Some standard content:
HG/T 2768—1996
This industry standard is formulated based on the standards of major domestic enterprises and is divided into two levels according to actual production conditions and user requirements. The differences from the existing enterprise standards are as follows:
1 The first-class indicators of main content and magnesium sulfate content in this industry standard are better than the current enterprise standard level. 2 Some enterprise standards stipulate two indicators, magnesium fluoride and silicon dioxide content. After analysis, these two indicators are already included in the water-insoluble matter, and users do not require them. Therefore, this industry standard does not stipulate these two indicators. The test method adopts the classic method that has been verified by many years of use. Appendix A of this standard is the appendix of the standard.
This standard is 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. Drafting units of this standard: Tianjin Chemical Research Institute of the Ministry of Chemical Industry, Jiangsu Sheyang County Chemical Building Materials Factory, and Qianjin Chemical Factory in Chongqing, Sichuan Province.
The main drafters of this standard are: Wang Qi, Chen Diansheng, Qiu Jian, Liu Chuangui, Xian Sishu, Cao Shuguang. 611
Chemical Industry Standard of the People's Republic of China
Industrial Magnesium Fluorosilicate
HG/T 2768—1996
This standard specifies the requirements, sampling, test methods, marking, packaging, transportation and storage of industrial magnesium fluosilicate. This standard applies to industrial magnesium fluosilicate prepared by the reaction of fluosilicic acid and magnesium oxide. This product is mainly used as a hardener and waterproofing agent to improve the hardness and strength of concrete. It is also used for fluorine weathering treatment of silica building surfaces, ceramic manufacturing, fabric insect prevention, etc. Molecular formula: MgSiF. ·6H,0
Relative molecular mass: 274.47 (according to the 1991 international relative atomic mass) Referenced Standards
The provisions contained in the following standards constitute the provisions of this standard through reference in this standard. When this standard is published, the versions shown are valid. All standards will be revised. Parties using this standard should explore the possibility of using the latest versions of the following standards. GB191-1990 Pictorial markings for packaging, storage and transportation
GB/T 601-1988
Preparation of standard solutions for titration analysis (volume analysis) of chemical reagents GB/T603-1988 Preparation of preparations and products used in test methods for chemical reagents (neqISO6353-1:1982) GB/T 1250-1989
Methods for expressing and determining limit values GB/T 6678-1986
GB/T 6682-1992
GB/T 8946-1988
3 Requirements
3.1 Appearance, white crystals.
General rules for sampling of chemical products
Specifications and test methods for water used in analytical laboratories (eqvISO3696:1987)Plastic woven bags
3.2Industrial magnesium fluorosilicate shall meet the requirements of Table 1. Table 1 Requirements
First-class products
Content of magnesium fluorosilicate (MgSiF6H,0)
Content of magnesium sulfate (MgSO4·7H.0)
Content of fluorosilicic acid (HzSiF.)
Content of insoluble matter
4Sampling
Each batch of products shall not exceed 36t.
Qualified products
4.2Determine the number of sampling units in accordance with the provisions of 6.6 of GB/T6678. When sampling, insert the sampler obliquely from the top of the packaging bag to 3/4 of the depth of the material layer. After mixing the collected samples, divide them into four parts to no less than 500 parts, and pack them in two clean and dry wide-mouth bottles with stoppers and seal them. Label the bottles with the manufacturer's name, product name, grade, batch number, sampling date and the name of the sampler. One bottle is used as a laboratory sample, and the other is kept for three months for reference. 4.3 If one of the test results does not meet the requirements of this standard, re-sampling should be carried out from twice the amount of packaging. If even one of the test results does not meet the requirements of this standard, the entire batch of products will be unqualified. 5 Test method
5.1 Use the rounded value comparison method specified in 5.2 of GB/T1250 to determine whether the test results meet the standard. 5.2 The reagents and water used in this standard, unless otherwise specified, refer to analytical pure reagents and grade 3 water specified in GB/T6682. The standard titration solutions, preparations and products used in the test, unless otherwise specified, are prepared in accordance with the provisions of GB/T601 and GB/T603. 5.3 Determination of magnesium fluorosilicate content
5.3.1 Method summary
Dissolve the sample in water, and mask the interfering ions with hydroxylamine hydrochloride, tartaric acid and potassium cyanide. In an ammonia solution, titrate with EDTA standard titration solution using chrome black T as an indicator.
5.3.2 Reagents and materials
Boric acid solution: 50 g/L;
5. 3.2. 1
Hydroxyamine hydrochloride solution: 100 g/L;
5. 3.2. 2
5. 3. 2. 3
Tartaric acid solution: 100 g/L;
5. 3. 2. 4
Potassium cyanide solution: 100 g/L;
Ammonia-ammonium chloride buffer solution A: pH 10;
Ethylenediaminetetraacetic acid disodium (EDTA) standard titration solution: c(CioHl.ONzNa2) about 0.02 mol/L;5. 3. 2. 6
Eriochrome black T indicator.
5. 3. 2.7
5.3.3 Analysis steps
Weigh about 1.5g of sample (accurate to 0.0002g), add water to dissolve, add 20mL of boric acid solution, transfer to a 250mL volumetric flask, dilute with water to the mark, and shake well. Use a pipette to transfer 25mL of the test solution, place it in a 250ml conical flask, add water to about 80ml., add 5ml of hydroxylamine hydrochloride solution, 5mL of tartaric acid solution, 4ml of potassium cyanide solution, and titrate with EDTA standard titration solution to the near end point (0.5ml~1mL less than the actual amount), add 20mL of ammonia-ammonium chloride buffer solution and a small amount of chrome black T indicator. Continue to titrate with EDTA standard titration solution until the solution changes from purple-red to pure blue as the end point. Perform a blank test at the same time. Collect the test solution and treat it according to the method in Appendix A. 5.3.4 Expression of analysis results
The content (X) of magnesium fluorosilicate (MgSiF.·6H,O) expressed as mass percentage is calculated according to formula (1): x (V-Vo)cX0.274 5×100X ×1.114m×250
_(V-Vo)cX274. 5 - X: × 1. 114m
Wherein: V—--the volume of EDTA standard titration solution consumed by the titration test solution, mL; V,--the volume of EDTA standard titration solution consumed by the titration blank test solution, mL; C—.The actual concentration of EDTA standard titration solution, mol/L; (1)
0.2745---the mass of magnesium fluorosilicate equivalent to 1.00ml.EDTA standard titration solution Lc (Ct.H14O:N2Na2）=1.000mol/L) expressed in grams;
X.…—··the mass percentage of magnesium sulfate measured according to 5.4;--the mass of the sample·g;
1.114--the coefficient for converting magnesium sulfate into magnesium fluorosilicate. 613
5.3.5 Allowable difference
HG/T 2768—1996
Take the arithmetic mean of the parallel determination results as the determination result, and the absolute difference of the parallel determination results shall not exceed 0.2%. 5.4 Determination of magnesium sulfate content
5.4.1 Summary of method
Dissolve the sample in ethanol solution, add lead nitrate to generate lead sulfate precipitation, in the presence of acetic acid-sodium acetate buffer solution, use xylenol orange as indicator solution, and titrate the lead sulfate with EDTA standard titration solution to calculate the magnesium sulfate content. 5.4.2 Reagents and materials
5.4.2.1 95% ethanol solution: 1+3;
5.4.2.2 Hydrochloric acid solution: 1+6;
5.4.2.3 Ammonia solution: 1+5;
5.4.2.4 Lead nitrate solution: 50g/L.;
5.4.2.5 Acetic acid-sodium acetate buffer solution: pH5.5; Dissolve 150g sodium acetate in water, add 50mL glacial acetic acid, dilute with water to 100ml, and shake. 5.4.2.6 Disodium ethylenediaminetetraacetate (EDTA) standard titration solution: c(CiH14ON2Na2) about 0.02mol/L; 5.4.2.7 Xylenol orange indicator solution: 2g/L. 5.4.3 Instruments and equipment
Microburette: the graduation value is 0.02mL or 0.05mL. 5.4.4 Analysis steps
Weigh about 3g of sample (accurate to 0.0002g), place it in a 150ml beaker, add 20mL of ethanol solution to dissolve, filter with fast filter paper, and wash the insoluble matter 5~6 times with 8mL~~9mL of ethanol solution each time; collect the filtrate and washing liquid in a 150mL beaker. Adjust the pH value to about 3 with hydrochloric acid or ammonia solution (check with precision pH test paper), add 5mL of lead nitrate solution, and stir rapidly for 5min; let it stand for 1.5h. Filter with slow filter paper, wash the precipitate 8~9 times with 8mL~9mL of ethanol solution each time. Put the filter paper and the precipitate back into the original beaker, add 15mL of buffer solution, boil slightly for 1~2min, and cool to room temperature. Add 60mL of water and 3 drops of xylenol orange indicator solution, use a microburette, and titrate with EDTA standard titration solution until the solution changes from purple-red to bright yellow. 5.4.5 Expression of analytical results
The content of magnesium sulfate (MgSO47H2O) expressed as mass percentage (X2) is calculated according to formula (2): X = c×0.246 5×100
Where: V--the volume of EDTA standard titration solution consumed by the titration test solution, mL; the actual concentration of EDTA standard titration solution, mol/L; (2)
0.2465--the mass of magnesium sulfate expressed in grams equivalent to 1.00mL EDTA standard titration solution Cc(C1HO:NzNaz)=1.000mol/L;
the mass of the sample, g.
5.4.6 Allowable difference
The arithmetic mean of the parallel determination results shall be taken as the determination result. The absolute time difference of the parallel determination results shall not exceed 0.02%. 5.5 Determination of fluorosilicic acid content
5.5.1 Summary of method
Dissolve fluorosilicic acid with ethanol, use phenolic acid as indicator solution, and titrate with sodium hydroxide standard titration solution. 5.5.2 Reagents and materials
5.5.2.1 95% ethanol neutral solution;
In about 200mL of ethanol, add 2 drops of phenolphthalein indicator solution and titrate with sodium hydroxide standard titration solution until it turns pink. 614
HG/T 2768---1996
5.5.2.2 Sodium hydroxide standard titration solution: c(NaOH) about 0.1mol/L; 5.5.2.3 Phenolphthalein indicator solution: 10g/L.
5.5.3 Analysis steps
Weigh about 5g of sample (accurate to 0.0002g), place in a 250mL iodine volumetric flask, add 50mL ethanol, cover with a stopper, and shake vigorously for 5 minutes. Filter and wash three times with ethanol, collect the filtrate and washing liquid in a 250ml conical flask, add 2 drops of phenolphthalein indicator solution, and titrate with sodium hydroxide standard titration solution until the solution turns pink and remains pink for 15 seconds. 5.5.4 Expression of analysis results
The content of fluorosilicic acid (H,SiF.) expressed as mass percentage (X,) is calculated according to formula (3): X: =Vc×0.07204×100
Vc×7.204
Wherein: V—the volume of sodium hydroxide standard titration solution consumed by the titration test solution, mL—the actual concentration of the sodium hydroxide standard titration solution, mol/L; (3)
0.07204—the mass of fluorosilicic acid in grams equivalent to 1.00 mL sodium hydroxide standard titration solution [c(NaOH)=1.000 mol/L);
The mass of the sample, g.
5.5.5 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%. 5.6 Determination of moisture
5.6.1 Instruments and equipment
5.6.1.1 Weighing bottle: d50mmX30mm;
5.6.1.2 Sulfuric acid dryer.
5.6.2 Analysis steps
Weigh about 2g of sample (accurate to 0.0002g) and place it in a weighing bottle that has been dried to constant weight in a sulfuric acid dryer. Place it in a sulfuric acid dryer, leave it for 48 hours, take it out and weigh it; place it in a sulfuric acid dryer again, leave it for 4 hours, take it out and weigh it until it reaches a constant weight. 5.6.3 Expression of analysis results
The water content (X,) expressed as a mass percentage is calculated according to formula (4): m2×100
Wherein: m1—…-the mass of the sample and the weighing bottle before drying, g; - the mass of the sample and the weighing bottle after drying, g; m2-
-the mass of the sample, g.
5.6.4 Allowable difference
The arithmetic mean of the parallel determination results is taken as the determination result, and the absolute difference of the parallel determination results shall not exceed 0.05%. 5.7 Determination of water-insoluble matter content
5.7.1 Instruments and equipment
Glass sand crucible: filter plate pore size 5μm~15μm. 5.7.2 Analysis steps
-(4)
Weigh about 10g of sample (accurate to 0.0002g), place in a 250ml beaker, add 50ml of water to dissolve. Filter through a glass crucible that has been dried to constant weight at 105℃~110℃, wash with water 5~6 times, and dry at 105℃~110℃ to constant weight. 5.7.3 Expression of analysis results bZxz.net
The water-insoluble matter (X.) expressed as mass percentage is calculated according to formula (5): 615
HG/T 2768-1996
Where: m.--mass of glass crucible and water-insoluble matter, g; m2
mass of glass crucible, g;
mass of sample, g.
5.7.4 Allowable difference
The arithmetic mean of the parallel determination results shall be taken as the determination result, and the absolute difference of the parallel determination results shall not exceed 0.02%. 6 Marking, packaging, transportation and storage
·(5)
6.1 The packaging of industrial magnesium fluorosilicate shall be firmly and clearly marked, including the manufacturer's name, address, product name, trademark, grade, net weight, batch number or production date, and the number of this standard and the "heat-averse" mark and "humidity-averse" mark specified in GB191. 6.2 Each batch of industrial magnesium fluorosilicate shipped shall be accompanied by a quality certificate. The content includes the manufacturer's name, address, product name, trademark, grade, net weight, batch number or production date, proof that the product quality complies with this standard and the number of this standard. 6.3 Industrial magnesium fluorosilicate shall be double-packed. The inner packaging shall be a polyethylene plastic film bag with a thickness of not less than 0.05mm; the outer packaging shall be a plastic woven bag. Its performance and inspection methods shall comply with the provisions of Type A in GB/T8946. Net weight of each bag is 25kg. 6.4 For industrial magnesium fluorosilicate packaging, the inner bag is tied manually with vinyl rope or other ropes of equivalent quality, or sealed with other equivalent methods; the outer bag is folded at a distance of not less than 30mm from the bag edge, and the mouth is sewn with vinyl thread or other thread of equivalent quality at a distance of not less than 15mm from the bag edge. The stitch length is 7mm to 12mm, the stitches are neat and the stitch length is uniform. There is no leakage or skipping. 6.5 Industrial magnesium fluorosilicate should be covered during transportation to prevent rain and moisture. 6.6 Industrial magnesium fluorosilicate should be stored in a cool and dry place to prevent rain and moisture. 616
HG/T2768—1996
Appendix A
(Appendix of the standard)
Treatment method of cyanide waste liquid
In order to prevent the pollution of cyanide waste liquid, the cyanide waste liquid after each analysis should be treated before discharge. A1 Method Summary
Under alkaline conditions, hypochlorite is used as an oxidant to oxidize and decompose cyanide ions into non-toxic nitrogen and carbon dioxide. 2CN +5C1O-+H20=N2++2CO2++20OH-+5CIA2
Operation steps
Collect the waste liquid in a 500mL beaker, place it in a fume hood, add 25g of bleaching powder, stir it thoroughly, and discharge it after 12 hours. The reagents used in the above operations are all industrial grade. 6175h. Filter with slow filter paper, wash the precipitate 8-9 times with 8mL-9mL ethanol solution each time. Put the filter paper and the precipitate back into the original beaker, add 15mL buffer solution, boil slightly for 1-2min, and cool to room temperature. Add 60mL water and 3 drops of xylenol orange indicator solution, use a microburette, and titrate with EDTA standard titration solution until the solution changes from purple-red to bright yellow. 5.4.5 Expression of analysis results
The content of magnesium sulfate (MgSO47H2O) expressed as mass percentage (X2) is calculated according to formula (2): X = c×0.246 5×100
Wherein: V--the volume of EDTA standard titration solution consumed by the titration test solution, mL; the actual concentration of EDTA standard titration solution, mol/L; (2)
0.2465--the mass of magnesium sulfate expressed in grams equivalent to 1.00 mL EDTA standard titration solution Cc(C1HO:NzNaz)=1.000 mol/L;
the mass of the sample, g.
5.4.6 Allowable difference
The arithmetic mean of the parallel determination results is taken as the determination result, and the absolute difference of the parallel determination results shall not exceed 0.02%. 5.5 Determination of Fluorosilicic Acid Content
5.5.1 Summary of Method
Dissolve the fluosilicic acid with ethanol, use phenolic acid as the indicator solution, and titrate with sodium hydroxide standard titration solution. 5.5.2 Reagents and Materials
5.5.2.1 95% ethanol neutral solution;
Add 2 drops of phenolphthalein indicator solution to about 200 mL of ethanol, and titrate with sodium hydroxide standard titration solution until it turns pink. 614
HG/T 2768---1996
5.5.2.2 Sodium hydroxide standard titration solution: c(NaOH) about 0.1 mol/L; 5.5.2.3 Phenolphthalein indicator solution: 10 g/L.
5.5.3 Analysis steps
Weigh about 5g of sample (accurate to 0.0002g), place in a 250mL iodine volumetric flask, add 50mL ethanol, cover with a stopper, and shake vigorously for 5 minutes. Filter and wash three times with ethanol, collect the filtrate and washing liquid in a 250ml conical flask, add 2 drops of phenolphthalein indicator solution, and titrate with sodium hydroxide standard titration solution until the solution turns pink and remains pink for 15 seconds. 5.5.4 Expression of analysis results
The content of fluorosilicic acid (H,SiF.) expressed as mass percentage (X,) is calculated according to formula (3): X: =Vc×0.07204×100
Vc×7.204
Wherein: V—the volume of sodium hydroxide standard titration solution consumed by the titration test solution, mL—the actual concentration of the sodium hydroxide standard titration solution, mol/L; (3)
0.07204—the mass of fluorosilicic acid in grams equivalent to 1.00 mL sodium hydroxide standard titration solution [c(NaOH)=1.000 mol/L);
The mass of the sample, g.
5.5.5 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%. 5.6 Determination of moisture
5.6.1 Instruments and equipment
5.6.1.1 Weighing bottle: d50mmX30mm;
5.6.1.2 Sulfuric acid dryer.
5.6.2 Analysis steps
Weigh about 2g of sample (accurate to 0.0002g) and place it in a weighing bottle that has been dried to constant weight in a sulfuric acid dryer. Place it in a sulfuric acid dryer, leave it for 48 hours, take it out and weigh it; place it in a sulfuric acid dryer again, leave it for 4 hours, take it out and weigh it until it reaches a constant weight. 5.6.3 Expression of analysis results
The water content (X,) expressed as a mass percentage is calculated according to formula (4): m2×100
Wherein: m1—…-the mass of the sample and the weighing bottle before drying, g; - the mass of the sample and the weighing bottle after drying, g; m2-
-the mass of the sample, g.
5.6.4 Allowable difference
The arithmetic mean of the parallel determination results is taken as the determination result, and the absolute difference of the parallel determination results shall not exceed 0.05%. 5.7 Determination of water-insoluble matter content
5.7.1 Instruments and equipment
Glass sand crucible: filter plate pore size 5μm~15μm. 5.7.2 Analysis steps
-(4)
Weigh about 10g of sample (accurate to 0.0002g), place in a 250ml beaker, add 50ml of water to dissolve. Filter through a glass crucible that has been dried to constant weight at 105℃~110℃, wash with water 5~6 times, and dry at 105℃~110℃ to constant weight. 5.7.3 Expression of analysis results
The water-insoluble matter (X.) expressed as mass percentage is calculated according to formula (5): 615
HG/T 2768-1996
Where: m.--mass of glass crucible and water-insoluble matter, g; m2
mass of glass crucible, g;
mass of sample, g.
5.7.4 Allowable difference
The arithmetic mean of the parallel determination results shall be taken as the determination result, and the absolute difference of the parallel determination results shall not exceed 0.02%. 6 Marking, packaging, transportation and storage
·(5)
6.1 The packaging of industrial magnesium fluorosilicate shall be firmly and clearly marked, including the manufacturer's name, address, product name, trademark, grade, net weight, batch number or production date, and the number of this standard and the "heat-averse" mark and "humidity-averse" mark specified in GB191. 6.2 Each batch of industrial magnesium fluorosilicate shipped shall be accompanied by a quality certificate. The content includes the manufacturer's name, address, product name, trademark, grade, net weight, batch number or production date, proof that the product quality complies with this standard and the number of this standard. 6.3 Industrial magnesium fluorosilicate shall be double-packed. The inner packaging shall be a polyethylene plastic film bag with a thickness of not less than 0.05mm; the outer packaging shall be a plastic woven bag. Its performance and inspection methods shall comply with the provisions of Type A in GB/T8946. Net weight of each bag is 25kg. 6.4 For industrial magnesium fluorosilicate packaging, the inner bag is tied manually with vinyl rope or other ropes of equivalent quality, or sealed with other equivalent methods; the outer bag is folded at a distance of not less than 30mm from the bag edge, and the mouth is sewn with vinyl thread or other thread of equivalent quality at a distance of not less than 15mm from the bag edge. The stitch length is 7mm to 12mm, the stitches are neat and the stitch length is uniform. There is no leakage or skipping. 6.5 Industrial magnesium fluorosilicate should be covered during transportation to prevent rain and moisture. 6.6 Industrial magnesium fluorosilicate should be stored in a cool and dry place to prevent rain and moisture. 616
HG/T2768—1996
Appendix A
(Appendix of the standard)
Treatment method of cyanide waste liquid
In order to prevent the pollution of cyanide waste liquid, the cyanide waste liquid after each analysis should be treated before discharge. A1 Method Summary
Under alkaline conditions, hypochlorite is used as an oxidant to oxidize and decompose cyanide ions into non-toxic nitrogen and carbon dioxide. 2CN +5C1O-+H20=N2++2CO2++20OH-+5CIA2
Operation steps
Collect the waste liquid in a 500mL beaker, place it in a fume hood, add 25g of bleaching powder, stir it thoroughly, and discharge it after 12 hours. The reagents used in the above operations are all industrial grade. 6175h. Filter with slow filter paper, wash the precipitate 8-9 times with 8mL-9mL ethanol solution each time. Put the filter paper and the precipitate back into the original beaker, add 15mL buffer solution, boil slightly for 1-2min, and cool to room temperature. Add 60mL water and 3 drops of xylenol orange indicator solution, use a microburette, and titrate with EDTA standard titration solution until the solution changes from purple-red to bright yellow. 5.4.5 Expression of analysis results
The magnesium sulfate (MgSO47H2O) content (X2) expressed as mass percentage is calculated according to formula (2): X = c×0.246 5×100
Wherein: V--the volume of EDTA standard titration solution consumed by the titration test solution, mL; the actual concentration of EDTA standard titration solution, mol/L; (2)
0.2465--the mass of magnesium sulfate expressed in grams equivalent to 1.00 mL EDTA standard titration solution Cc(C1HO:NzNaz)=1.000 mol/L;
the mass of the sample, g.
5.4.6 Allowable difference
The arithmetic mean of the parallel determination results is taken as the determination result, and the absolute difference of the parallel determination results shall not exceed 0.02%. 5.5 Determination of Fluorosilicic Acid Content
5.5.1 Summary of Method
Dissolve the fluosilicic acid with ethanol, use phenolic acid as the indicator solution, and titrate with sodium hydroxide standard titration solution. 5.5.2 Reagents and Materials
5.5.2.1 95% ethanol neutral solution;
Add 2 drops of phenolphthalein indicator solution to about 200 mL of ethanol, and titrate with sodium hydroxide standard titration solution until it turns pink. 614
HG/T 2768---1996
5.5.2.2 Sodium hydroxide standard titration solution: c(NaOH) about 0.1 mol/L; 5.5.2.3 Phenolphthalein indicator solution: 10 g/L.
5.5.3 Analysis steps
Weigh about 5g of sample (accurate to 0.0002g), place in a 250mL iodine volumetric flask, add 50mL ethanol, cover with a stopper, and shake vigorously for 5 minutes. Filter and wash three times with ethanol, collect the filtrate and washing liquid in a 250ml conical flask, add 2 drops of phenolphthalein indicator solution, and titrate with sodium hydroxide standard titration solution until the solution turns pink and remains pink for 15 seconds. 5.5.4 Expression of analysis results
The content of fluorosilicic acid (H,SiF.) expressed as mass percentage (X,) is calculated according to formula (3): X: =Vc×0. 072 04 × 100
Vc×7. 204
Wherein: V—the volume of sodium hydroxide standard titration solution consumed by the titration test solution, mL—the actual concentration of the sodium hydroxide standard titration solution, mol/L; (3)
0.07204—the mass of fluorosilicic acid in grams equivalent to 1.00 mL sodium hydroxide standard titration solution [c (NaOH) = 1.000 mol/L);
The mass of the sample, g.
5.5.5 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%. 5.6 Determination of moisture
5.6.1 Instruments and equipment
5.6.1.1 Weighing bottle: d50mmX30mm;
5.6.1.2 Sulfuric acid dryer.
5.6.2 Analysis steps
Weigh about 2g of sample (accurate to 0.0002g) and place it in a weighing bottle that has been dried to constant weight in a sulfuric acid dryer. Place it in a sulfuric acid dryer, leave it for 48 hours, take it out and weigh it; place it in a sulfuric acid dryer again, leave it for 4 hours, take it out and weigh it until it reaches a constant weight. 5.6.3 Expression of analysis results
The water content (X,) expressed as a mass percentage is calculated according to formula (4): m2×100
Wherein: m1—…-the mass of the sample and weighing bottle before drying, g; - the mass of the sample and weighing bottle after drying, g; m2-
-the mass of the sample, g.
5.6.4 Allowable difference
The arithmetic mean of the parallel determination results is taken as the determination result, and the absolute difference of the parallel determination results shall not exceed 0.05%. 5.7 Determination of water-insoluble matter content
5.7.1 Instruments and equipment
Glass sand crucible: filter plate pore size 5μm~15μm. 5.7.2 Analysis steps
-(4)
Weigh about 10g of sample (accurate to 0.0002g), place in a 250ml beaker, add 50ml of water to dissolve. Filter through a glass crucible that has been dried to constant weight at 105℃~110℃, wash with water 5~6 times, and dry at 105℃~110℃ to constant weight. 5.7.3 Expression of analysis results
The water-insoluble matter (X.) expressed as mass percentage is calculated according to formula (5): 615
HG/T 2768-1996
Where: m.--mass of glass crucible and water-insoluble matter, g; m2
mass of glass crucible, g;
mass of sample, g.
5.7.4 Allowable difference
The arithmetic mean of the parallel determination results shall be taken as the determination result, and the absolute difference of the parallel determination results shall not exceed 0.02%. 6 Marking, packaging, transportation and storage
·(5)
6.1 The packaging of industrial magnesium fluorosilicate shall be firmly and clearly marked, including the manufacturer's name, address, product name, trademark, grade, net weight, batch number or production date, and the number of this standard and the "heat-averse" mark and "humidity-averse" mark specified in GB191. 6.2 Each batch of industrial magnesium fluorosilicate shipped shall be accompanied by a quality certificate. The content includes the manufacturer's name, address, product name, trademark, grade, net weight, batch number or production date, the certificate that the product quality complies with this standard and the number of this standard. 6.3 Industrial magnesium fluorosilicate shall be double-packed. The inner packaging shall be a polyethylene plastic film bag with a thickness of not less than 0.05mm; the outer packaging shall be a plastic woven bag. Its performance and inspection methods shall comply with the provisions of Type A in GB/T8946. Net weight of each bag is 25kg. 6.4 For industrial magnesium fluorosilicate packaging, the inner bag is tied manually with vinyl rope or other ropes of equivalent quality, or sealed with other equivalent methods; the outer bag is folded at a distance of not less than 30mm from the bag edge, and the mouth is sewn with vinyl thread or other thread of equivalent quality at a distance of not less than 15mm from the bag edge. The stitch length is 7mm to 12mm, the stitches are neat and the stitch length is uniform. There is no leakage or skipping. 6.5 Industrial magnesium fluorosilicate should be covered during transportation to prevent rain and moisture. 6.6 Industrial magnesium fluorosilicate should be stored in a cool and dry place to prevent rain and moisture. 616
HG/T2768—1996
Appendix A
(Appendix to the standard)
Treatment method of cyanide waste liquid
In order to prevent the pollution of cyanide waste liquid, the cyanide waste liquid after each analysis should be treated before discharge. A1 Method Summary
Under alkaline conditions, hypochlorite is used as an oxidant to oxidize and decompose cyanide ions into non-toxic nitrogen and carbon dioxide. 2CN +5C1O-+H20=N2++2CO2++20OH-+5CIA2
Operation steps
Collect the waste liquid in a 500mL beaker, place it in a fume hood, add 25g of bleaching powder, stir it thoroughly, and discharge it after 12 hours. The reagents used in the above operations are all industrial grade. 6173 Phenolphthalein indicator solution: 10g/L.
5.5.3 Analysis steps
Weigh about 5g of sample (accurate to 0.0002g), place in a 250mL iodine volumetric flask, add 50mL ethanol, cover with a stopper, and shake vigorously for 5min. Filter and wash three times with ethanol, collect the filtrate and washing liquid in a 250ml conical flask, add 2 drops of phenolphthalein indicator solution, and titrate with sodium hydroxide standard titration solution until the solution turns pink and remains pink for 15s. 5.5.4 Expression of analysis results
The content of fluorosilicic acid (H,SiF.) expressed as mass percentage (X,) is calculated according to formula (3): X: =Vc×0. 072 04 × 100
Vc×7. 204
Wherein: V—the volume of sodium hydroxide standard titration solution consumed by the titration test solution, mL—the actual concentration of the sodium hydroxide standard titration solution, mol/L; (3)
0.07204—the mass of fluorosilicic acid in grams equivalent to 1.00 mL sodium hydroxide standard titration solution [c (NaOH) = 1.000 mol/L);
The mass of the sample, g.
5.5.5 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%. 5.6 Determination of moisture
5.6.1 Instruments and equipment
5.6.1.1 Weighing bottle: d50mmX30mm;
5.6.1.2 Sulfuric acid dryer.
5.6.2 Analysis steps
Weigh about 2g of sample (accurate to 0.0002g) and place it in a weighing bottle that has been dried to constant weight in a sulfuric acid dryer. Place it in a sulfuric acid dryer, leave it for 48 hours, take it out and weigh it; place it in a sulfuric acid dryer again, leave it for 4 hours, take it out and weigh it until it reaches a constant weight. 5.6.3 Expression of analysis results
The water content (X,) expressed as a mass percentage is calculated according to formula (4): m2×100
Wherein: m1—…-the mass of the sample and weighing bottle before drying, g; - the mass of the sample and weighing bottle after drying, g; m2-
-the mass of the sample, g.
5.6.4 Allowable difference
The arithmetic mean of the parallel determination results is taken as the determination result, and the absolute difference of the parallel determination results shall not exceed 0.05%. 5.7 Determination of water-insoluble matter content
5.7.1 Instruments and equipment
Glass sand crucible: filter plate pore size 5μm~15μm. 5.7.2 Analysis steps
-(4)
Weigh about 10g of sample (accurate to 0.0002g), place in a 250ml beaker, add 50ml of water to dissolve. Filter through a glass crucible that has been dried to constant weight at 105℃~110℃, wash with water 5~6 times, and dry at 105℃~110℃ to constant weight. 5.7.3 Expression of analysis results
The water-insoluble matter (X.) expressed as mass percentage is calculated according to formula (5): 615
HG/T 2768-1996
Where: m.--mass of glass crucible and water-insoluble matter, g; m2
mass of glass crucible, g;
mass of sample, g.
5.7.4 Allowable difference
The arithmetic mean of the parallel determination results shall be taken as the determination result, and the absolute difference of the parallel determination results shall not exceed 0.02%. 6 Marking, packaging, transportation and storage
·(5)
6.1 The packaging of industrial magnesium fluorosilicate shall be firmly and clearly marked, including the manufacturer's name, address, product name, trademark, grade, net weight, batch number or production date, and the number of this standard and the "heat-averse" mark and "humidity-averse" mark specified in GB191. 6.2 Each batch of industrial magnesium fluorosilicate shipped shall be accompanied by a quality certificate. The content includes the manufacturer's name, address, product name, trademark, grade, net weight, batch number or production date, the certificate that the product quality complies with this standard and the number of this standard. 6.3 Industrial magnesium fluorosilicate shall be double-packed. The inner packaging shall be a polyethylene plastic film bag with a thickness of not less than 0.05mm; the outer packaging shall be a plastic woven bag. Its performance and inspection methods shall comply with the provisions of Type A in GB/T8946. Net weight of each bag is 25kg. 6.4 For industrial magnesium fluorosilicate packaging, the inner bag is tied manually with vinyl rope or other ropes of equivalent quality, or sealed with other equivalent methods; the outer bag is folded at a distance of not less than 30mm from the bag edge, and the mouth is sewn with vinyl thread or other thread of equivalent quality at a distance of not less than 15mm from the bag edge. The stitch length is 7mm to 12mm, the stitches are neat and the stitch length is uniform. There is no leakage or skipping. 6.5 Industrial magnesium fluorosilicate should be covered during transportation to prevent rain and moisture. 6.6 Industrial magnesium fluorosilicate should be stored in a cool and dry place to prevent rain and moisture. 616
HG/T2768—1996
Appendix A
(Appendix to the standard)
Treatment method of cyanide waste liquid
In order to prevent the pollution of cyanide waste liquid, the cyanide waste liquid after each analysis should be treated before discharge. A1 Method Summary
Under alkaline conditions, hypochlorite is used as an oxidant to oxidize and decompose cyanide ions into non-toxic nitrogen and carbon dioxide. 2CN +5C1O-+H20=N2++2CO2++20OH-+5CIA2
Operation steps
Collect the waste liquid in a 500mL beaker, place it in a fume hood, add 25g of bleaching powder, stir it thoroughly, and discharge it after 12 hours. The reagents used in the above operations are all industrial grade. 6173 Phenolphthalein indicator solution: 10g/L.
5.5.3 Analysis steps
Weigh about 5g of sample (accurate to 0.0002g), place in a 250mL iodine volumetric flask, add 50mL ethanol, cover with a stopper, and shake vigorously for 5min. Filter and wash three times with ethanol, collect the filtrate and washing liquid in a 250ml conical flask, add 2 drops of phenolphthalein indicator solution, and titrate with sodium hydroxide standard titration solution until the solution turns pink and remains pink for 15s. 5.5.4 Expression of analysis results
The content of fluorosilicic acid (H,SiF.) expressed as mass percentage (X,) is calculated according to formula (3): X: =Vc×0.07204×100
Vc×7.204
Wherein: V—the volume of sodium hydroxide standard titration solution consumed by the titration test solution, mL—the actual concentration of the sodium hydroxide standard titration solution, mol/L; (3)
0.07204—the mass of fluorosilicic acid in grams equivalent to 1.00 mL sodium hydroxide standard titration solution [c(NaOH)=1.000 mol/L);
The mass of the sample, g.
5.5.5 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%. 5.6 Determination of moisture
5.6.1 Instruments and equipment
5.6.1.1 Weighing bottle: d50mmX30mm;
5.6.1.2 Sulfuric acid dryer.
5.6.2 Analysis steps
Weigh about 2g of sample (accurate to 0.0002g) and place it in a weighing bottle that has been dried to constant weight in a sulfuric acid dryer. Place it in a sulfuric acid dryer, leave it for 48 hours, take it out and weigh it; place it in a sulfuric acid dryer again, leave it for 4 hours, take it out and weigh it until it reaches a constant weight. 5.6.3 Expression of analysis results
The water content (X,) expressed as a mass percentage is calculated according to formula (4): m2×100
Wherein: m1—…-the mass of the sample and the weighing bottle before drying, g; - the mass of the sample and the weighing bottle after drying, g; m2-
-the mass of the sample, g.
5.6.4 Allowable difference
The arithmetic mean of the parallel determination results is taken as the determination result, and the absolute difference of the parallel determination results shall not exceed 0.05%. 5.7 Determination of water-insoluble matter content
5.7.1 Instruments and equipment
Glass sand crucible: filter plate pore size 5μm~15μm. 5.7.2 Analysis steps
-(4)
Weigh about 10g of sample (accurate to 0.0002g), place in a 250ml beaker, add 50ml of water to dissolve. Filter through a glass crucible that has been dried to constant weight at 105℃~110℃, wash with water 5~6 times, and dry at 105℃~110℃ to constant weight. 5.7.3 Expression of analysis results
The water-insoluble matter (X.) expressed as mass percentage is calculated according to formula (5): 615
HG/T 2768-1996
Where: m.--mass of glass crucible and water-insoluble matter, g; m2
mass of glass crucible, g;
mass of sample, g.
5.7.4 Allowable difference
The arithmetic mean of the parallel determination results shall be taken as the determination result, and the absolute difference of the parallel determination results shall not exceed 0.02%. 6 Marking, packaging, transportation and storage
·(5)
6.1 The packaging of industrial magnesium fluorosilicate shall be firmly and clearly marked, including the manufacturer's name, address, product name, trademark, grade, net weight, batch number or production date, and the number of this standard and the "heat-averse" mark and "humidity-averse" mark specified in GB191. 6.2 Each batch of industrial magnesium fluorosilicate shipped shall be accompanied by a quality certificate. The content includes the manufacturer's name, address, product name, trademark, grade, net weight, batch number or production date, proof that the product quality complies with this standard and the number of this standard. 6.3 Industrial magnesium fluorosilicate shall be double-packed. The inner packaging shall be a polyethylene plastic film bag with a thickness of not less than 0.05mm; the outer packaging shall be a plastic woven bag. Its performance and inspection methods shall comply with the provisions of Type A in GB/T8946. Net weight of each bag is 25kg. 6.4 For industrial magnesium fluorosilicate packaging, the inner bag is tied manually with vinyl rope or other ropes of equivalent quality, or sealed with other equivalent methods; the outer bag is folded at a distance of not less than 30mm from the bag edge, and the mouth is sewn with vinyl thread or other thread of equivalent quality at a distance of not less than 15mm from the bag edge. The stitch length is 7mm to 12mm, the stitches are neat and the stitch length is uniform. There is no leakage or skipping. 6.5 Industrial magnesium fluorosilicate should be covered during transportation to prevent rain and moisture. 6.6 Industrial magnesium fluorosilicate should be stored in a cool and dry place to prevent rain and moisture. 616
HG/T2768—1996
Appendix A
(Appendix of the standard)
Treatment method of cyanide waste liquid
In order to prevent the pollution of cyanide waste liquid, the cyanide waste liquid after each analysis should be treated before discharge. A1 Method Summary
Under alkaline conditions, hypochlorite is used as an oxidant to oxidize and decompose cyanide ions into non-toxic nitrogen and carbon dioxide. 2CN +5C1O-+H20=N2++2CO2++20OH-+5CIA2
Operation steps
Collect the waste liquid in a 500mL beaker, place it in a fume hood, add 25g of bleaching powder, stir it thoroughly, and discharge it after 12 hours. The reagents used in the above operations are all industrial grade. 6174 Allowable difference
The arithmetic mean of the parallel determination results shall be taken as the determination result, and the absolute difference of the parallel determination results shall not exceed 0.02%. 6 Marking, packaging, transportation, storage
·(5)
6.1 The packaging of industrial magnesium fluorosilicate shall be firmly and clearly marked, including the manufacturer's name, address, product name, trademark, grade, net weight, batch number or production date, and the number of this standard and the "heat-averse" mark and "humidity-averse" mark specified in GB191. 6.2 Each batch of industrial magnesium fluorosilicate shipped shall be accompanied by a quality certificate. The content includes the manufacturer's name, address, product name, trademark, grade, net weight, batch number or production date, proof that the product quality complies with this standard, and the number of this standard. 6.3 Industrial magnesium fluorosilicate shall be double-packed. The inner packaging shall be a polyethylene plastic film bag with a thickness of not less than 0.05mm; the outer packaging shall be a plastic woven bag. Its performance and inspection methods shall comply with the provisions of Type A in GB/T8946. Net weight of each bag is 25kg. 6.4 For industrial magnesium fluorosilicate packaging, the inner bag is tied with vinyl rope or other ropes of equivalent quality, or sealed with other equivalent methods; the outer bag is folded at a distance of not less than 30mm from the bag edge, and the outer bag is sewn with vinyl thread or other thread of equivalent quality at a distance of not less than 15mm from the bag edge. The stitch length is 7mm~12mm, the stitches are neat and the stitch length is uniform. There is no leakage and skipping. 6.5 Industrial magnesium fluorosilicate should be covered during transportation to prevent rain and moisture. 6.6 Industrial magnesium fluorosilicate should be stored in a cool and dry place to prevent rain and moisture. 616
HG/T2768—1996
Appendix A
(Appendix to the standard)
Treatment method of cyanide waste liquid
In order to prevent the pollution of cyanide waste liquid, the cyanide waste liquid after each analysis should be treated before discharge. A1 Method Summary
Under alkaline conditions, hypochlorite is used as an oxidant to oxidize cyanide ions into non-toxic nitrogen and carbon dioxide. 2CN +5C1O-+H20=N2++2CO2++20OH-+5CIA2
Operation Steps
Collect the waste liquid in a 500mL beaker, place it in a fume hood, add 25g of bleaching powder, stir it thoroughly, and discharge it after 12 hours. The reagents used in the above operation are all industrial grade. 6174 Allowable difference
The arithmetic mean of the parallel determination results shall be taken as the determination result, and the absolute difference of the parallel determination results shall not exceed 0.02%. 6 Marking, packaging, transportation, storage
·(5)
6.1 The packaging of industrial magnesium fluorosilicate shall be firmly and clearly marked, including the manufacturer's name, address, product name, trademark, grade, net weight, batch number or production date, and the number of this standard and the "heat-averse" mark and "humidity-averse" mark specified in GB191. 6.2 Each batch of industrial magnesium fluorosilicate shipped shall be accompanied by a quality certificate. The content includes the manufacturer's name, address, product name, trademark, grade, net weight, batch number or production date, proof that the product quality complies with this standard, and the number of this standard. 6.3 Industrial magnesium fluorosilicate shall be double-packed. The inner packaging shall be a polyethylene plastic film bag with a thickness of not less than 0.05mm; the outer packaging shall be a plastic woven bag. Its performance and inspection methods shall comply with the provisions of Type A in GB/T8946. Net weight of each bag is 25kg. 6.4 For industrial magnesium fluorosilicate packaging, the inner bag is tied with vinyl rope or other ropes of equivalent quality, or sealed with other equivalent methods; the outer bag is folded at a distance of not less than 30mm from the bag edge, and the outer bag is sewn with vinyl thread or other thread of equivalent quality at a distance of not less than 15mm from the bag edge. The stitch length is 7mm~12mm, the stitches are neat and the stitch length is uniform. There is no leakage and skipping. 6.5 Industrial magnesium fluorosilicate should be covered during transportation to prevent rain and moisture. 6.6 Industrial magnesium fluorosilicate should be stored in a cool and dry place to prevent rain and moisture. 616
HG/T2768—1996
Appendix A
(Appendix to the standard)
Treatment method of cyanide waste liquid
In order to prevent the pollution of cyanide waste liquid, the cyanide waste liquid after each analysis should be treated before discharge. A1 Method Summary
Under alkaline conditions, hypochlorite is used as an oxidant to oxidize cyanide ions into non-toxic nitrogen and carbon dioxide. 2CN +5C1O-+H20=N2++2CO2++20OH-+5CIA2
Operation Steps
Collect the waste liquid in a 500mL beaker, place it in a fume hood, add 25g of bleaching powder, stir it thoroughly, and discharge it after 12 hours. The reagents used in the above operation are all industrial grade. 617
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