GB/T 1282-2013 English PDF (GBT1282-2013)

This Standard specifies shape, specification, test, inspection rules, packaging as well as marks for chemical reagent - phosphoric acid. This Standard is applicable to inspection of chemical reagent - phosphoric acid.

GB/T 1282-2013
NATIONAL STANDARD OF THE
PEOPLE’S REPUBLIC OF CHINA
ICS 71.040.30
G 62
Replacing GB/T 1282-1996
Chemical reagent - Phosphoric acid
(ISO 6353-2:1983, Reagents for chemical analysis -
Part 2: Specifications - First series, NEQ)
ISSUED ON: DECEMBER 31, 2013
IMPLEMENTED ON: AUGUST 01, 2014
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 ... 5
2 Normative references ... 5
3 Shape ... 6
4 Specification ... 6
5 Test ... 7
6 Inspection rules ... 12
7 Packaging and marks ... 12
Annex A (Informative) Pressurized ion exchange device ... 14
Foreword
This Standard was drafted in accordance with the rules given in GB/T 1.1-2009. This Standard replaces GB/T 1282-1996 “Chemical reagent - Phosphoric acid”. Compared with GB/T 1282-1996, main technical changes are as follows:
-- modified unit of volatile acid from “mmol/100g” to “mmol/g” (see Clause 4 of this Edition, Clause 4 of Edition 1996);
-- increased specification of arsenic guaranteed reagent, analytical reagent from “0.0001%” to “0.00005%”; raised chemical pure specification from
“0.0005%” to “0.0001%” (see Clause 4 of this Edition, Edition 4 of Edition 1996);
-- increased specification of guaranteed reagent of sodium, potassium, nickel, copper, zinc, cadmium (see Clause 4 of this Edition, Edition 4 of Edition 1996);
-- added specification of analytical reagent and chemical pure of sodium, potassium, nickel, copper, zinc, cadmium, lead (see Clause 4 of this
Edition);
-- increased specification of chemical pure of reducing substance from
“0.05%” to “0.03%” (see Clause 4 of this Edition, Edition 4 of Edition 1996); -- improved determination method for content (see 5.2 of this Edition, 5.1 of Edition 1996);
-- added determination method for arsenic (see 5.8.2);
-- added determination method of inductively coupled plasma atomic
emission spectrometry of sodium, potassium, manganese, nickel, copper,
zinc, cadmium and lead (see 5.10.2);
-- improved pressurized ion exchange device (see Annex A of this Edition, Annex A of Edition 1996);
-- deleted specification and determination methods for burning residue, heavy metal (see Clause 4, 5.3 and 5.12 of Edition 1996);
-- deleted chemical analysis determination method for manganese (see 5.11 of Edition 1996).
This Standard uses redrafting method to modify and adopt R22 "phosphoric acid" in ISO 6353-2:1983 “Reagents for Chemical Analysis -- Part 2:
Chemical reagent - Phosphoric acid
Warning - Some test procedures specified in this Standard may result in dangerous conditions. Users are responsible for taking appropriate
safety and health measures.
Molecular formula: H3PO4
Relative molecular mass: 98.00 (according to 2007 international relative atomic mass)
1 Scope
This Standard specifies shape, specification, test, inspection rules, packaging as well as marks for chemical reagent - phosphoric acid.
This Standard is applicable to inspection of chemical reagent - phosphoric acid. 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 601, Chemical reagent - Preparations of reference titration solutions GB/T 602, Chemical reagent - Preparations of standard solutions for impurity GB/T 603, Chemical reagent - Preparations of reagent solutions for use in test methods
GB/T 605, Chemical reagent - General method for the measurement of
colour
GB/T 610-2008, Chemical Reagent - General Method for the Determination
of Arsenic
GB/T 6682, Water for laboratory use - Specifications
GB/T 9723-2007, Chemical Reagent - General Rule for Flame Atomic
Absorption Spectrometry Analysis
GB/T 9728, Chemical reagent - General method for the determination of
5.5 Chloride
Weigh 5g (3mL) of sample. Dilute to 20mL. Determine according to provisions of GB/T 9729. Solution turbidity shall not be greater than standard turbidity solution.
Preparation of standard turbidity solution takes chloride (Cl) standard solution that contains following quantities. Perform same processing with sample simultaneously.
Guaranteed reagent: 0.010mg; analytical reagent: 0.015mg; chemical pure: 0.025mg.
5.6 Sulfate
Weigh 5g (3mL) of sample. Dilute to 50mL. Take 10mL (5mL for chemical pure). Dilute to 20mL. Add 0.5mL of hydrochloric acid solution (20%). Determine according to provisions of GB/T 9728. Solution turbidity shall not be greater than standard turbidity solution.
Preparation of standard turbidity solution takes sulfate (SO4) standard solution that contains following quantities. Dilute to 20mL. Perform same processing with same volume of sample solution simultaneously.
Guaranteed reagent: 0.01mg; analytical reagent: 0.03mg; chemical pure:
0.05mg.
5.7 Nitrate
Weigh 5g (3mL) of sample. Dilute to 10mL. Add 1mL of sodium chloride solution (100g/L) and 1mL of indigo sodium disulphonate solution
[c(C16H8N2Na2O8S2)=0.001 mol/L]. While shaking, within 10s~15s, add 10mL of sulfuric acid. Place for 10min. Blue of solution shall not be lighter than standard colorimetric solution.
Preparation of standard colorimetric solution takes nitrate (NO3) standard solution that contains following quantities. Perform same processing with sample simultaneously.
Guaranteed reagent: 0.015mg; analytical reagent, chemical pure: 0.025mg. 5.8 Arsenic
5.8.1 Silver diethyldithiocarbamate method (arbitration method)
Weigh 4g (2.4mL) of sample. Dilute to 30mL. Inject into arsenic bottle. Determine according to provisions of 4.2 in GB/T 610-2008. Purple red of absorbent shall not be darker than standard colorimetric solution.
5.10.1.3 Preparation of test solution
See Annex A for pressurized ion exchange device. Ion exchange column is loaded with strong acid cation exchange resin of which particle diameter is 0.04mm~0.08mm, and exchange capacity is 4mmol/g~5mmol/g. When
exchanged, flow rate is controlled at 1.0mL/min ~ 1.5mL/min.
Weigh 10g (6mL) of sample. Place in a 25mL volumetric flask. Dilute to scale. Mix well. Open exchanger rubber plug. Inject 5mL of sample into exchanger. Tighten rubber plug. Pressurize exchanger (less than 0.1MPa). Phosphoric acid matrix flows out from lower end of exchanger and is discarded. Open exchanger rubber plug. Add 5mL of water. Re-pressurize remaining sample in washing exchanger and discard it.
Open exchanger rubber plug. Add 5mL of hydrochloric acid solution (10%). Tighten rubber plug. Pressurize exchanger (less than 0.1MPa). Receive eluent in a cleaned container. Add 5mL of water into exchanger. Pressurize washing exchanger. Combine washing solution and eluent, as test solution.
5.10.1.4 Determination methods
5.10.1.4.1 Sodium
Take 1mL of test solution. Dilute to 250mL. Determine according to provisions of 7.2.1 in GB/T 9723-2007. Calculate result according to provisions of 7.2.3. 5.10.1.4.2 Potassium, zinc
Take 1mL of test solution. Dilute to 10mL. Respectively determine according to provisions of 7.2.1 in GB/T 9723-2007. Calculate result according to provisions of 7.2.3.
5.10.1.4.3 Manganese, lead
Take test solution. Respectively determine according to provisions of 7.2.1 in GB/T 9723-2007. Calculate result according to provisions of 7.2.3.
5.10.1.4.4 Nickel, copper, cadmium
Take 4mL of test solution. Dilute to 10mL. Respectively determine according to provisions of 7.2.1 in GB/T 9723-2007. Calculate result according to provisions of 7.2.3.
5.10.2 Inductively coupled plasma atomic emission spectrometry
5.10.2.1 Reagent, material and apparatus
In accordance with provisions of Clause 5, Clause 6 in GB/T 23942-2009. {c[Ce(SO4)2]=0.1mol/L} and 10mL of silver sulfate solution (10g/L). Add 40mL of water. Boil 15min. Cool. Dilute to original volume. Add 2 drops of 1,10- phenanthroline-ferrous iron indicator solution. Use ammonium ferrous sulfate standard titration solution {c[(NH4)2Fe(SO4)2]=0.1mol/L} to titrate till solution is red. Carry out blank test at the same time.
Calculate mass fraction (w2) of reducing substance (in H3PO3) according to formula (2):
Where,
V1 - Value of volume of ammonium ferrous sulfate standard titration solution consumed by blank test, in milliliters (mL);
V2 - Value of volume of ammonium ferrous sulfate standard titration solution, in milliliters (mL);
c - Accurate value of concentration of ammonium ferrous sulfate standard titration solution, in Moore per liter (mol/L);
M - Value of molar mass of phosphorous, in grams per Moore (g/mol) [M
(1/2H3PO3)=41.00];
m - Value of sample mass, in grams (g).
6 Inspection rules
Perform sampling and acceptance according to provisions of HG/T 3921.
7 Packaging and marks
Perform packaging, storage and transport according to provisions of GB 15346. Provide marks, where:
Packaging unit: category 4, category 5;
Inner packaging pattern: NB-20, NB-21, NB-26, NB-27, NB-29;
Isolation material: GC-2, GC-3;
External packaging pattern: WB-1, WB-3;