.1.5) (each 10mL)

Oscillation extraction until the organic phase as a colorless, organic phase was discarded. The aqueous phase was transferred to a glass vial is diluted with water to 1000mL, and mix.

3.3 iron standard solution

3.3.1 Iron standard stock solution (100µg/mL)