GB/T 5121.20-2008Methods for chemical analysis of copper and copper alloys - Part 20:Determination of zirconium content (English PDF)

3.1

hydrochloride (rho1.19g/mL).

3.2

perchlorate [Ba (HClO4) = 5.0mol/L]. Pipette 278mL perchloric acid (rho1.67g/mL) was diluted with water to 500mL mix.

3.3

Hydrogen peroxide (rho1.11g/mL).

3.4 Na2EDTA solution (10g/L)

Weigh 10gNa2EDTA dissolved in 400mL warm water cooled to room temperature, diluted with water to

1000mL mix.

3.5

xylenol orange solution (1g/L) stored in a brown bottle.

3.6 Storage zirconium standard solution

Weigh 0.1000g pure zirconium (Zr mass fraction of > 99.9%) were placed in a platinum dish, add 10mL sulfuric acid (1 + 1), 1mL hydrofluoric acid (rho1.16g/mL), heated until completely dissolved, the solution was evaporated to take a small amount of sulfur trioxide smoke. After cooling, along

Dish wall purge a small amount of water, shake the solution and re-evaporated to began to take a small amount of sulfur trioxide smoke. Cooled to room temperature, slowly purged about 25mL

Water, mix cooled to room temperature and transferred to 100mL plastic volumetric flask, dilute with water to volume, and mix. 1mL solution containing 1mg zirconium.

3.7 Zirconium standard solution

Pipette 10.00mL zirconium standard stock solution (3.6) in 500mL volumetric flask, was added 30mL of hydrochloric acid (3.1),

Diluted with water to the mark, and mix the solution 1mL containing 20µg zirconium.

6.1 Sample

Table 1. Weigh the sample (5) accurate to 0.0001g.