GB/T 4698.4-2017Methods for chemical analysis of titanium sponge, titanium and titanium alloys - Part 4: Determination of manganese content - Potassium periodate spectrophotometry and inductively coupled plasma atomic emission spectrometry (English PDF)

2.1 Method summary

The sample was dissolved with hydrofluoric acid and sulfuric acid. Titanium (IV) is oxidized from titanium in the low valence state to nitric acid, fluoride is complexed with boric acid, potassium iodate

Manganese (II) is oxidized to manganese (VII) and its absorbance is measured at a spectrophotometer wavelength of 525 nm.

Coloring solution containing more than 1.0mg of chromium interference. A solution of sodium nitrite was added dropwise to discolor the permanganic acid and the solution was discolored

Correction eliminates chromium interference. Other elements do not affect the determination.

2.2 Reagents

Unless otherwise stated, only reagents identified as analytical grade and laboratory grade II water were used in the analysis.

2.2.1

boric acid.

2.2.2

potassium periodate.

2.2.3

Nitric acid (p = 1.42 g/mL).

2.2.4

hydrofluoric acid (1 1).

2.2.5

sulfuric acid (1 1).

2.2.6

sodium nitrite solution (20g/L), when used with the current.

2.2.7

Titanium metal (wTi not less than 99.95%, wMn < 0.001%).

2.2.8

manganese standard storage solution Weigh 1.0000g beforehand washed with sulfuric acid (1 3) surface oxide and then washed with water and dried gold

Manganese (wMn>=99.95%) in 100mL beaker, add 20mL sulfuric acid (2.2.5), dissolved by heating, cooling. Move into 1000mL capacity

Bottle, diluted with water to the mark, mix well. 1 mL of this solution contains 1.0 mg of manganese.

2.2.9

manganese standard solution Pipette 50.00mL manganese standard stock solution (2.2.8) in 500mL volumetric flask, diluted with water to the mark, mixed uniform. 1 mL of this solution contains 100 µg manganese.

2.3 Instruments

Spectrophotometer.

2.4 sample

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