YB/T 4225-2010 English PDF (YBT4225-2010)

Delivery: 3 seconds. Download true-PDF + Invoice.
Get QUOTATION in 1-minute: Click YB/T 4225-2010
Historical versions: YB/T 4225-2010
Preview True-PDF (Reload/Scroll if blank)

YB/T 4225-2010: Method for determination of silicon dioxide content in arenaceous quartz
YB/T 4225-2010
YB
FERROUS METAL INDUSTRY STANDARD
OF THE PEOPLE’S REPUBLIC OF CHINA
ICS 29.050
Q 51
Method for determination of silicon dioxide content in
arenaceous quartz
ISSUED ON: NOVEMBER 11, 2010
IMPLEMENTED ON: MARCH 01, 2011
Issued by: Ministry of Industry and Information Technology of the
People's Republic of China
Table of Contents
Foreword ... 3
1 Scope ... 4
2 Normative references ... 4
3 Principle ... 4
4 Instruments ... 4
5 Reagents ... 5
6 Preparation of samples ... 5
7 Test procedures ... 5
8 Analysis results ... 6
9 Precision ... 6
10 Test report ... 6
Method for determination of silicon dioxide content in
arenaceous quartz
1 Scope
This Standard specifies the principle, instruments, sample requirements, test
procedures and test results of the determination of silicon dioxide content in
arenaceous quartz.
This Standard applies to the determination of silicon dioxide content in
arenaceous quartz for carbon production.
2 Normative references
The following referenced documents are indispensable for the application of
this document. For dated references, only the edition cited applies. For undated
references, the latest edition of the referenced document (including any
amendments) applies.
GB/T 8170 Rules of rounding off for numerical values and expression and
judgement of limiting values
3 Principle
The sample is decomposed with hydrofluoric acid and nitric acid. Sulfuric acid
emits smoke to drive off silicon and fluorine. The sample is burned to constant
weight at high temperature. The silicon dioxide content is calculated according
to the difference between the masses of the sample before and after the
hydrofluoric acid treatment. The chemical reaction is as follows;
4 Instruments
4.1 Balance, with a division of 0.1 mg.
4.2 Platinum crucible, 30 mL.
4.3 Automatic temperature control drying oven.
4.4 Muffle furnace: The maximum operating temperature is not less than
1000 °C, and it can automatically control the temperature.
5 Reagents
5.1 Nitric acid, ρ: 1.40 g/cm3, analytically pure.
5.2 Sulfuric acid (1:3), analytically pure.
5.3 40 % hydrofluoric acid, analytically pure.
6 Preparation of samples
PUT the sample in an oven at (120 °C ± 5 °C) for 2 h to dry; TAKE it out to cool.
USE the quarter method to divide 50 g ~ 60 g of the sample. USE a grinder to
pulverize it to a particle size of less than 150 μm. PACK the prepared sample
into the sample bag and put it in the drying oven for later use.
7 Test procedures
7.1 Sample mass
WEIGH 0.5 g of sample, accurate to ±0.001 g.
7.2 Determination
7.2.1 PLACE the sample in a platinum crucible (4.2) that has been made to
constant weight in advance; BAKE it at 120°C ± 5°C for 30 min; TAKE it out;
COOL it to room temperature in a desiccator; WEIGH it as m1.
7.2.2 PLACE the crucible in a fume hood; slowly ADD 5 mL of nitric acid (5.1)
along the wall of the crucible; ADD 3 to 4 drops (about 1 mL) of sulfuric acid
(5.2); gradually ADD 5 mL ~ 10 mL of hydrofluoric acid (5.3); PUT the crucible
on a low-temperature electric furnace; HEAT to completely decompose the
sample.
7.2.3 If the sample is not decomposed, continue to add 5 mL ~ 10 mL of
hydrofluoric acid (5.3) and 3 mL of nitric acid (5.1) until the test solution is
completely clear.
7.2.4 Continue to evaporate until the sulfuric acid smoke is exhausted and then
take it down.