This standard specifies the technical requirements, test methods, inspection rules and marking, packaging, transportation and storage of neopentyl glycol. This standard applies to neopentyl glycol obtained by condensation of isobutylaldehyde and formaldehyde under alkaline conditions. HG/T 2309-1992 Industrial neopentyl glycol HG/T2309-1992 Standard download decompression password: www.bzxz.net

Chemical Industry Standard of the People's Republic of China
HG/T2309—92
Industrial Neopentyl Glycol
Published on May 17, 1992
Ministry of Chemical Industry of the People's Republic of China
Implemented on January 1, 1993
WChemical Industry Standard of the People's Republic of China
! Neopentyl Glycol
Subject Content and Scope of Application
HG/T2309—92
This standard specifies the technical requirements, test methods, inspection rules and marking, packaging, transportation and storage of neopentyl glycol. This standard applies to neopentyl glycol obtained by condensation of isobutylaldehyde and formaldehyde under alkaline conditions. Molecular formula: CsH1202
Structural formula:
Relative molecular mass: 104.15 (according to the international relative atomic mass in 1989) 2 Reference standards
Chemical reagents Preparation of standard solutions for titration analysis (volume analysis) Preparation of standard solutions for determination of impurities in chemical reagents Preparation of preparations and products used in test methods Chemical reagents
Chemical reagents General method for determination of melting point range GB1250
GB3143
GB6283
GB6678
GB6679
GB8170
3 Technical requirements
Methods for expressing and determining limit valuesColor determination method for liquid chemical products (Hazen unit: platinum-cobalt color number)Determination of water content in chemical products: Karl Fischer method (general method)General rules for sampling of chemical products
General rules for sampling of solid chemical products
Rules for rounding off values
3.1 Appearance: white flaky solid.
3.2 Technical indicators should meet the requirements of the following table.
Approved by the Ministry of Chemical Industry of the People's Republic of China on May 17, 1992, and implemented on January 1, 1993
W.bzsoso.coD Item
70% aqueous solution Chroma (in Hazen units) Hydroxyl content, %
Acid content (in acetic acid), %
Melting point range, ℃
Water content, %
4 Test method
HG/T2309—92
First-class product
123~130
Qualified product
118~130
The reagents and water used in this standard refer to analytical pure reagents and distilled water or water of corresponding purity unless otherwise specified. 4.1 Determination of chromaticity of 70% aqueous solution
4.1.1 Sample colorimetric solution: sample + water = 7 + 3 (m + m). 4.1.2 Analysis steps
Perform according to GB3143.
4.2 Determination of hydroxyl content
4.2.1 Acetic anhydride-pyridine method (arbitration method) 4.2.1.1 Principle of the method
Under the catalytic action of pyridine, the hydroxyl group of neopentyl glycol undergoes quantitative acetylation with acetic anhydride to generate ester and acetic acid. The hydroxyl content is calculated by the amount of acetic anhydride consumed in the reaction.
4.2.1.2 Reagents and solutions
Standard sodium hydroxide titration solution: c (NaOH) = 1 mol/L: a.
Phenolic indicator solution: 10 g/L:
Acetylation solution: acetic anhydride + pyridine = 1 + 9 (V + V). This solution is prepared when used. c.
4.2.1.3 Apparatus
Constant temperature water bath or glycerol bath and general laboratory instruments. 4.2.1.4 Experimental steps
Weigh 0.8g (accurate to 0.0002g) of the finely ground sample and place it in a 250mL dry ground-mouth conical flask. Use a pipette to accurately add 20mL of acetylation solution and shake well. Install a ground-mouth condenser and place it in a water bath or glycerol bath (temperature is 90-100℃), heat and reflux for 1h (shake during heating), take out the conical flask and cool it to room temperature in a cold water bath below 5℃, rinse the condenser with 20mL of water, remove the conical flask and add 2-3 drops of phenol crisp indicator, drip with sodium hydroxide standard solution until it turns slightly red, and do a blank test at the same time. 4.2.1.5 Calculation of analysis results
The mass percentage of hydroxyl X is calculated according to formula (1): _c(Vo-V)X0.01701
-actual concentration of sodium hydroxide standard titration solution, mol/L; where: c-
-volume of sodium hydroxide standard titration solution consumed by blank, mL; Vo
WHG/T230992
V-volume of sodium hydroxide standard titration solution consumed by sample, mL; m——mass of sample, g;
0.01701——mass of hydroxyl expressed in grams equivalent to 1.00mL sodium hydroxide standard titration solution [c(Na0H)=1.000mol/L].
Take the arithmetic mean as the determination result.
4.2.1.6 Permissible difference
The difference between the results of two parallel determinations shall not be greater than 0.2%. 4.2.2 Acetic anhydride-sodium acetate method
4.2.2.1 Principle of the method
Under the catalytic action of sodium acetate, the hydroxyl groups of neopentyl glycol react with acetic anhydride to quantitatively acetylate to form esters and acetic acid. The hydroxyl content is calculated by the amount of acetic anhydride consumed.
4.2.2.2 Reagents and solutionsbZxz.net
Sodium acetate, anhydrous;
Acetic anhydride;
Phenolphthalein indicator solution: 10g/L;
Standard sodium hydroxide titration solution: c(NaOH)=1mol/L. 4.2.2.3
Instruments or equipment
General laboratory instruments;
Flat-plate electric furnace: 500 or 800 W;
Straight tube air condenser;
Voltage regulator: 1 kV;
Microburette: 3 mL;
Hard glass test tube: 50 mL.
4.2.2.4 Analysis steps
Weigh about 0.7g (accurate to 0.0002g) of the finely ground and mixed sample and place it in a dry test tube, add 0.4g (accurate to 0.1g) of anhydrous sodium acetate and use a microburette to add 2.000mL of acetic anhydride, install an air condenser, place the test tube on a preheated electric stove (adjust the voltage regulator to 100-120V and preheat for 10min), slowly heat to a slight boil, and after the solid matter in the tube disappears completely (except for the blank), remove the test tube and cool it to near room temperature, wash the reactant with 40-50mL of water into a 250mL conical flask, place it for 30min, add 2 drops of phenolphthalein, and titrate with a sodium hydroxide standard titration solution until it turns slightly red and remains unfaded for 30s as the end point. Perform a blank test at the same time.
Calculation of analysis results
The mass percentage of hydroxyl X2 is calculated according to formula (2): X2 = (Vo-V) X0. 017 01 x
Wherein: c—
-actual concentration of sodium hydroxide standard titration solution, mol/L; V. —volume of sodium hydroxide standard titration solution consumed by blank, mL; V—volume of sodium hydroxide standard titration solution consumed by sample, mL; m
-mass of sample, g;
0.01701—mass of hydroxyl expressed in grams equivalent to 1.00mL sodium hydroxide standard titration solution [c (Na0H) = 1.000mol/L].
Take the arithmetic mean as the determination result.
4.2.2.6 Allowable difference
HG/T230992
The difference between the results of two parallel determinations shall not be greater than 0.2%. 4.3 Determination of acid content
4.3.1 Principle of the method
According to the principle of neutralization reaction, the acid content in neopentyl glycol is quantified with sodium hydroxide standard titration solution using phenolphthalein as indicator solution. 4.3.2 Reagents and solutions
a. Phenolyl indicator solution: 10g/L;
b. Sodium hydroxide standard titration solution: c (NaOH) = 0.02mol/L. 4.3.3 Instruments
General laboratory instruments.
4.3.4 Analysis steps
Weigh about 5g of sample (accurate to 0.01g) and place it in a conical flask, add 50mL of carbon dioxide-free water and 2 drops of phenolyl indicator solution, and titrate with sodium hydroxide standard titration solution until it turns slightly red, and keep it for 15s without fading as the end point. Perform a blank test at the same time. 4.3.5 Calculation of analysis results
Mass percentage of acid (in terms of acetic acid) X: Calculate according to formula (3): _c(V-Vo)X0.06005
Wherein: c is the actual concentration of the sodium hydroxide standard titration solution, mol/L; Vo is the volume of the sodium hydroxide standard titration solution consumed by the blank, mL; V is the volume of the sodium hydroxide standard titration solution consumed by the sample, mL;
0.06005 is the mass of the sample, g;
0.06005 is the mass of the sample with 1.00mL of sodium hydroxide standard titration solution [c(Na0H)=1.000mo1/L】equivalent to the mass of acetic acid expressed in grams.
Take the arithmetic mean as the determination result.
4.3.6 Allowable difference
The difference between the results of two parallel determinations shall not be greater than 0.005%. 4.4 Determination of melting point range
Under the condition that the room temperature does not exceed 25℃, grind the sample into powder, place it in a silica gel dryer and dry it for 24 hours, and then perform it in accordance with the provisions of GB617.
Take the arithmetic mean as the determination result.
4.4.1 Allowable difference
The difference between the average values ​​of the initial melting temperature and the final melting temperature measured twice shall not exceed 1℃. 4.5 Determination of moisture
Weigh 11.5g of sample (accurate to 0.0002g), and perform other operations in accordance with the provisions of GB6283. Take the arithmetic mean as the determination result.
4.5.1 Allowable difference
The difference between two determination results shall not be greater than 0.05%. 5 Inspection rules
5.1 Neopentyl glycol products shall be inspected by the quality inspection department of the manufacturer, and the manufacturer shall ensure that all products leaving the factory meet the requirements of this standard.
5.2 Each batch of products leaving the factory shall be accompanied by a quality certificate in a certain format, including: manufacturer name, product name, grade, batch number, net weight, production date, product quality and standard number. 5.3 The user unit has the right to accept in accordance with the provisions of this standard. 5.4 The output of each kettle is considered as a batch, and sampling shall be carried out in accordance with the provisions of GB6678 and GB6679, and the sampling volume shall not be less than 250g. 5.5 Mix the samples and pack them into two clean and dry wide-mouth bottles with lids. Paste labels with product name, sampling date, sampler name and batch number. One bottle is for analysis and inspection, and the other bottle is sealed for two months for future reference. 5.6 If one of the indicators in the test results does not meet the requirements of this standard, re-samples should be taken from two bags for re-inspection. If even one of the re-inspection results does not meet the requirements, the entire batch of products is unqualified. 5.7 When the supply and demand parties have disputes over product quality and need arbitration, the arbitration institution can be selected by negotiation between the two parties. Arbitration verification shall be carried out in accordance with the provisions of this standard.
5.8 The judgment of the test results shall be carried out according to the comparison method of rounded values ​​of GB1250, and the rounding shall be carried out according to GB8170. 6 Marking, packaging, transportation and storage
6.1 The packaging bag shall indicate: manufacturer name, product name, trademark, batch number, this standard number, net weight and moisture-proof mark. 6.2 Neopentyl glycol products should be packed in plastic film bags inside and four-layer kraft paper bags and plastic woven bags or other packaging materials that can ensure product quality outside. The net weight of each bag is 25kg.
6.3 When transporting neopentyl glycol, it should be loaded in a covered truck or cabin. The truck or cabin should be clean and dry. 6.4 Neopentyl glycol should be stored in a light-proof, dry and clean warehouse and should not be piled in the open air. Additional remarks:
This standard was proposed by the Science and Technology Department of the Ministry of Chemical Industry of the People's Republic of China. This standard is under the jurisdiction of the Beijing Chemical Research Institute of the Ministry of Chemical Industry. This standard was drafted by the Additive Factory of Jilin Chemical Industry Company. The main drafter of this standard is Chen Shulan.
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