PDF GB/T 687-2011 English (GB/T 687-1994: Older version)
Search result: GB/T 687-2011 (GB/T 687-1994 Older version)
| Standard ID | Contents [version] | USD | STEP2 | [PDF] delivered in | Name of Chinese Standard | Status |
| GB/T 687-2011 | English | 150 |
Add to Cart
|
0-9 seconds. Auto-delivery.
|
Chemical reagent -- Glycerol
| Valid |
| GB/T 687-1994 | English | 279 |
Add to Cart
|
3 days
|
Chemical reagent. Glycerol
| Obsolete |
| GB 687-1977 | English | 199 |
Add to Cart
|
2 days
|
Chemical reagents--Glycerin
| Obsolete |
PDF Preview: GB/T 687-2011
GB/T 687-2011: PDF in English (GBT 687-2011) GB/T 687-2011
NATIONAL STANDARD OF THE
PEOPLE’S REPUBLIC OF CHINA
ICS 71.040.30
G 63
Replacing GB/T 687-1994
Chemical reagent - Glycerol
(ISO 6353-3:1987, Reagents for chemical analysis -
Part 3: Specifications - Second series, NEQ)
ISSUED ON: MAY 12, 2011
IMPLEMENTED ON: DECEMBER 01, 2011
Issued by: General Administration of Quality Supervision, Inspection
and Quarantine;
Standardization Administration of the People’s Republic of
China.
Table of Contents
Foreword ... 3
1 Scope ... 4
2 Normative references ... 4
3 Properties ... 5
4 Specifications ... 5
5 Test ... 6
6 Inspection rules ... 11
7 Packaging and marking ... 11
Chemical reagent - Glycerol
Rational formula: HOCH2CHOHCH2OH
Relative molecular mass: 92.09 (according to the international relative atomic
mass in 2007)
1 Scope
This Standard specifies the properties, specifications, tests, inspection rules,
packaging and marking of glycerol in chemical reagents.
This Standard applies to the inspection of glycerol in chemical reagents.
2 Normative references
The terms in the following documents become the terms of this Standard by
reference to this Standard. For dated references, all subsequent amendments
(not including errata content) or revisions do not apply to this standard. However,
parties to agreements that are based on this Standard are encouraged to study
whether the latest versions of these documents can be used. For undated
references, the latest edition applies to this Standard.
GB/T 601, Chemical reagent - Preparations of reference titration solutions
GB/T 602, Chemical reagent - Preparations of standard solutions for impurity
(GB/T 602-2002, ISO 6353-1:1982, NEQ)
GB/T 603, Chemical reagent - Preparations of reagent solutions for use in
test methods (GB/T 603-2002, ISO 6353-1:1982, NEQ)
GB/T 605, Chemical reagent - General method for the measurement of
colour (GB/T 605-2006, ISO 6353-1:1982, NEQ)
GB/T 610-2008, Chemical reagent - General method for the determination of
arsenic (ISO 6353-1:1982, NEQ)
GB/T 6682, Water for analytical laboratory use - Specification and test
methods (GB/T 6682-2008, ISO 3696:1987, MOD)
GB/T 9728, Chemical reagent - General method for the determination of
sulphate (GB/T 9728-2007, ISO 6353-1:1982, NEQ)
GB/T 9729, Chemical reagent - General method for the determination of
chloride (GB/T 9729-2007, ISO 6353-1:1982, NEQ)
Sucrose and glucose Qualified Qualified
Substances that reduce silver Qualified Qualified
Readily carbonizable substances Qualified Qualified
5 Test
5.1 Warning
Some of the reagents which are used in this test method are toxic or
corrosive; therefore, some test procedures may cause dangerous
conditions, and the operator shall take appropriate safety and health
measures.
5.2 General provisions
Unless otherwise specified in this chapter, all the used standard titration
solutions, standard solutions, preparations and products are prepared in
accordance with the provisions of GB/T 601, GB/T 602, GB/T 603; the
experimental water shall meet the specifications of grade-III water in GB/T 6682;
the samples are weighed to the nearest 0.01 g; the used solutions which are
expressed in "%" are all mass fractions.
5.3 Content
5.3.1 Preparation of preparations
5.3.1.1 Preparation of sodium periodate solution
Weigh 60 g of sodium periodate; put it in a beaker; add 120 mL of sulfuric acid
standard titration solution [c( H2SO4) = 0.1 mol/L] and a small amount of water
to dissolve; do not heat during dissolution. If the solution is not clear, use a sand
funnel to filter (do not use the filter paper to filter); transfer the solution to a 1
000 mL volumetric flask; dilute to the mark.
5.3.1.2 Preparation of neutral ethylene glycol solution
Take 50 mL of ethylene glycol to mix with 50 mL of water; add 5 drops of
bromothymol blue indicator solution (1 g/L); use sodium hydroxide standard
titration solution [c(NaOH) = 0.05 mol/L] to titrate until the solution becomes
pure blue. Prepare before use.
5.3.2 Determination
Weigh 0.35 g of sample; accurate to 0.000 1 g; put it in a conical flask with a
stopper; dilute it to 50 mL. Add 5 drops of bromothymol blue indicator solution
(1 g/L); the solution shall be green or yellow-green; if the solution is blue-green,
[c(NaOH) = 0.02 mol/L] to titrate until the solution becomes pure blue; keep it
for 30 s. Add 30 g (24 mL) of sample; shake well; if the solution is yellow, use
sodium hydroxide standard titration solution [c(NaOH) = 0.02 mol/L] to titrate
until the solution becomes pure blue; keep it for 30 s. Calculate the result
according to the provisions of 5.1.2 in GB/T 9736-2008.
5.7 Alkalinity
Take 100 mL of carbon dioxide-free water; add 3 drops of bromothymol blue
indicator solution (1 g/L); use sodium hydroxide standard titration solution
[c(NaOH) = 0.02 mol/L] to titrate until the solution becomes pure blue; keep it
for 30 s. Add 30 g (24 mL) of sample; shake well; if the solution is pure blue,
use hydrochloric acid standard titration solution [c(HCl) = 0.02 mol/L] to titrate
until the solution becomes yellow; keep it for 30 s. Calculate the result according
to the provisions of 5.1.2 in GB/T 9736-2008.
5.8 Chloride
5.8.1 Preparation of test solutions
Weigh 62.5 g (50 mL) of sample; dissolve in water; dilute to 100 mL.
5.8.2 Determination
Take 8 mL of the test solution; measure according to the provisions of GB/T
9729; shake well. The turbidity of the solution shall not be greater than the
standard turbidity solution.
The standard turbidity solution is prepared by taking the standard solution that
contains the following amount of chloride:
Analytical pure…...0.005 mg Cl;
Chemical pure...0.050 mg Cl.
Dilute to 8 mL; treat as the test solution of the same volume at the same time.
5.9 Sulfate
Take 8 mL of the test solution (5.8.1); add 5 mL of methanol; dilute to 20 mL;
add 0.5 mL of hydrochloric acid solution (20%) to acidify; measure according to
GB/T 9728. The turbidity of the solution shall not be greater than the standard
turbidity solution.
The standard turbidity solution is prepared by taking the standard solution that
contains the following amount of sulfate:
Analytical pure…...0.025 mg SO4;
M -- the numerical value of the molar mass of tributyl glyceride, in grams per
mole (g/mol) [M( C15H26O6) = 100.8];
m -- the value of sample mass, in grams (g).
5.15 Sucrose and glucose
Take 10 mL of the test solution (5.8.1); add 1 mL of sulfuric acid solution (20%);
heat on the water bath for 5 min; add 2 mL of sodium hydroxide solution (100
g/L) and 5 mL of Fehring’s solution; then, heat for 10 min. The solution must not
appear cloudy or precipitate.
5.16 Substances that reduce silver
5.16.1 Warning
The silver-ammonia mixed solution is explosive and shall be discarded
after use.
5.16.2 Determination
Weigh 5 g (4 mL) of the sample; add 5 mL of ammonia solution (5%); shake
well; heat to 60 °C in a water bath; add 0.5 mL of silver nitrate solution (17 g/L);
shake well; place in a dark place for 5 min. The dark color of the solution must
not be darker than the color of the same amount of sample that is treated
without the addition of silver nitrate solution.
5.17 Readily carbonizable substances
Weigh 6.25 g (5 mL) of the sample; add 5 mL of sulfuric acid (guaranteed
reagent, 95% ± 0.5%) dropwise when stirring. At this time, the temperature shall
not exceed 50 °C. Leave for 30 min. The color of the solution must not be darker
than the standard color F or P that is specified in GB/T 9737.
6 Inspection rules
Perform sampling and acceptance according to HG/T 3921.
7 Packaging and marking
Perform packing, storage and transportation according to the provisions of GB
15346; give signs, of which:
Packaging unit: category 4;
......
Source: Above contents are excerpted from the PDF -- translated/reviewed by: www.chinesestandard.net / Wayne Zheng et al.
|