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HG/T 2831-1997 Industrial manganese dihydrogen phosphate

Basic Information

Standard ID: HG/T 2831-1997

Standard Name: Industrial manganese dihydrogen phosphate

Chinese Name: 工业磷酸二氢锰

Standard category:Chemical industry standards (HG)

state:in force

Date of Release1997-02-04

Date of Implementation:1997-10-01

standard classification number

Standard ICS number:Chemical Technology>>Inorganic Chemistry>>71.060.50 Salt

Standard Classification Number:Chemicals>>Inorganic Chemical Raw Materials>>G12 Inorganic Salt

associated standards

Publication information

publishing house:Chemical Industry Press

Publication date:2004-04-18

other information

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HG/T 2831-1997 Industrial Manganese Dihydrogen Phosphate HG/T2831-1997 Standard download decompression password: www.bzxz.net

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HG/T 2831—1997
This standard is formulated according to domestic enterprise standards. Compared with domestic enterprise standards: 1. The requirements of this standard are divided into two levels: first-class products and qualified products. 2. The index items set by each enterprise standard are different. This standard sets 8 indicators according to user requirements: manganese (Mn) content, phosphoric acid and phosphate (in PO) content, iron (Fe) content, sulfate (in SO) content, total acidity (titer), hydrolysis insoluble matter content, and heating loss. 3. The test method is greatly improved compared with the enterprise standard. For the determination of phosphorus pentoxide, this industry standard adopts the internationally used quinoline molybdenum acetone weight method, and the determination of manganese content adopts the ammonium ferrous sulfate method. The determination methods of other items are all based on relevant Chinese standards. 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 the Tianjin Chemical Research Institute of the Ministry of Chemical Industry. The drafting units of this standard: Tianjin Chemical Research Institute of the Ministry of Chemical Industry, Hunan Chemical Reagent General Factory, Chongqing Chemical Reagent General Factory, and Chongqing South China Chemical Plant.
The main drafters of this standard are Liu Shuying, Yin Zhaowu, Lin Wenxin, Jiang Xingchang and Yu Chaohui. The Ministry of Chemical Industry is entrusted with the interpretation of this standard by the technical unit responsible for standardization of inorganic salt products. 727
1 Scope
Chemical Industry Standard of the People's Republic of China
Industrial manganese dihydrogen phosphate
Manganese dihydrogen phosphate for industrial useHG/T 2831—1997
This standard specifies the requirements, sampling, test methods, marking, packaging, transportation and storage of industrial manganese dihydrogen phosphate. This standard is applicable to industrial manganese dihydrogen phosphate produced by manganese carbonate method, manganese sulfate method and electrolytic manganese method. This product is mainly used as an anti-rust phosphating agent for steel products and as a lubricating layer and protective layer for various weapons in the national defense industry. Molecular formula: Mn(HzPO)2·xH,O
2 Cited 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, and parties using this standard should explore the possibility of using the latest versions of the following standards. GB 191—1990
Pictorial marking for packaging, storage and transportation
GR/T 601-1988
GB/T 602-1988
GB/T 603—1988
Chemical reagents-Preparation of standard solutions for titration analysis (volume analysis) Chemical reagents
Preparation of standard solutions for determination of impurities (neqISO6353-1:1982) Preparation of preparations and products used in test methods (neqISO6353-1:1982) Chemical reagents
GB/T 1250-1989
GB/T 3049—1986
GB/T 6678—1986
GB/T 6682—-1992
GB/T 8946-1988
GB/T 8947-1988
3 Requirements
Methods for expressing and determining limit values ​​General method for determination of iron content in chemical products O-phenanthroline spectrophotometric method Chemical product sampling total toilet
Analysis Laboratory water specifications and test methods (egvISO3696:1987) Plastic woven bags
Composite plastic woven bags
3.1 Appearance: white, off-white or slightly reddish crystals. 3.2 Industrial manganese dihydrogen phosphate should meet the requirements of Table 1. Table 1 Requirements
Phosphoric acid and phosphate (in terms of P, Os) content/%Manganese (Mn) content/%
Iron (Fe) content/%
Sulfate (in terms of S()) content/%
Total acidity (titer)
Approved by the Ministry of Chemical Industry of the People's Republic of China on February 4, 1997728
First-class productbzxz.net
46.0~-52.0
Qualified product
46.0~52.0
Implemented on October 1, 1997
Content of insoluble matter in hydrolysis/%
Heating loss/%
4 Sampling
4.1 Each batch of products shall not exceed 5t.
HG/T 2831—1997
Table 1 (end)
First-class products
Qualified products
4.2 Determine the number of sampling units according to the provisions of 6.6 of GB/T6678. Each plastic woven bag is a packaging unit. When sampling, insert the sampler obliquely to 3/4 of the depth of the material layer to take samples. From each selected packaging unit, take out no less than 50g of sample, mix the collected sample and reduce it to about 500g by quartering method, and immediately put it 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 as a laboratory sample, and the other bottle is kept for three months for reference.
4.3 If one of the test results does not meet the requirements of this standard, samples should be taken from twice the amount of packaging for re-verification. Even if only one of the test results does not meet the requirements of this standard, the entire batch of products shall be unqualified. 5 Test method
5.1 The rounded value comparison method specified in 5.2 of GB/T1250 shall be used to determine whether the test results meet the standards. 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, impurity standard solutions, preparations and products used in the test, unless otherwise specified, shall be prepared in accordance with the provisions of GB/T601, GB/T602 and GB/T603.
5.3 Determination of phosphoric acid and phosphate (in terms of P2Os) content 5.3.1 Summary of method
In an acidic medium, all phosphates in the test solution form precipitation with the added quinoline molybdate. After filtering, drying and weighing, the phosphoric acid and phosphate content are calculated.
5.3.2 Reagents and Materials
5.3.2.1 Hydrochloric acid solution: 1+1;
5.3.2.2 Nitric acid solution: 1+1;
5.3.2.3 Quinoline solution;
Preparation of Quinoline solution
Weigh 70g sodium molybdate and dissolve it in 100mL water; a.
Weigh 60g citric acid and dissolve it in 150mL water and 85mL nitric acid; b.
Pour solution a into solution b under stirring; add 35mL nitric acid and 5mL quinoline to 100mL water; d.
Pour solution d into solution c, let it stand for 12h, filter it with a glass sand crucible, add 280mL acetone, dilute it with water to e.
1000mL, mix well. And store it in a polyethylene bottle. 5.3.3 Instruments and equipment
5.3.3.1 Glass crucible: pore size 5μm~15μm; 5.3.3.2 Electric oven: temperature can be controlled at 180℃±5℃. 5.3.4 Analysis steps
5.3.4.1 Preparation of test solution
Weigh about 5g of sample (accurate to 0.0002g), place it in a 250ml beaker, add 60mL of hydrochloric acid solution, heat to dissolve, cool down and transfer to a 500ml volumetric flask, dilute to the mark with water, shake well (dry filter if necessary). This is test solution A, and keep this solution for the determination of iron content.
5.3.4.2 Preparation of test blank solution
Except for not adding the sample, the amount of reagents added is exactly the same as that of test solution A, and the same treatment is performed as for the sample. 5.3.4.3 Determination
Use a pipette to transfer 10 mL of test solution A (5.3.4.1) and test blank solution (5.3.4.2) into a 250 mL beaker, add 10 mL of nitric acid solution, add water to a total volume of about 100 mL, add 50 mL of quinoline molybdate solution, cover with a watch glass, and heat in a water bath until the contents of the beaker reach 75°C ± 5°C, and keep warm for 30 seconds (do not use open flames or stir during the addition of reagents and heating to avoid condensation). Cool, stir 3-4 times during the cooling process, filter the upper clear liquid through a glass sand crucible that has been dried to constant weight at 180℃±5℃, rinse the precipitate 6 times with a washing bottle by decanting method, using about 30ml of water each time. Finally, transfer the precipitate to glass sand for filtration, and then wash the precipitate 4 times with water. Put the glass sand and the precipitate in an electric oven and start timing from the time the temperature stabilizes, dry at 180℃±5℃ for 45 minutes, take out and cool slightly, then put it in a desiccator to cool to room temperature, and weigh it. 5.3.5. Expression of analytical results
The content of phosphoric acid and phosphate (in terms of P2O,) expressed as mass percentage (X) is calculated according to formula (1): X; =(m_ =m) X0 032 07 × 100x
=160.4 ×(ml -m2)
Wherein: m is the mass of quinoline phosphomolybdic acid precipitate generated in the test solution, g; the mass of quinoline phosphomolybdic acid precipitate generated in the test blank solution, g; m2
m is the mass of the sample, g;
the coefficient for converting quinoline phosphomolybdic acid into phosphorus pentoxide. 5.3.6 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 0.2%. 5.4 Determination of manganese (Mn) content
5.4.1 Summary of method
In phosphoric acid medium, use ammonium nitrate to quantitatively oxidize the divalent manganese in the sample into trivalent manganese at 220℃~240℃, and titrate with standard ammonium ferrous sulfate solution using N-phenylanthranilic acid as indicator. 5.4.2 Reagents and materials
5.4.2.1 Sulfuric acid;
5.4.2.2 Phosphoric acid;
5.4.2.3 Nitric acid;
5.4.2.4 Ammonium nitrate;
5.4.2.5 Sulfuric acid solution: 1+8;
5.4.2.6 Mixed solution of sulfur and phosphoric acid: H:PO4+H2SO4+H2O:1+1+4;5.4.2.7 N-phenylated o-phenylaminobenzoic acid indicator solution: 2g/L; Preparation: Weigh 0.2g N-phenylated o-phenylaminobenzoic acid and dissolve it in 100mL (2g/1) sodium carbonate solution. 5. 4. 2.8 Potassium dichromate standard solution: c(K:Cr:0,) is about 0.1 mol/L. Preparation: Weigh about 5g of the standard potassium dichromate (accurate to 0.0002g) dried at 105℃~110℃ to constant weight, dissolve it in a 1000mL volumetric flask with water, dilute to scale, and shake well. The concentration C1 of the potassium dichromate standard solution is calculated according to formula (2): 730
HG/T 2831-1997
K,Cr0,)=
—-Weigh the mass of the standard potassium dichromate, g; where: m-
K2Cr.0,)’s molar mass, g/mol. Potassium dichromate (
5.4.2.9 Ammonium ferrous sulfate standard titration solution: c[Fe(NH) (S()) is about 0.1 mol/L.. (2)
Preparation: Weigh about 40g ammonium ferrous sulfate CFe(NH.)2 (SO.)2*6H.O, dissolve in 300mL (1+8) sulfuric acid solution, and then add 700ml. water. Shake well. The solution should be calibrated before use. Calibration: Use a pipette to transfer 25ml. Potassium dichromate standard solution Place in a 500mL conical flask, add 100mL water and 20mL sulfuric acid mixed acid solution, titrate with ammonium ferrous sulfate standard titration solution until it turns yellow-green, then add 2 drops of N-phenylated o-phenylaminobenzoic acid indicator solution, and continue titrating until the purple-red turns into bright green as the end point. The concentration of ammonium ferrous sulfate standard titration solution ℃ is calculated according to formula (3): C
Where: V,—the volume of potassium dichromate standard solution transferred, mL; Vic
c—the actual volume of potassium dichromate standard solution Concentration, mol/L; — Volume of standard ammonium ferrous sulfate solution consumed in titration, mL. 5.4.3 Analysis steps
·(3)
Weigh about 1g of sample (accurate to 0.0002g), place in a 500mL conical flask, moisten with a small amount of water, add 25mL of phosphoric acid, shake well, heat on an electric stove and boil until the liquid surface is calm and white smoke is slightly emitted (the temperature is 220℃~240℃ at this time). Remove from heat source, immediately add 2g of ammonium nitrate and fully Shake well to drive away the yellow smoke of nitrogen oxides. After cooling slightly (cooling to 50℃~60℃), add 100mL of water, shake thoroughly to dissolve the salts, cool quickly to room temperature, titrate with standard ammonium ferrous sulfate solution until the solution turns light red, add 2 drops of N-phenylated o-phenylaminobenzoic acid indicator solution, and continue titrating until the solution changes from red to bright yellow. 5.4.4 Expression of analysis results
The manganese (Mn) content (X2) expressed as mass percentage is calculated according to formula (4): X =Vc×0. 054 94 ×100
5.494× Vc
Wherein: V—volume of standard ammonium ferrous sulfate solution consumed in titrating the test solution, mL, C—\-actual concentration of standard ammonium ferrous sulfate solution, mol/L.; m
0.054 94-
mass of sample, g;
(4)
mass of manganese in grams equivalent to 1.00mL standard ammonium ferrous sulfate solution cLFe(NH.)2(SO.)2)=1.000mol/L).
5.4.5 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%. 5.5 Determination of iron content
5.5.1 Summary of the method
According to Chapter 2 of GB/T3049.
5.5.2 Reagents and materials
According to Chapter 3 of GB/T3049.
5.5.3 Instruments and equipment
According to Chapter 4 of GB/T3049.
5.5.4 Analysis steps
5.5.4.1 Drawing of working curve
HG/T 2831--1997
According to the provisions of 5.3 of GB/T3049, use a 3 cm absorption cell and the corresponding iron standard solution to draw the working curve. 5.5.4.2 Determination
Use a pipette to transfer 1.0mL of test solution A (5.3.4.1) and test blank solution (5.3.4.2) into 100mL beakers respectively, add 40mL of water, adjust the pH to close to 2 with ammonia solution (check the pH with precision test paper), transfer all the solutions into two 100mL volumetric flasks, add 2.5mL of ascorbic acid solution, 10mL of buffer solution, and 5mL of o-phenanthroline solution respectively, dilute with water to the scale, and shake the hook. Select a 3cm absorption cell, adjust the absorbance of the spectrophotometer to zero at 510nm, and measure the absorbance with water as reference. According to the absorbance of the test solution and the test blank solution, the mass of iron can be checked from the working curve. 5.5.5 Expression of analysis results
The iron (Fe) content (X) expressed as mass percentage is calculated according to formula (5): X3
mi -mo
m×500
50 × (ml - mo)
Wherein: m—-the mass of iron in the test solution obtained from the working curve, mg; mo—the mass of iron in the test blank solution obtained from the working curve, mg; m—-the mass of the sample weighed in 5.3.4.1, g. 5.5.6 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 0.03%. 5.6 Determination of sulfate content
5.6.1 Summary of method
In the hydrochloric acid medium, sulfate ions and barium ions generate white fine barium sulfate precipitates, which are turbidometrically compared with the standard turbidimetric solution. 5.6.2 Reagents and materials
5.6.2.1 Hydrochloric acid solution: 1+1;
5.6.2.2 Barium chloride solution: 250g/I.; 5.6.2.3 Sulfate standard solution: 1mL contains 0.1mgSO4; 5.6.2.4 Manganese dihydrogen phosphate solution without sulfate: ()
Preparation: Weigh 25g sample (accurate to 0.01g), add 500mL water and hydrochloric acid solution until the sample is completely dissolved, add 25ml. Barium chloride solution, dilute with water to 1000mL and stir evenly. Let stand for 12h and filter for use (each 40mL solution is equivalent to 1g sample). 5.6.3 Analysis steps
Weigh 1.0g sample (accurate to 0.01g), place in a 100mL colorimetric tube, 40mL water and 1mL hydrochloric acid solution (filter if necessary). Add 1ml of chlorinated sodium chloride solution, dilute to 50ml, shake well, and let stand for 30min. Its turbidity shall not be greater than that of the standard turbidity solution. The standard turbidity solution is taken with a pipette: 5ml of the superior product and 7ml of the first-class product sulfate standard solution are placed in 100ml colorimetric tubes respectively, and 40ml of sulfate-free manganese dihydrogen phosphate solution is added to each and treated in the same way as the sample solution. 5.7 Determination of hydrolysis insoluble matter content
5.7.1 Summary of the method
After dissolving the sample in water, filter, wash, dry and weigh. 5.7.2 Instruments and equipment
5.7.2.1 Glass sand crucible: pore size 5μm~15μm; 5.7.2.2 Electric oven: the temperature can be controlled at 105℃~110℃. 5.7.3 Analysis steps
Weigh about 3g of sample (accurate to 0.0002g), place in a 150ml beaker, add 75ml of water until the sample dissolves, heat in a boiling water bath for 30min, filter while hot using a glass crucible that has been dried to constant weight at 105℃~110℃, wash with hot water 3~4 times, 30ml732
HG/T 2831--1997
water each time, place the glass crucible in an oven at 105℃~110℃ and dry for 45min, take out and place in a desiccator to cool and weigh. Collect the filtrate and washings in a 250ml volumetric flask, dilute to scale with water, and shake well. This is test solution B. Used for the determination of total acidity.
Description of analysis results
The hydrolysis insoluble matter content (X) expressed as mass percentage is calculated according to formula (6): X4=ml×100
Wherein: m,
-mass of the residue after drying, g;
m-mass of the sample, g.
5.7.5 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 0.1%. 5.8 Determination of total acidity
5.8.1 Summary of method
The number of mL of standard sodium hydroxide solution c (NaOH, 0.1 mol/L) consumed in titrating 0.3 g of the sample in water. 5.8.2 Reagents and materials
5.8.2.1 Phenolphthalein ethanol indicator solution: 10 g/L; 5.8.2.2 Sodium hydroxide standard titration solution: c(NaOH) is about 0.1 mol/L. 5.8.3 Analysis steps
. (6)
Use a pipette to transfer 25 mL of test solution B (5.7.3) into a 250 mL conical flask, add 20 mL of water, add 2 drops of phenolphthalein indicator solution, and titrate with sodium hydroxide standard titration solution until it turns slightly red and does not fade for 30 seconds, which is the end point. 5.8.4 Expression of analysis results
The total acidity (Xs) in manganese dihydrogen phosphate is calculated according to formula (7): Xs = Ve ×3
30×Vc
The volume of sodium hydroxide standard titration solution consumed in titration, mL; where: V——
The actual concentration of sodium hydroxide standard titration solution, mol/L; m——The mass of the sample weighed in -5.7.3, g; 3——Coefficient.
5.8.5 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 0.1 titer. 5.9 Determination of heating loss
5.9.1 Instruments and equipment
5.9.1.1 Weighing bottle: @50mm×30mm;
5.9.1.2 Electric oven: The temperature can be controlled at 105℃~~110℃. 5.9.2 Analysis steps
. (7)
Use a weighing bottle that has been dried to constant weight at 105℃~110℃ in advance to weigh 2g of the drug sample (accurate to 0.0002g), place it in an oven, dry it at 105℃~~110℃ to constant weight, take it out and place it in a desiccator to cool and weigh it. 5.9.3 Expression of analysis results
The heating loss (X.) expressed as mass percentage is calculated according to formula (8): X. =m=m×100
Where: m-mass of the sample after drying, g
m-mass of the sample, g.
5.9.4 Allowable difference
HG/T2831-1997
Take the arithmetic mean of the parallel determination results as the determination result. The absolute difference of the parallel determination results shall not exceed 0.2%. 6 Marking, packaging, transportation and storage
6.1 The packaging bags of industrial manganese dihydrogen phosphate should be firmly and clearly marked, including: manufacturer name, factory address, product name, trademark, grade, net weight, batch number or production date and this standard number, as well as the "wet-afraid" mark specified in GB191. 6.2 Each batch of industrial manganese dihydrogen phosphate shipped out of the factory should be accompanied by a quality certificate. The contents include: manufacturer name, factory address, product name, trademark, grade, net weight, batch number or production date, proof that the product quality complies with this standard and this standard number. 6.3 Industrial manganese dihydrogen phosphate can be packaged in polypropylene woven bags lined with plastic bags. Woven bag packaging: The inner packaging is made of polyethylene or polyvinyl chloride plastic film bags with a thickness of not less than 0.08mm, The outer packaging adopts polypropylene woven bags, and its performance and inspection methods shall comply with the relevant provisions of GB8946B. The net weight of each bag of this product is 25kg or 50kg. Woven bag packaging: When packaging, put the industrial manganese dihydrogen phosphate into a polypropylene woven bag lined with polyethylene or polyvinyl chloride plastic film bags, exhaust the remaining air in the bag, tie the bag mouth of the inner bag twice with a string, tie it tightly, and sew the outer bag with a sewing machine at a distance of not less than 17mm from the upper end of the bag, with a stitch length of 6mm to 7mm, neat stitches, and uniform stitch length. There should be no leaking or skipping. 6.4 Industrial manganese dihydrogen phosphate should be covered during transportation to prevent sun exposure, rain, and packaging damage, and must not be inverted. 6.5 Industrial manganese dihydrogen phosphate should be stored in a ventilated and dry warehouse to prevent sun exposure and moisture. 7341 The packaging bags of industrial manganese dihydrogen phosphate should have firm and clear markings, including: manufacturer name, factory address, product name, trademark, grade, net weight, batch number or production date and this standard number, as well as the "wet-afraid" mark specified in GB191. 6.2 Each batch of industrial manganese dihydrogen phosphate shipped out of the factory should be accompanied by a quality certificate. The contents include: manufacturer name, factory address, product name, trademark, grade, net weight, batch number or production date, proof that the product quality complies with this standard and this standard number. 6.3 Industrial manganese dihydrogen phosphate can be packaged in polypropylene woven bags lined with plastic bags. Woven bag packaging: The inner packaging is made of polyethylene or polyvinyl chloride plastic film bags with a thickness of not less than 0.08mm, and the outer packaging is made of polypropylene woven bags. Bags, their performance and inspection methods should comply with the relevant provisions of GB8946B. The net weight of each bag of this product is 25kg or 50kg. Woven bag packaging: When packaging, put the industrial manganese dihydrogen phosphate into a polypropylene woven bag lined with polyethylene or polyvinyl chloride plastic film bags, exhaust the remaining air in the bag, tie the bag mouth of the inner bag twice with a string, tie it tightly, and sew the outer bag with a sewing machine at a distance of not less than 17mm from the upper end of the bag, with a stitch length of 6mm to 7mm, neat stitches, and uniform stitch length. There should be no leaking or skipping. 6.4 Industrial manganese dihydrogen phosphate should be covered during transportation to prevent sun exposure, rain, and packaging damage, and should not be inverted. 6.5 Industrial manganese dihydrogen phosphate should be stored in a ventilated and dry warehouse to prevent sun exposure and moisture. 7341 The packaging bags of industrial manganese dihydrogen phosphate should have firm and clear markings, including: manufacturer name, factory address, product name, trademark, grade, net weight, batch number or production date and this standard number, as well as the "wet-afraid" mark specified in GB191. 6.2 Each batch of industrial manganese dihydrogen phosphate shipped out of the factory should be accompanied by a quality certificate. The contents include: manufacturer name, factory address, product name, trademark, grade, net weight, batch number or production date, proof that the product quality complies with this standard and this standard number. 6.3 Industrial manganese dihydrogen phosphate can be packaged in polypropylene woven bags lined with plastic bags. Woven bag packaging: The inner packaging is made of polyethylene or polyvinyl chloride plastic film bags with a thickness of not less than 0.08mm, and the outer packaging is made of polypropylene woven bags. Bags, their performance and inspection methods should comply with the relevant provisions of GB8946B. The net weight of each bag of this product is 25kg or 50kg. Woven bag packaging: When packaging, put the industrial manganese dihydrogen phosphate into a polypropylene woven bag lined with a polyethylene or polyvinyl chloride plastic film bag, exhaust the remaining air in the bag, tie the bag mouth of the inner bag twice with a string, tie it tightly, and sew the outer bag with a sewing machine at a distance of not less than 17mm from the upper end of the bag, with a stitch length of 6mm to 7mm, neat stitches, and uniform stitch length. There should be no leaking or skipping. 6.4 Industrial manganese dihydrogen phosphate should be covered during transportation to prevent sun exposure, rain, and packaging damage, and must not be inverted. 6.5 Industrial manganese dihydrogen phosphate should be stored in a ventilated and dry warehouse to prevent sun exposure and moisture. 734
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