GB/T 4701.4-2008Ferrotitanium - Determinatino of manganese content - Arsenite-salt and sodium-salt titrimetric method and periodate photometric method (English PDF)

3.1 Principle

Sample with sulfuric acid, hydrochloric acid decomposition, fuming sulfuric acid heated to take, silver nitrate as a catalyst, plus ammonium persulfate boiling manganese oxide high manganese,

With sodium arsenite - sodium nitrite titration standard solution titration. According to arsenite - sodium nitrite standard titration solution consumption is calculated manganese content.

3.2 Reagents and materials

Unless otherwise indicated in the analysis using only recognized as analytical grade reagents and distilled water or its equivalent purity water.

3.2.1

nitrate, rho1.42g/mL.

3.2.2

hydrochloric acid, 1 + 1.

3.2.3

sulfate, 1 + 3.

3.2.4

sodium chloride solution, 5g/L.

3.2.5

silver nitrate solution, 5g/L.

3.2.6

solution of ammonium persulfate, 250g/L, with the preparation can not be heated to dissolve.

3.2.7 mixed acid

water to 650mL, 100mL slowly added sulfuric acid (rho1.84g/mL), was added 250mL nitric acid cooled (3.2.1), and mix.

3.2.8 Manganese standard solution

3.2.8.1

weighed 1.0000g of manganese metal (purity 99.9%), placed in 250mL beaker, add 20mL sulfuric acid (3.2.3), heating

Dissolved, remove the cooled to room temperature and transferred to 1000mL volumetric flask, dilute with water to volume, and mix. This solution 1mL containing 1.00mg manganese.

3.2.8.2

Pipette 10.00mL manganese standard solution (3.2.8.1), placed in 100mL volumetric flask, dilute with water to volume, and mix. This solution

Liquid 1mL containing 0.10mg manganese.

3.2.9

sodium arsenite - sodium nitrite standard titration solution, 0.02mol/L.

3.2.9.1 preparation

Weigh 0.5000g pure class distinctions trioxide dissolved in 20mL of sodium hydroxide solution (100g/L), and diluted with water […]