US$449.00 · In stock
Delivery: <= 4 days. True-PDF full-copy in English will be manually translated and delivered via email.
GB 28657-2012: [GB/T 28657-2012] Potassium dichromate for industrial use
Status: Valid
| Standard ID | USD | BUY PDF | Lead-Days | Standard Title (Description) | Status |
| GB 28657-2012 | 449 |
Add to Cart
|
4 days
|
[GB/T 28657-2012] Potassium dichromate for industrial use
| Valid |
Basic data
Standard ID: GB 28657-2012 (GB28657-2012)
Description (Translated English): [GB/T 28657-2012] Potassium dichromate for industrial use
Sector / Industry: National Standard
Classification of Chinese Standard: G12
Classification of International Standard: 71.060.50
Word Count Estimation: 17,130
Quoted Standard: GB 190-2009; GB/T 191-2008; GB/T 6678; GB/T 6682-2008; GB/T 8170; GB 12463-2009; HG/T 3696.1-2002; HG/T 3696.2; HG/T 3696.3
Regulation (derived from): National Standards Bulletin No. 24 of 2012
Issuing agency(ies): General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China, Standardization Administration of the People's Republic of China
Summary: This Chinese standard specifies the requirements for industrial potassium dichromate, test methods, inspection rules, as well as marking, labeling, packaging, transportation, storage, and security. This standard applies primarily as a production of potass
GB 28657-2012: [GB/T 28657-2012] Potassium dichromate for industrial use
---This is a DRAFT version for illustration, not a final translation. Full copy of true-PDF in English version (including equations, symbols, images, flow-chart, tables, and figures etc.) will be manually/carefully translated upon your order.
Potassium dichromate for industrial use
ICS 71.060.50
G12
National Standards of People's Republic of China
Industrial potassium dichromate
Published 2012-09-03
2013-06-01 implementation
Administration of Quality Supervision, Inspection and Quarantine of People's Republic of China
Standardization Administration of China issued
Foreword
This standard Chapter 7, Chapter 8 8.1,8.3,8.4, Chapter 9 is mandatory, the rest are recommended.
According to the rules of drafting this standard GB/T 1.1-2009 given.
This standard ГΟСТ2652. 1978 "Industrial dichromate technical conditions" (Russian) technical differences and structural differences see
Appendix A and Appendix B.
The standard proposed by China Petroleum and Chemical Industry Federation.
This standard by the National Standardization Technical Committee chemical inorganic chemicals branch (SAC/TC63/SC1).
This standard is mainly drafted by. CNOOC Tianjin Chemical Research & Design Institute, Sichuan Anxian Yinhe built of (Group) Co., Ltd.
The main drafters of this standard. Li Xia, Li Xianrong, ZHAO Jian, Yang Yan, Li Xiaofeng.
This standard supersedes the previous editions are.
--- GB 1609-1979, HG/T 2324-1992, HG/T 2324-2005.
Industrial potassium dichromate
1 Scope
This standard specifies the requirements, test methods, inspection rules, marking, labeling, packaging, transportation, storage and security industry potassium dichromate.
This standard applies to industrial production mainly as chromium potassium sulfate, chromium oxide, chrome yellow pigment, potassium, matches, enamels, welding electrodes feedstock
Potassium dichromate.
2 Normative references
The following documents for the application of this document is essential. For dated references, only applies to the version dated paper
Pieces. For undated references, the latest edition (including any amendments) applies to this document.
GB 190-2009 dangerous goods packaging logo
GB/T 191-2008 Packaging Pictorial signs
GB/T 6678 General Principles for Sampling Chemical Products
GB/T 6682-2008 specifications and test methods for water analysis laboratory
GB/T 8170 rounding off means about rules and determining limiting values
GB 12463-2009 transport of dangerous goods packaging technology
Preparation HG/T 3696.1-2002 Inorganic chemicals for chemical analysis of standard titration solution
Preparation HG/T 3696.2 Inorganic chemicals solution used for chemical analysis of standard impurities
Preparations with HG/T 3696.3 Inorganic chemicals Chemical Analysis
Molecular formula and molecular weight 3
Molecular formula. K2Cr2O7
Molecular weight. 294.18 (according to 2007 international relative atomic mass)
4 Requirements
4.1 Appearance. bright orange-red needles or small granular crystals.
4.2 Potassium dichromate industry should meet the requirements of Table 1.
Table 1
project
index
Premium grade First grade Qualified
Potassium dichromate (K2Cr2O7 in terms) w /% ≥ 99.8 99.5 99.0
Sulfate (in terms of SO4) w /% ≤ 0.02 0.05 0.05
Chloride (based on Cl) w /% ≤ 0.03 0.05 0.07
Sodium (Na) w /% ≤ 0.4 1.0 1.5
Moisture w /% ≤ 0.03 0.05 0.05
Water insoluble matter w /% ≤ 0.01 0.02 0.05
5 Test methods
5.1 Safety Tips
Reagents used in this test method are toxic, corrosive, the operator should be careful as splashed on the skin should be washed with water immediately
Wash, severe cases should seek medical care immediately. When using flammable materials, it prohibited the use of open flame heating.
5.2 General Provisions
This standard reagent in the absence of water and other requirements stated, refer to three predetermined analytical reagents and GB/T 6682-2008 of
water. The test standard titration solution, impurity standard solution, formulations and products, in the absence of other requirements specified, are by HG/T 3696.1 used,
HG/T 3696.2, preparing a predetermined HG/T 3696.3 is.
5.3 Visual inspection
In natural light, the appearance was visually determined.
5.4 Determination of the content of potassium dichromate
5.4.1 Capacity Act (Arbitration Act)
5.4.1.1 Method summary
In an acidic medium, hexavalent chromium ions to divalent iron ions in the sample oxidation-reduction reaction, to phthalic acid as indicated
Agent titrated solution was titrated to standard ferrous ammonium sulfate solution turned green.
5.4.1.2 Reagents
5.4.1.2.1 phosphoric acid.
5.4.1.2.2 sulfuric acid. 14.
5.4.1.2.3 standard ferrous ammonium sulfate titration solution. c [(NH4) 2Fe (SO4) 2] ≈0.2mol/L.
Preparation. Weigh about 80g of ferrous ammonium sulfate [(NH4) 2Fe (SO4) · 6H2O] was dissolved in 300mL sulfuric acid solution (17), followed by addition
700mL of water, shake. This calibration solution before use.
Calibration. Weigh about 0.37g finely and at 120 ℃ ± 2 ℃ dried to a constant reference mass of potassium dichromate, accurate to 0.0001g,
Placed in 500mL Erlenmeyer flask, 150mL of water was added to dissolve. Was added a solution of 15mL sulfuric acid, phosphoric acid 5 mL, dropwise with standard ferrous ammonium sulfate
Given solution was titrated to yellow-green solution. O-aminobenzoic acid was added 1mL indicator solution and continue the titration to the solution from purple to green
As the end point.
Concentration of ammonium ferrous sulfate standard titration solution C, the value in mol/L, calculated according to formula (1).
c = mMV × 10-3
(1)
Where.
Numerical volume standard titration solution of ammonium ferrous sulfate titration V --- consumed in milliliters (mL);
--- potassium dichromate reference value of mass m in grams (G);
M --- potassium dichromate (16K2Cr2O7
) Molar mass values, in units of grams per mole (g/mol) (M = 49.03).
Calibration errors shall HG/T 3696.1-2002 specified in 3.6, 3.7.
5.4.1.2.4 o-aminobenzoic acid indicator solution. 1g/L.
5.4.1.3 apparatus, equipment
5.4.1.3.1 weighing bottle. φ50mm × 30mm.
5.4.1.3.2 electric oven. temperature can be controlled at 120 ℃ ± 2 ℃.
5.4.1.4 Analysis of step
A test solution is prepared 5.4.1.4.1
Weigh 4.99g ~ 5.01g sample, accurate to 0.0001g, was placed in a 150mL beaker, add water dissolved, transferred to 500mL volume
Volumetric flask, diluted with water to the mark. This solution is a test solution A, for the content of potassium dichromate, sulfate content (visual turbidimetry) and
Determination of sodium content.
5.4.1.4.2 Determination
Pipette with a pipette 25mL of test solution A, placed in 500mL Erlenmeyer flask, was added 150mL of water, 15 mL of sulfuric acid solution, 5 mL
Phosphoric acid solution was titrated to titration with standard ferrous ammonium sulfate solution was yellow-green. O-aminobenzoic acid was added 1mL indicator solution and continue the titration
To the solution from purple to green as the end point.
5.4.2 potentiometric titration
5.4.2.1 Method summary
The sample was dissolved in water, in acidic medium, titrated with standard ferrous ammonium sulfate solution was titrated to the maximum rate of potential change point determination trans
It should end, obtained potassium dichromate content.
5.4.2.2 Reagents
5.4.2.2.1 sulfuric acid. 11.
5.4.2.2.2 standard ferrous ammonium sulfate titration solution. c [(NH4) 2Fe (SO4) 2] ≈0.2mol/L.
Calibration. Weigh about 0.37g finely and at 120 ℃ ± 2 ℃ dried to a constant reference mass of potassium dichromate, accurate to 0.0001g,
It was placed in 500mL beaker, add water to 400 mL, was added a solution of 40mL sulfuric acid. The beaker was placed on a magnetic stirrer. Insert platinum electrode
Electrode and a saturated calomel electrode, and stirring, stirring speed control solution to avoid splashing. Titration solution was titrated with standard ferrous ammonium sulfate to a yellow
After the disappearance, continued microtiter. The point of maximum potential rate of change is the endpoint of the titration.
Calculation. calculated in 5.4.1.2.3.
5.4.2.3 apparatus, equipment
5.4.2.3.1 magnetic stirrer.
5.4.2.3.2 indicator electrode. platinum electrode.
5.4.2.3.3 reference electrode. saturated calomel electrode.
5.4.2.3.4 automatic potentiometric titrator.
5.4.2.4 Analysis of step
Pipette with a pipette 25mL of test solution A, was placed in a beaker of 500mL, was added to 400 mL of water, was added a solution of 40mL sulfuric acid.
The beaker was placed on a magnetic stirrer. Insert platinum electrode and a saturated calomel electrode, and stirring, stirring speed control solution to avoid splashing. use
After standard ferrous ammonium sulfate solution was titrated to the yellow color disappeared titration, the microtiter continued, the potential of the point of maximum rate of change is the titration end point.
5.4.3 calculation results
Potassium dichromate potassium dichromate content mass (of K2Cr2O7) fraction w1 meter, calculated according to formula (2).
w1 = cVM × 10
-3
m × (25/500) × 100%
(2)
Where.
Numerical standard titration solution of ammonium ferrous sulfate V --- volume of the test solution consumed in the titration, in milliliters (mL);
C --- accurate value of the concentration of the solution of ferrous ammonium sulfate titration standard, in units of moles per liter (mol/L);
m --- 5.4.1.4.1 weighed mass of the sample values in grams (G);
M --- potassium dichromate (16K2Cr2O7
) Molar mass values, in units of grams per mole (g/mol) (M = 49.03).
Parallel to the arithmetic average of the measurement results of the measurement result, the absolute difference determination results should not exceed 0.2% in parallel.
5.5 Determination of the sulfate content
5.5.1 gravimetric method (MAL)
5.5.1.1 Method summary
In an acidic medium, with ethanol in the sample and reduction of Cr 6 Cr 3, was added a solution of barium chloride, barium sulfate ions in the raw sample
To precipitate barium sulfate. The precipitate was filtered, washed, calcined and weighed to determine sulphate content was calculated.
5.5.1.2 Reagents
5.5.1.2.1 sulfuric acid.
5.5.1.2.2 95% ethanol.
5.5.1.2.3 hydrochloric acid solution. 37.
5.5.1.2.4 acetic acid solution. 11.
5.5.1.2.5 barium chloride (BaCl2 · 2H2O) solution. 100g/L.
5.5.1.2.6 silver nitrate solution. 17g/L.
5.5.1.2.7 sulfate standard solution. 1mL solution containing sulfate (SO4) 1mg.
5.5.1.2.8 diphenyl carbohydrazide azo indicator solution. 2g/L.
Azo weighed diphenyl carbohydrazide (C13H12N4O) 0.2g, was dissolved in 50mL of acetone, diluted with water to 100mL, shake, stored in
Brown bottle and stored at a low temperature. After darkening can not be used.
5.5.1.3 apparatus, equipment
Temperature furnace. temperature can be controlled at 700 ℃ ± 20 ℃.
5.5.1.4 Analysis of step
It weighs about 10g sample to the nearest 0.01g. Was placed in 500mL beaker, 100mL of water was added to dissolve. Add 10mL pipette
Sulfate standard solution was added 100mL of hydrochloric acid, heated to about 20mL95% ethanol was added dropwise with stirring, heated in a boiling water bath Paul
Wen 30min. The reduction is not complete, refed with 95% ethanol (with azo-diphenyl carbohydrazide verify complete reduction 1)). Qualitative medium speed
Filter paper, washed with hot water until no green filter. The filtrate and the washing water collected in a 500mL beaker, diluted with water to about 300 mL, heated
boiled. In the micro-boiling state, was added slowly with stirring 50mL barium chloride solution, 20 mL acetic acid solution prepared in advance and set a little
The amount of paper pulp, stir for about 2min. 30min heating on a water bath for 2h at room temperature or placed 8h. Quantitative filter with a slow
A paper filter, washed thoroughly with water until no chloride ions until the (test with silver nitrate solution).
1) Take a drop of test solution 1 was added dropwise diphenyl carbohydrazide azo indicator solution, purple occurs if the restore completely.
The filter paper and the precipitate was placed in a pre calcined at 700 ℃ ± 20 ℃ to constant mass in a porcelain crucible, low temperature ashing in an electric furnace, removed.
After cooling 1 drop of sulfuric acid was heated on a hot plate to take the best white smoke, into 700 ℃ ± 20 ℃ high temperature burning furnace to constant mass.
At the same time a blank test without addition of the sample, the exact same amount of other reagents added to the test solution, and the same treatment and the sample.
5.5.1.5 calculation results
Sulfate content of sulfate (SO4) w2 mass fraction basis, according to equation (3) is calculated.
w2 = 0.4116 ×
(M1-m0)
m × 100%
(3)
Where.
Numerical M1 --- barium sulphate precipitate mass in grams (G);
M0 --- mass of precipitate blank test values in grams (G);
Value m --- mass of the sample in grams (G);
0.4116 --- barium sulfate is converted to sulfate (SO4) coefficients.
Parallel to the arithmetic average of the measurement results of the measurement result, the absolute difference determination results parallel to 0.003%.
5.5.2 Visual turbidimetry
5.5.2.1 Method summary
In an acidic medium, barium sulfate and barium sulfate precipitate plasma generation poorly soluble at low sulfate ion content, within a certain time
Barium sulfate suspension was, the solution was cloudy, for visual comparison with the standard turbidimetric turbidimetric sulfate solution.
5.5.2.2 Reagents
5.5.2.2.1 hydrochloric acid solution. 11.
5.5.2.2.2 barium chloride (BaCl2 · 2H2O) solution. 100g/L.
5.5.2.2.3 sulfate standard solution. 1mL solution containing sulfate (SO4) 0.05mg.
Pipette with a pipette 5mL sulfate standard solution according to HG/T 3696.2 formulated, a 100mL volumetric flask, dilute to
Mark and shake. This solution just before use.
5.5.2.2.4 sulfate-free potassium dichromate solution. 1mL solution containing potassium dichromate (K2Cr2O7) 0.05g.
Industrial weighed 50.0g ± 0.1g potassium dichromate, was placed 500mL beaker was added 300mL of water was dissolved, heated to boiling, was added 2g
Barium chloride, kept boiling for 10min, allowed to stand overnight, the crucible with glass frit (5μm ~ 15μm) suction, and the filtrate into 1000mL volumetric flask
In, diluted with water to the mark.
5.5.2.3 Analysis of step
Pipette with a pipette 25mL of test solution A, a 50mL colorimetric tube, was added 3mL hydrochloric acid, barium chloride is added 5mL
The solution was diluted with water to the mark. 20min ~ 30min incubation in a water bath of 30 ℃ ~ 40 ℃, turbidity should not be greater than standard
Turbid liquid.
Ratio of standard reference suspension prepared. 2 in 50mL colorimetric tube were added with a pipette 5mL sulfate-free solution of potassium dichromate,
Pipetted added 1.00 mL (Excellence), 2.50 mL (first-class products, qualified) sulfate standard solution was added 3mL hydrochloric acid solution, and then
Was added 5mL barium chloride solution, diluted with water to the mark. 20min ~ 30min incubation in a water bath of 30 ℃ ~ 40 ℃.
Assay sulphate content by ion chromatography See Appendix C.
5.6 Determination of chloride content
5.6.1 Capacity Act (Arbitration Act)
5.6.1.1 Method summary
Generating an indication under slightly alkaline conditions, chloride ions in the sample solution a precipitate with silver nitrate, silver chromate micro brick red precipitate
end.
5.6.1.2 Reagents
5.6.1.2.1 saturated sodium carbonate solution.
5.6.1.2.2 standard silver nitrate titration solution. c (AgNO3) ≈0.05mol/L.
Pipette with a pipette 50mL formulated in HG/T 3696.1 specified standard silver nitrate titration solution, 100mL volumetric flask.
Diluted with water to the mark. This standard solution was titrated before use formulation, and stored in a brown bottle.
5.6.1.3 Instruments
Microburette.
5.6.1.4 Analysis of step
Weigh 2.00g ± 0.01g sample is placed in 250mL Erlenmeyer flask, was added 30mL of water to dissolve. Saturated sodium carbonate solution cautiously added dropwise
Solution, until the solution turns yellow, then a pH of 7.5 to 8.0 (with a precision paper test). Then titrated with a standard silver nitrate solution was titrated to dissolve
Liquid was slightly red brick as the end point.
At the same time a blank test, 1.00g ± 0.01g sample is weighed, added to the other reagents identical amount of the test solution, and the sample
The same treatment.
5.6.1.5 calculation results
The chloride content by mass chlorine (Cl) w3 fraction meter, calculated according to formula (4).
w3 = c
(V-V0) M × 10-3
m-m0 ×
100% (4)
Where.
Numerical V --- standard titration solution of silver nitrate titration volume of test solution consumed, in milliliters (mL);
--- blank titration value V0 standard titration solution volume silver nitrate solution consumed in milliliters (mL);
Accurate value of the concentration of the solution c --- standard silver nitrate titration, expressed in moles per liter (mo1/L);
Value m --- mass of the sample in grams (G);
M0 --- blank test mass of the sample values in grams (G);
Numerical molar mass M --- chlorine (Cl), in units of grams per mole (g/mol) (M = 35.45).
The arithmetic average of the measurement results parallel the measurement results, the measurement result of the absolute difference is not greater than two parallel 0.002%.
5.6.2 Ion Chromatography
5.6.2.1 Method summary
After the sample is dissolved, with hydrazine hydrate reduction of hexavalent chromium to trivalent chromium, the precipitate separated was removed, ion implantation chromatograph assay.
5.6.2.2 Reagents
5.6.2.2.1 hydrazine hydrate. 110.
An amount of 10mL hydrazine hydrate (85%) was mixed with 100mL of water.
5.6.2.2.2 chloride standard solution. 1mL solution containing chloride (Cl) 0.05mg;
Pipette with a pipette 5mL chloride standard solution according to HG/T 3696.2 formulated, a 100mL volumetric flask, dilute to
Mark and shake. The solution just before use.
5.6.2.2.3 a water. in line with GB/T 6682-2008 specified.
5.6.2.3 instruments, apparatus 2)
2) The apparatus listed for reference only and configuration, the same configuration can be used, and equipment performance.
5.6.2.3.1 ion chromatography.
5.6.2.3.2 Sample before treatment column. Column hydrogen.
5.6.2.3.3 0.22μm aqueous millipore filter.
5.6.2.3.4 speed centrifuge. with 100mL centrifuge tube.
5.6.2.4 instrument reference conditions
5.6.2.4.1 Column. IonPacAS11-HC250mm × 4mm (IonPacAG11-HC50mm × 4mm with guard column)
Or equivalent person.
5.6.2.4.2 suppressor. ASRSULTRAⅡ, from circulation electric suppress or equivalent person.
5.6.2.4.3 Detector. electric conductivity detector, to confirm if the same function can also be used other detectors.
5.6.2.4.4 eluent. KOH gradient eluent (sparging the initial concentration of 5mmol/L, concentration of the end of 40mmol/L, leaching
Wash time was 40min, elution flow rate of 1.0mL/min). Other types and varying concentrations of the eluent, to confirm if the same work top
Energy can be used.
5.6.2.4.5 Eluent flow rate. 1.0mL/min.
5.6.2.4.6 Injector. 0.025mL.
5.6.2.5 Analysis of step
5.6.2.5.1 work drawing curves
Were pipetted 0mL, 1.00mL, 2.00mL, 4.00mL, 6.00mL, 8.00mL chloride solution was placed in 100mL receiving standard
Volumetric flask, add water to the mark. Solution concentrations were 0mg/mL, 0.0005mg/mL, 0.001mg/mL, 0.002mg /
mL, 0.003mg/mL, 0.004mg/mL, respectively, after this series of standard solution microporous membrane filter of 0.22μm, discard the initial
10mL of the filtrate, the filtrate after the hydrogen directly into the ion chromatograph column. Chloride concentration in abscissa, the peak height or peak a......
Tips & Frequently Asked Questions:
Question 1: How long will the true-PDF of GB 28657-2012_English be delivered?
Answer: Upon your order, we will start to translate GB 28657-2012_English as soon as possible, and keep you informed of the progress. The lead time is typically 2 ~ 4 working days. The lengthier the document the longer the lead time.
Question 2: Can I share the purchased PDF of GB 28657-2012_English with my colleagues?
Answer: Yes. The purchased PDF of GB 28657-2012_English will be deemed to be sold to your employer/organization who actually pays for it, including your colleagues and your employer's intranet.
Question 3: Does the price include tax/VAT?
Answer: Yes. Our tax invoice, downloaded/delivered in 9 seconds, includes all tax/VAT and complies with 100+ countries' tax regulations (tax exempted in 100+ countries) -- See Avoidance of Double Taxation Agreements (DTAs):
List of DTAs signed between Singapore and 100+ countriesQuestion 4: Do you accept my currency other than USD?
Answer: Yes. If you need your currency to be printed on the invoice, please write an email to Sales@ChineseStandard.net. In 2 working-hours, we will create a special link for you to pay in any currencies. Otherwise, follow the normal steps: Add to Cart -- Checkout -- Select your currency to pay.
