Some standard content:
Chemical Industry Standard of the People's Republic of China
Industrial Active Zinc Oxide
1 Subject Content and Scope of Application
HG/T 2572
This standard specifies the technical requirements, test methods, inspection rules, as well as marking, packaging, transportation and storage of industrial active zinc oxide. 94
This standard applies to industrial active zinc oxide obtained by decomposition of zinc carbonate. This product is mainly used as a reinforcing agent for rubber or cables, an activator (natural rubber), and a vulcanizing agent for natural rubber and chlororubber. Molecular formula: ZnO
Relative molecular mass: 81.39 (according to the international relative atomic mass in 1989) Reference standards
Pictorial symbols for packaging, storage and transportation
GB/T 601
GI/T 602
GB/T 603
GB 1250
Chemical reagentsPreparation of standard solutions for titration analysis (volume analysis)Chemical reagents
Preparation of standard solutions for impurity determination
Preparation of preparations and products used in chemical reagent test methodsExpression and determination methods of limit valuesGB/T 2922
GB/T 6678
GB/T 6682
GB 8946
Chemical reagents-Determination method of specific surface area of chromatographic carriers-General rules for sampling of chemical products
Specifications and test methods for water used in analytical laboratories-Plastic woven bags
GB/T 9723
3 Technical requirements
Chemical reagents
General rules for flame atomic absorption spectrometry
Appearance: This product is white or slightly yellow fine powder. 3.1
3.2 Industrial active zinc oxide shall meet the requirements of the following table: Item
Zinc oxide (ZnO)) Basis
Water-soluble matter content
Ignition loss
Hydrochloric acid insoluble matter content
Lead oxide (Pb) content
Manganese oxide (Mn) contentbzxZ.net
First-class product approved by the Ministry of Chemical Industry of the People's Republic of China on February 9, 1994
Qualified product
1~～4
Implementation on July 1, 1994
Copper oxide (Cu) content
Fineness (45um test sieve residue)
Specific surface area, m2/g
Bulk density, g/mL
4 Test method
HG/T 2572
-Qualified products
The reagents and water used in this standard, unless otherwise specified, refer to analytically pure reagents and grade 3 water specified in GB/T6682. The standard titration solutions, impurity standard solutions, preparations and products used in the test, unless otherwise specified, are prepared in accordance with the provisions of GB/T601, GB/T602 and GB/T603. 4.1 Determination of zinc oxide content
4.1.1 Summary of the method
In the test solution, use xylenol orange as an indicator and EDTA standard titration solution to titrate zinc ions. Determine the zinc oxide content based on the consumption of EDTA standard titration solution. 4.1.2 Reagents and materials
Potassium iodide (GB/T1272);
4. 1. 2. 1
Ammonia water (GB/T631);
Hydrochloric acid (GB/T622) solution: 1+1;
Potassium fluoride (GB/T1271) solution: 200g/L; Thiourea (HG/T3-979): saturated solution; Acetic acid-sodium acetate buffer solution: pH=4.5; Disodium ethylenediaminetetraacetic acid (GB/T1401) standard titration solution: c(EDTA)α0.05mol/L; Xylenol orange indicator solution: 2g/L.
4.1.3 Analysis steps
Weigh about 0.12-0.14g of sample (accurate to 0.0002g), place in a 250mL conical flask, add 10ml hydrochloric acid solution, heat to dissolve the sample completely, cool, add 50ml water, 5ml potassium fluoride solution, 5 drops of xylenol orange indicator solution, shake well. Use ammonia water to adjust until the test solution is just red, add 10ml thiourea saturated solution, 20ml acetic acid-sodium acetate buffer solution, 4g potassium iodide, shake well. Titrate with EDTA standard titration solution until the solution is bright yellow, which is the end point. 4.1.4 Expression of analysis results
The content of zinc oxide (ZnO) X expressed as mass percentage is calculated according to formula (1): V: c×0. 081 39 ×100
V---the volume of EDTA standard titration solution consumed by titrating the test solution, mL; where:
——actual concentration of EDTA standard titration solution, mol/L; m
mass of the sample, g;
the mass of zinc oxide expressed in grams equivalent to 1.00mL of disodium ethylenediaminetetraacetic acid standard titration solution (c (EDTA) = 1.000mol/L).
4.1.5 Allowable difference
The arithmetic mean of the parallel determination results is taken as the determination result. The absolute difference of the parallel determination results shall not exceed 0.5%. 4.2 Determination of moisture
4.2.1 Summary of method
HG/T 2572--94
Under certain temperature conditions, dry the sample to constant weight, and determine the moisture content based on the mass reduction of the sample. 4.2.2 Instruments and equipment
4.2.2.1 Weighing bottle: Φ50mrm×25mm; 4.2.2.2 Electric oven: the temperature can be controlled at 105~110℃. 4.2.3 Analysis steps
Use a weighing bottle that has been kept constant at 105~110℃ to weigh about 5g of sample (accurate to 0.0002g), place it in an electric oven, and dry it at 105~~110℃ to constant weight.
4.2.4 Expression of analysis results
In terms of mass percentage The water content X expressed as a fraction is calculated according to formula (2): X2=
Where: ml-
The mass of the sample after drying, g;
-The mass of the sample before drying, g.
4.2.5 Allowable difference
The arithmetic mean of the parallel determination results is taken as the determination result. The absolute difference of the parallel determination results shall not exceed 0.05%. 4.3 Determination of water-soluble content
4.3.1 Method summary
(2))
The sample is dissolved in water, heated, stirred, and filtered, and a certain amount of the filtrate is evaporated and dried to constant weight. The content of water-soluble matter is determined based on the amount of residue after drying.
4.3.2 Instruments and equipment
4.3.2.1 Porcelain evaporating blood: 150mL,
4.3.2.2 Electric oven: The temperature can be controlled at 105~110℃. 4.3.3 Analysis steps
Weigh about 10g of sample (accurate to 0.01g), place it in a 400mL beaker, moisten it with a small amount of water, add 200mL of carbon dioxide-free water, heat and boil for 5min under constant stirring, quickly cool to room temperature, transfer all to a 250mL volumetric flask, dilute to scale with water, and shake well. Dry filter with medium-speed quantitative filter paper, and discard the first 20mL of filtrate. Use a pipette to transfer 100mL of filtrate, place it in a porcelain evaporator III that has been pre-weighed, and evaporate to dryness in a boiling water bath. Transfer it to an electric oven and dry it at 105-110℃ to constant weight. 4.3.4 Expression of analysis results
The water-soluble matter X expressed as mass percentage is calculated according to formula (3): X3:
Where: mt
The mass of the water-soluble matter·g;
The mass of the sample, g.
4.3.5 Allowable difference
m×250
The arithmetic mean of the parallel determination results shall be taken as the determination result. The absolute difference of the nesting of parallel determinations shall not exceed 0.05%. 4.4 Determination of loss on ignition
4.4.1 Summary of method
At high temperature, the sample is burned to constant weight, and the loss on ignition of the sample is determined based on the reduced mass of the sample. 4.4.2 Instruments and equipment
High temperature furnace: The temperature can be controlled at 850±25℃. (3)
4.4.3 Analysis steps
HG/T 2572-94
Weigh about 3g of the sample after moisture determination (accurate to 0.0002g), place it in a porcelain that has been weighed in advance, put it in a high temperature furnace, and burn it to constant weight at 850±25℃.
4.4.4 Expression of analysis results
The ignition loss X expressed as a mass percentage is calculated according to formula (4); X=
wherein m is the mass of the sample after ignition, .;
the mass of the sample, g.
4.4.5 Allowable difference
The arithmetic mean of the parallel determination results is taken as the determination result. The absolute difference of the parallel determination results shall not exceed 0.2%. 4.5 Determination of hydrochloric acid insoluble matter content
4.5.1 Method summary
After the sample is dissolved in hydrochloric acid, it is filtered, washed and dried to constant weight. According to the mass of the insoluble matter, the content of hydrochloric acid insoluble matter is determined. 4.5.2 Reagents and materials
4.5.2.1 Hydrochloric acid (GB/T622) solution: 1+3; 4.5.2.2 Silver nitrate (GB/T670) solution: 17g/L. 4.5.3 Instruments and equipment
High temperature furnace: the temperature can be controlled at 850±25℃. 4.5.4 Analysis steps
Weigh about 10g of sample (accurate to 0.01g), place it in a 400mL beaker, moisten it with a small amount of water, add 200mL of hydrochloric acid solution, heat it to dissolve the sample completely, filter it with medium-speed quantitative filter paper, wash the insoluble matter with water until there is no chloride ion, and check it with silver nitrate solution. Transfer the insoluble matter and the filter paper into a porcelain that has been pre-weighted, incinerate at low temperature, and then transfer it into a high-temperature furnace and burn it to constant weight at 850±25℃. 4.5.5 Expression of analysis results
The hydrochloric acid insoluble matter X expressed as a mass percentage is calculated according to formula (5): Xs-
Where: mi-
The mass of the hydrochloric acid insoluble matter, g;
The mass of the sample, g.
4.5.6 Allowable difference
The arithmetic mean of the parallel determination results is taken as the determination result. The absolute difference of the parallel determination results shall not exceed 0.005%. 4.6 Determination of lead oxide content
4.6.1 Atomic absorption method (arbitration method)
4.6.1.1 Summary of the method
See Article 3 of GB/T9723.
4.6.1.2 Reagents and materials
4.6.1.2.1 Hydrochloric acid (GB/T622) solution: 1+14.6.1.2.2 Lead standard solution: 1mL solution contains 0.1mgPb. 4.6.1.3 Instruments and equipment
Atomic absorption spectrophotometer: with lead hollow cathode lamp; wavelength: 283.3nm;
Flame: acetylene-air.
4.6.1.4 Analysis steps
4.6.1.4.1 Preparation of test solution
HG/T 2572-- 94
Weigh about 30g of sample (accurate to 0.01g). Place in a 250mL beaker, add a small amount of water to moisten, and add 150ml of hydrochloric acid solution to completely dissolve it. Transfer to a 250ml volumetric flask, dilute to the mark with water, and shake well. This is test solution A, and is used for the atomic absorption determination of lead, manganese, and copper content.
4.6.1.4.2 Determination
Use a pipette to take four portions of 10ml test solution A (4.6.1.4.1). Place each portion in a 100ml volumetric flask. The following operations are carried out according to GBT9723 Section 6.2.2 starting from ".·1) portion without adding standard solution, ··". 4.6.1.5 Expression of analysis results
Content X of lead oxide (in terms of Pb) expressed as mass percentage. Calculate according to formula (6): =c×100×10×100
m×250
Wherein: c--the concentration of the element to be measured in the test solution, mg/mL, obtained from the curve; the mass of the sample weighed in 4.6.1.4.1, g. 4.6.1.6 Allowable difference
The arithmetic mean of the parallel determination results is taken as the determination result. The absolute difference of the parallel determination results shall not exceed 0.002%. 4.6.2 Colorimetric method
4.6.2.1 Method summary
(6)
Under the masking of potassium arsenide, the lead ions in the sample react with monovalent sulfur to form a colored sulfide precipitate. When the lead content is low, a stable dark suspension is formed, which can be used for the visual colorimetric determination of lead. 4.6.2.2 Reagents and materials
4.6.2.2.1 Hydrochloric acid (GB/T622) solution: 1+3; 4.6.2.2.2 Nitrogen water (GB/T631) solution: 1+4; 4.6.2.2.3 Potassium cyanide solution: 100g/L; 4.6.2.2.4 Sodium sulfide (HG/T3-905) solution: 5g/L; 4.6.2.2.5 Lead standard solution: 1mL solution contains 0.1mgPb. 4.6.2.3 Analysis steps
4.6.2.3.1 Preparation of test solution
Weigh about 25g of sample (accurate to 0.01g). Add 120mL of hydrochloric acid solution to a 250ml beaker, heat to dissolve, and cool. Transfer to a 250ml volumetric flask, dilute to the mark, and shake to check. 4.6.2.3.2 Determination
Use a pipette to transfer 3 mL of the test solution and place it in a 50 mL colorimetric tube. Use ammonia solution to adjust until turbidity is just produced, and then add hydrochloric acid solution until the turbidity disappears. Add water to about 20 mL, add 28 mL of potassium cyanide solution and 1 mL of sodium sulfide solution, dilute with water to the scale, and shake well. Place in a hood for 10 minutes. The color should not be darker than the standard colorimetric solution. Preparation of standard colorimetric solution: Use a pipette to transfer 1 mL of the test solution and 0.2 mL (first-class product) and 1.0 mL (qualified product) of lead standard solution, - into a 50 mL colorimetric tube, and perform the same treatment as the test solution. 4.7 Determination of manganese oxide content
4.7.1 Atomic absorption method (arbitration method)
4.7.1.1 Method summary
See Article 3 of GB/T9723.
4.7.1.2 Reagents and materials
Manganese standard solution: 1ml. The solution contains 0.1mgMn. 197
4.7.1.3 Instruments and equipment
HG/T 2572-94
Atomic absorption spectrophotometer: with manganese hollow cathode lamp; wavelength: 279.5nm;
Flame: acetylene-air.
4.7.1.4 Analysis steps
Use a pipette to take 25mL of test solution A (4.6.1.4.1) in four portions. Place each in a 100mL volumetric flask. The following operations are carried out according to GB/T9723 Section 6.2.2 starting from "· (1) portion without adding standard solution, ···". 4.7.1.5 Expression of analysis results
The content of manganese oxide (in terms of Mn) expressed as mass percentage X is calculated according to formula (7): X,-×100X10-×100
Wherein: c——the concentration of the element to be measured in the test solution found from the curve, mg/mL; m——the mass of the sample weighed in 4.6.1.4.1, g. 4.7.1.6 Allowable difference
The arithmetic mean of the parallel determination results is taken as the determination result. The absolute difference of the parallel determination results shall not exceed 0.0002%. 4.7.2 Colorimetric method
4.7.2.1 Summary of the method
In an acidic medium, potassium periodate is used to oxidize Mn (V) in the sample to Mn (). The resulting pink color can be used for the visual colorimetric determination of manganese.
4.7.2.2 Reagents and materials
4.7.2.2.1 Potassium periodate (HG/T3-1158); 4.7.2.2.2 Sulfuric acid (GB/T625);
4.7.2.2.3 Phosphoric acid (GB/T 1282);
4.7.2.2.4 Nitric acid (GB/T626) solution: 1+3; 4.7.2.2.5 Manganese standard solution: 1mL solution contains 0.1mgMn. 4.7.2.3 Analysis steps
Weigh about 5g of sample (accurate to 0.01g). Place in a 100mL beaker, add 25mL nitric acid solution, and after the sample is completely dissolved, add 5mL sulfuric acid and 5mL phosphoric acid, then heat and boil for 5min, add 0.5g potassium periodate after cooling, and boil for 5-10min. After rapid cooling, transfer it to a 50mL colorimetric tube and dilute it to the scale with water. The pink color should not be darker than the standard colorimetric solution. Preparation of standard colorimetric solution: Use a pipette to transfer 0.5mL (equal product) and 1.5mL (qualified product) of manganese standard solution, and treat it in the same way as the sample solution.
4.8 Determination of copper oxide content
4.8.1 Atomic absorption method (arbitration method)
4.8.1.1 Summary of the method
See Article 3 of GB/T9723.
4.8.1.2 Reagents and materials
Copper standard solution, 1mL solution contains 0.1mgCu. 4.8.1.3 Instruments and equipment
Atomic absorption spectrophotometer: with copper hollow cathode lamp; wavelength: 324.7nm;
Flame: acetylene-air.
4.8.1.4 Analysis steps
HG/T 2572-94
Use a pipette to transfer 25mL of test solution A (4.6.1.4.1) in four portions. Place each portion in a 100mL volumetric flask. The following operations are carried out according to GB/T9723 Section 6.2.2 starting from "1) portion without adding standard solution." 4.8.1.5 Expression of analysis results
Content X of copper oxide (in terms of Cu) expressed as mass percentage: Calculate according to formula (8): X. = -×100×10×100
m×250
Wherein: c----Concentration of the element to be measured in the test solution found from the curve, mg/mL; m
-mass of the sample weighed in 4.6.1.4.1, g. 4.8.1.6 Allowable difference
The arithmetic mean of the parallel determination results is taken as the determination result. The absolute difference of the parallel determination results shall not exceed 0.0002%. 4.8.2 Colorimetric method
4.8.2.1 Summary of method
The copper ions in the sample are extracted with chloroform in an ammonium citrate medium with copper reagent as the color developer. The color generated in the organic phase can be used for visual colorimetric determination of copper.
4.8.2.2 Reagents and materials
4.8.2.2.1 Chloroform (GB/T682); 4.8.2.2.2 Nitric acid (GB/T626) solution: 1+1; 4.8.2.2.3 Ammonia (GB/T631) solution: 1+1; 4.8.2.2.4 Ammonium citrate solution: 200g/L; Preparation: Weigh 50g ammonium citrate and dissolve it in 250mL water. Take 100mL ammonium citrate solution, place it in a 250mL separatory funnel, add 2 drops of phenol indicator solution, adjust with ammonia solution until red appears, add 6 drops in excess, add 10mL sodium diethyldithiocarbamate solution and 25mL chloroform. Cover the bottle stopper and shake for 1min, let it stand for stratification, remove the organic phase, and add 10mL chloroform to repeat the extraction until the organic phase is colorless. Finally, separate and remove the organic phase, and transfer the ammonium citrate solution into a reagent bottle for later use. 4.8.2.2.5 Sodium diethyldithiocarbamate (copper reagent) (HG/T3-962) solution: 1g/L; 4.8.2.2.6 Phenol (GB/T10728) indicator solution: 10g/L; 4.8.2.2.7 Copper standard solution: 1mL solution contains 0.1mgCu. 4.8.2.3 Analysis steps
Weigh about 2g of sample (accurate to 0.01g), place it in a 100mL beaker, moisten it with a small amount of water, add 10mL nitric acid solution to dissolve it, heat and evaporate it until the solution is about 5mL, cool it, and transfer it all into a 250mL separatory funnel. Add water to about 30mL, add 40mlL ammonium citrate solution, 2 drops of phenolic acid indicator solution, adjust with ammonia solution until red appears, add 6 drops in excess, add 10mL copper reagent solution and 5mL chloroform, cover the bottle stopper and shake for 1min, let stand to separate, transfer the organic phase into a 25mL colorimetric tube, and extract the water layer repeatedly with 5mL chloroform each time until the organic phase is colorless. Combine the organic phases in the colorimetric tube, dilute to the scale with chloroform, and shake well. The yellow color should not be darker than the standard colorimetric solution.
Preparation of standard colorimetric solution: Use a pipette to transfer 0.2mL (first-class product) and 0.6mL (qualified product) of copper standard solution, and treat it in the same way as the sample.
4.9 Determination of fineness
4.9.1 Instruments and equipment
4.9.1.1 Test sieve (GB6003): R401/3 series, Φ75mmX50mm/45μm; 4.9.1.2 Soft brush;
4.9.1.3 Electric oven: the temperature can be controlled at 105~110℃. 199
4.9.2 Analysis steps
HG/T 2572—94
Weigh about 10g of sample (accurate to 0.01g), place it in a test sieve that has been weighed constant in advance, moisten the sample with water, immerse the lower part of the test sieve in dry water, and gently brush it with a soft brush. Replace the water as appropriate until the water is clear and there is no sample on the soft brush. Then rinse the test sieve with water and brush it twice with a brush. Place the test sieve in an electric oven and dry it at 105-110℃ to constant weight. 4.9.3 Expression of analysis results
Fineness expressed as mass percentage (expressed as sieve residue) X, calculated according to formula (9): X, -
Wu Zhong: mt'
-mass of sieve residue, g;
mass of test material, is.
4.10 Determination of bulk density
4.10.1 Summary of method
The sample falls freely through a funnel into a measuring cup of known mass and volume. After weighing and calculation, the bulk density of the sample is determined. 4.10.2 Instruments and equipment
Bulk density tester
As shown in the figure: The funnel is fixed on the bracket, and the measuring cup is located below the center line of the funnel, with a spacing of 30-50 mm. Figure Bulk Density Tester
1--Hop; 2·Baffle 3 Bracket; 4--Measuring Cup (9)
4.10.3 Analysis Steps
Let the sample fall freely through the funnel into a measuring cup of known mass and volume within 1 min. The cone of the sample should be higher than the wall of the measuring cup. Use a ruler to scrape off the higher part and accurately weigh the measuring cup containing the sample (accurate to 0.1 g). 4.10.4 Expression of Analysis Results
The bulk density X1 expressed as mass per unit volume is calculated according to formula (10): Xn-
Where: m,—mass of the sample and measuring cup, g; m
mass basis of a measuring cup, m;
volume of the measuring cup, mL.
4.10.5 Allowable difference
HG/T 2572 -- 94
The arithmetic mean of the parallel determination results shall be taken as the determination result. The absolute difference of the parallel determination results shall not exceed 0.02g/mL. 4.11 Determination of specific surface area
Determine in accordance with GB/T2922.
5 Inspection rules
5.1 All technical indicators listed in this standard are type inspection items, among which zinc oxide, moisture, water-soluble matter, ignition loss, hydrochloric acid insoluble matter, lead oxide, manganese oxide, copper oxide, fineness, and bulk density are factory inspection items and must be inspected batch by batch. Under normal production conditions, type inspection shall be carried out once every three months.
5.2 Industrial active zinc oxide shall be inspected by the quality supervision and inspection department of the manufacturer in accordance with the provisions of this standard. The manufacturer shall ensure that all industrial active zinc oxide shipped meets the requirements of this standard. Each batch of industrial active zinc oxide shipped out of the factory should be accompanied by a quality certificate. The content includes: manufacturer name, factory address, product name, grade, net weight, batch number or production date, proof that the product quality complies with this standard and the number of this standard. 5.3 The user has the right to accept the industrial active zinc oxide products received in accordance with the provisions of this standard. 5.4 Each batch of products shall not exceed 30t.
5.5 Determine the number of sampling units in accordance with the provisions of Article 6.6 of GB/T6678. When sampling, insert the sampler vertically from the center of the packaging bag to 3/4 of the depth of the material layer to take samples. After quickly mixing the collected samples, reduce them to about 500g according to the quartering method, and immediately divide them into two clean and dry wide-mouth bottles with ground stoppers and seal them. Paste labels on the bottles, indicating: manufacturer name, product name, grade, batch number, sampling date and name of the sampler. One bottle is used for inspection, and the other bottle is kept for three months for reference. 5.6 If one of the indicators in the test results does not meet the requirements of this standard, samples should be taken from twice the amount of packaging for verification. If only one indicator in the verification results does not meet the requirements of this standard, the entire batch of products cannot be accepted. 5.7 When the supply and demand parties have objections to the product quality, they shall be handled in accordance with the provisions of the "Product Quality Law of the People's Republic of China". 5.8 The rounded value comparison method specified in GB1250 shall be used to determine whether the test results meet the standards. 6 Marking, packaging, transportation, storage
6.1 The packaging bags of industrial active zinc oxide should have firm and clear markings, including: manufacturer name, factory address, product name, trademark, grade, net weight, batch number or production date, this standard number, and the "wet-afraid" mark specified in GB191. 6.2 Industrial active zinc oxide is packaged in three layers. The inner packaging uses two layers of polyethylene plastic film bags with specifications and dimensions of 600×450mm and a thickness of 0.1mm; the outer packaging uses polyethylene plastic woven bags with specifications and dimensions of 500×350mm. Its performance and inspection methods shall comply with the provisions of GB8946A. The net weight of each bag of this product is 25kg. 6.3 For the packaging of industrial active zinc oxide, the inner bags are tied manually with vinyl rope or rope of equivalent quality, or sealed with other equivalent methods; the outer bags are folded at a distance of not less than 30mm from the bag edge, and the doors are sewn with vinyl thread or other thread of equivalent quality at a distance of not less than 15mm from the bag edge, with a stitch length of 7 to 12mm, neat stitches, even stitch lengths, and no leaking or skipping stitches. 6.4 Industrial active zinc oxide should be covered during transportation to prevent rain and moisture. It is strictly forbidden to mix with alkali and acid items. 6.5 Industrial active zinc oxide should be stored in a cool, dry place to prevent rain and moisture. It is strictly forbidden to store it together with alkali and acid substances. 201
HG/T2572—94
Appendix A
Treatment of potassium cyanide waste liquid
(Supplement)
In order to prevent the pollution of cyanide-containing waste liquid, the waste liquid after the lead oxide content is determined should be treated. A1 Principle
In alkaline medium, use excess sodium hypochlorite to oxidize and decompose CN-: KCN+NaCIO—→NaCNO+KCl
2NaCNO+3NaCIO+H20—→2CO, + +N, + +2NaOH+3NaCIA2 Operation steps
Collect the waste liquid after each batch of products in a 500mL large-mouth volumetric bottle, adjust the pH of the waste liquid to 12 with 400g/L sodium hydroxide solution, add 250mL10% sodium hypochlorite solution, mix thoroughly, and discharge after 24 hours. Additional instructions:
This standard was proposed by the Technical Supervision Department of the Ministry of Chemical Industry of the People's Republic of China. This standard is under the jurisdiction of Tianjin Chemical Research Institute of the Ministry of Chemical Industry. This standard was drafted by Tianjin Chemical Research Institute of the Ministry of Chemical Industry, Guangxi Liucheng Jinjiao Chemical Plant, Hebei Xinji Chemical Plant No. 2, Henan Zhengzhou Zinc Products Plant, Hunan Lengshuitan Zinc Products Plant, and Hubei Huangshi Chemical Plant. The main drafters of this standard are Lu Siwei, Li Guangming, Yuan Shaoqiang, Wei Lixin, Ping Songlin, Ni Jingqing and Xu Gensheng.
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