GB/T 4103.6-2000 Chemical analysis methods for lead and lead alloys - Determination of arsenic content
Some standard content:
GB/T 4103.6-2000
This standard is a revision of GB/T4103.9-1983 "Chemical analysis method for lead-based alloys: Molybdenum blue photometric method for determination of arsenic content GJB/T472.4 Silver diethyldithiocarbamate spectrophotometric method for determination of arsenic content": 1984 "Chemical analysis method for lead ingots
This standard complies with:
GB/T1.1--1993 Guidelines for standardization work
Basic provisions
Unit 1: Drafting and presentation of standards Part 1: GB/T1.4-1988 Guidelines for Standardization Work Provisions for the Preparation of Chemical Analysis Methods GB/T1467-1978 General Principles and General Provisions for Chemical Analysis Methods for Metallurgical Products GB/T7729-1987 General Principles for Spectrophotometric Methods for Chemical Analysis of Metallurgical Products GB/T17433-1998 Basic Terminology for Chemical Analysis of Metallurgical Products This standard replaces GB/T4103.9-1983 and GB/T472.4-1984 from the date of entry into force. This standard is proposed by the State Bureau of Nonferrous Metals Industry. This standard is under the jurisdiction of the China Nonferrous Metals Industry Standards and Metrology Quality Research Institute. Shenyang Smelter and Northwest Copper Processing Plant of Baiyin Nonferrous Metals Company are responsible for drafting this standard. This standard is drafted by Shenyang Smelter.
Main drafters of this standard: Liu Guohong, Zhang Quan12
1 Scope
National Standard of the People's Republic of China
Chemical analysis methods of lead and lead alloys
Determination of arsenic content
Methods for chemical analysis of lead and lead alloysDetermination of arsenic content This standard specifies the determination method of arsenic content in lead and lead alloys. GB/T 4103.62000
Replaces GB/T4103.G
GB/R 472. - --198
This standard is applicable to the determination of arsenic content in lead and lead alloys. Determination range: 0.00030%~0.30%. 2 Summary of the method
The sample is dissolved in sulfuric acid, the matrix lead is separated in the form of lead sulfate precipitation, and the lead ingot is directly colored for spectrophotometric determination. Lead and gold are extracted in a medium of 9 mol/L hydrochloric acid (HCl). Lead and high content of antimony and tin are extracted with lysine. A mixed display agent and ascorbic acid are added to form an arsenic bismuth molybdenum blue complex. The absorbance is measured at a wavelength of 730 nm on a spectrophotometer. 3 Reagents
3.1 Potassium sulfate.
3.2 Benzene.
3.3 Hydrochloric acid (pl.19).
3.4 Sulfuric acid (ol.84)
3.5 Nitric acid (l.42).
3.6 Sulfuric acid (1+1).
Fluorine water (1+1).
3.8 Sulfuric acid (1+9).
3.9 Hydrochloric acid (3+-1).
3.10 Phenolphthalein solution (2 mmol/L).
3.11 Potassium permanganate solution (20g/L). 3.12
Ascorbic acid solution (20g/L).
3 Reducing agent: 4g/L sodium bisulfite solution, mixed with 0.4g/L sodium thiosulfate in equal volumes. 3.13
Potassium sulfate solution: weigh 2g potassium sulfate and dissolve it in water, add 20ml sulfuric acid (3.4), and dilute it to 100ml with water. 3.14#
3.15 Mixed color developer: weigh 30g ammonium tartrate and dissolve it in 300mL water, 50g potassium sodium tartrate and dissolve it in 300ml water, and combine the two phases after dissolution. Weigh 4g of bismuth nitrate and dissolve it in 250mL of sulfuric acid (3.6). After combining the above solutions, dilute with water to 1000ml3.16 arsenic standard stock solution. Weigh 0.1321g of arsenic trioxide (reference reagent) and place it in a 300mL beaker. Add 10ml of sodium hydroxide (50g/1.) to dissolve it. Add 2 drops of phenolphthalein bath solution (3.10) and neutralize with sulfuric acid (3.6) until there is no color selection. Excess 2ml. Transfer to a 1000ml volumetric flask, dilute to the mark with water, and mix well. 1mL of this solution contains 100ug arsenic. 3.17 Standard arsenic solution: Pipette 25.00ml of standard arsenic storage solution (3.16) into a 500ml container. Dilute to scale with water. Approved by the State Administration of Quality and Technical Supervision on 2000-08-28 126
2000.1201 Implementation
Mix well, 1mL of this solution contains 5μg phosphorus.
4 Instruments
Spectrophotometer.
5 Analysis steps
5.1 Test material.
Weigh the sample according to Table 1, accurate to 0.0001g. Arsenic content,%
0. 000 30 ~- 0. 001 5bzxz.net
(0. 001 5 ~~0. 004 0
0. 004 0--0. 015
>0.015~0.070
>0. 070~0. 30
GB/T 4103. 6---2000
Sample amount·
Carry out 2 independent determinations and take the average value. 5.2 Blank test
Carry out a blank test with the sample.
5.3 Determination
Total volume of solution, ml
Transfer volume of solution, ml.
5.3.1 Place the sample (5.1) in a 250ml beaker, add 1g potassium sulfate and 10mL sulfuric acid (3.4), heat to dissolve, remove and cool. 5.3.2 Transfer the test solution (5.3.1) into the volumetric flask shown in Table 1, dilute to the scale, and mix well. 5.3.3 After transferring the test solution according to Table 1, dilute the lead ingot test solution according to 5.3.3.1 The lead alloy test solution shall be carried out according to 5.3.3.2 to 5.3.3.6. 5.3.3.1 Place the lead ingot test solution in a 250ml beaker, steam until the smoke is gone, remove, wash Table III and the wall of the beaker, heat to dissolve the salts. Remove and cool. Add 3 drops of phenolic acid solution, adjust with ammonia water until red appears, and then adjust with sulfuric acid (3.8) until the red disappears. 5.3.3.2 After transferring the test solution according to Table 1, the lead alloy test solution with a volume of less than 10mL shall be supplemented to about 10mL; if it is more than 10mL, it needs to be steamed to about 10ml, remove and cool. Rinse the beaker with 30ml hydrochloric acid (3.3) in several times in a 125mL separatory funnel, add 2ml of reducing agent, mix well, and place for 10 min.
5.3.3.3 Add 20mL of sodium sulfate, shake for 1.5min, let stand to separate the layers, put the aqueous phase into another separatory funnel, add 20ml of benzene, shake for 1 min, let stand to separate the layers, and discard the aqueous phase.
5.3.3.4 Combine the organic phases, use 3-5mL of hydrochloric acid (3.9) each time, rinse the inner wall of the separatory funnel 2-3 times in batches until the organic phase is no longer yellow, and discard the rinse solution.
5.3.3.5 Add 20ml of water to the organic phase, shake for 1min, put the aqueous phase into a 250mL beaker, add 20ml of water and repeat once, combine the aqueous phases
5.3.3.6 Add 5mL of potassium sulfate solution and 5 drops of nitric acid, heat and evaporate until the smoke is removed, and wash the surface boron and beaker with water 5.3.4 Transfer the solution (5.3.3.1 or 5.3.3.6) to a 50mL volumetric flask, add 2 drops of potassium permanganate solution, 5.0mL of mixed color developer, 5.0mL of ascorbic acid solution, dilute to scale with water, mix well, and place for 20 minutes. 5.3.5 Transfer part of the solution (5.3.4) to a 3cm absorption dish, use the blank test solution accompanying the sample as a reference, and measure its absorbance at a wavelength of 730nm on a spectrophotometer. Find the corresponding amount from the working curve. 5.4 Drawing of working curve
5.4.1 Drawing of arsenic working curve of lead ingot
5.4.1.1 Take 0, 1.00, 2.00. 4.00. 6.00. 8.00mL of arsenic standard solution and place them in a group of 50mL volumetric flasks 4. Control the volume to about 10ml, add 2 drops of potassium permanganate solution, add 5mL of mixed color developer, 5ml. Ascorbic acid solution, dilute to scale with water, mix well, and let stand for 20min.
5.4.1.2 Transfer part of the solution (5.4.1.1) into 3cm absorption III, use the reagent blank as reference, and measure its absorbance at a wavelength of 730nm on a spectrophotometer. Draw the working curve with the amount of arsenic as the horizontal axis and the absorbance as the vertical axis. 5.4.2 Lead alloy medium working curve
5.4.2.1 Transfer 0, 2.00. 4.00. 8.00. 12.00, 16.00ml. The standard solution is placed in a 125ml. separating funnel, and the volume is controlled at 10mL. 30ml hydrochloric acid (3.3) is added, 2ml reducing agent is added, mixed, and placed for 10min. The following is carried out according to 5.3.3.3~5.3.3.6.
5.4.2.2 Transfer part of the solution (5.4.2.1) into a 3cm absorption III, and measure its absorbance at a wavelength of 730nm on a spectrophotometer with the reagent blank as a reference. Draw a working curve with the amount of arsenic as the horizontal axis and the absorbance as the vertical axis. Expression of analysis results
Calculate the percentage of arsenic according to Wu (1):
KmV× 10
As(%) =4
Wherein: K
Correction coefficient of lead sulfate precipitation to solution volume in 50mL volumetric flask [0.976 for sample volume 5.0000g: 0.991 for 2.000g; 0.995 for 1.0000g (pPbS0,=6.2g/ml)]: the amount of lead sulfate precipitate obtained from the working curve, ug; V.--total volume of test solution, mL;
V.--volume of test solution taken, mL
ma mass of test sample, g;
The result is expressed to two decimal places; if the arsenic content is less than 0.10%, it is expressed to three decimal places: less than 0.010%, it is expressed to four decimal places; less than 0.0010%, it is expressed to five decimal places. 7 Allowable difference
The difference between the analysis results of laboratories should not be greater than the allowable difference listed in Table 2. Table 2
0. 000 30~0. 000 60
> 0. 000 60 ~ 0. 002 0
0. 002 0~0. 005 0
0. 005 0~0. 010
>0.010~0. 050
>0. 050~~0. 10
0. 10~0. 30
allowable difference
Tip: This standard content only shows part of the intercepted content of the complete standard. If you need the complete standard, please go to the top to download the complete standard document for free.