GB/T 4698.23-2017Methods for chemical analysis of titanium sponge, titanium and titanium alloys - Part 23: Determination of palladium content - Stannous choride-potassium iodide spectrophotometry and inductively coupled plasma atomic emission spectrometry (English PDF)

2.1 Method summary

The sample is dissolved in hydrochloric acid, hydrofluoric acid and nitric acid. In the presence of acetone, palladium forms a blue-green complex with stannous chloride-potassium iodide,

The absorbance of the photometer at 595 nm was measured.

2.2 Reagents

Unless otherwise specified, only reagents that are identified as analytically pure and laboratory-grade water are used in the analysis.

2.2.1

Hydrofluoric acid (p = 1.13 g/mL).

2.2.2

Nitric acid (p = 1.42 g/mL).

2.2.3

Acetone.

2.2.4

Hydrochloric acid (1 1).

2.2.5 Stannous chloride solution (300g/L)

Weigh 45g of stannous chloride (SnCL2 · 2H2O) in a 150mL beaker, add 30mL

Hydrochloric acid (2.2.4), 15mL of water, heated to dissolve the solution to clarify, cooled, add water to 150mL, and mix. Store in grinding mouth reagent bottle.

2.2.6

potassium iodide solution (500g/L), stored in grinding mouth reagent bottles, protected from light.

2.2.7

palladium standard storage solution Weigh 0.5000g metal palladium (wPd >= 99.99%) in 250mL beaker, add 30mL aqua regia, add

Heat dissolved, evaporated to dryness. Add 5 mL of hydrochloric acid (rho = 1.19 g/mL) and dry to dryness. Join 30mL hydrochloric acid (2.2.4), heated to dissolve salts,

Cooling, into 1000mL volumetric flask, diluted with water to the mark, mix well. This solution 1 mL contains 500 µg of palladium.

2.2.8

Palladium standard solution Pipette 10.00mL palladium standard stock solution (2.2.7) in 100mL volumetric flask, diluted with water to the mark, mixed uniform. 1 mL of this solution contains 50 µg of palladium.

2.3 Instruments

Spectrophotometer.

2.4 sample

In accordance with the promulgated sponge titanium, titanium and titanium alloy take sample preparation standards.