GB/T 7383-2007
Non-ionic surface active agents.Determination of hydroxyl valu (English Version)

Standard No.

GB/T 7383-2007

Language

Chinese, Available in English version

Release Date

2007

Published By

General Administration of Quality Supervision, Inspection and Quarantine of the People‘s Republic of China

Status

Be replaced 2021-07

Replace By

GB/T 7383-2020

Latest

GB/T 7383-2020

Replace

GB/T 7384-1996 GB/T 7383-1997

Scope

This standard specifies the determination of the hydroxyl value of nonionic surfactants. This standard is applicable to the hydroxyl value of aliphatic and cycloaliphatic polyalkoxy compounds (especially the hydroxyl value of adducts of ethylene oxide, propylene oxide and their mixtures of primary fatty alcohols, alkylphenols and fatty acids) ) is suitable for the determination of hydroxyl value in the range of 10 to 1 000. The phthalic anhydride method is especially suitable for the determination of the hydroxyl value of ethylene oxide, propylene oxide and their mixed adducts of primary and secondary fatty alcohols, alkylphenols and fatty acids. The acetic anhydride method is especially suitable for the determination of the hydroxyl value of ethylene oxide adducts of primary and secondary fatty alcohols, alkylphenols and fatty acids, but not for the determination of the hydroxyl value of propoxylated products. Substances that may interfere are as follows: ——Primary and secondary amines, amides, tertiary alcohols, thiols and epoxides produce side reactions that affect the accuracy of the method. - Long chain aliphatic acids and esters form more stable anhydrides than phthalic anhydride and acetic anhydride, which cannot be completely decomposed at the end of the measurement. ——Other free acids cause interference due to the reaction with sodium hydroxide standard solution; alkalis, including some tertiary amines, cause interference due to the reaction with the generated phthalic acid and acetic acid. Degree for correction (according to GB/T 6365). The presence of epoxides interferes with the determination. If it can be removed by low-temperature vacuum distillation without changing the hydroxyl value, this method is still applicable. The above-mentioned treatment can eliminate free ethylene oxide that interferes with a concentration (mass fraction) higher than 0.5%. Moisture present in the sample will react with phthalic anhydride and acetic anhydride, but this method can still be used if the precautions described in the determination procedure are followed.

GB/T 7383-2007 Referenced Document

• GB/T 11275 Surface active agents.Determination of water content
• GB/T 2384 Dyes intermediates—General method for the determination of melting range*， 2021-12-31 Update
• GB/T 3143 Color determination method of liquid chemicals(Hazen unit--Platinum-cobalt scale)
• GB/T 601 Chemical reagent.Preparations of reference titration solutions*， 2016-10-13 Update
• GB/T 6365 Surface active agents. Determination of free alkalinity or free acidity. Titrimetric method
• GB/T 6372 Surface active agents and detergents. Methods of sample division
• GB/T 8170 Rules of rounding off for numerical values & expression and judgement of limiting values*， 2008-07-16 Update

GB/T 7383-2007 history

• 2020 GB/T 7383-2020 Non-ionic surface active agents—Determination of hydroxyl value
• 2007 GB/T 7383-2007 Non-ionic surface active agents.Determination of hydroxyl valu
• 1997 GB/T 7383-1997 Non-ionic surface active agents--Polyalkoxylated derivatives--Determination of hydroxyl value--Phthalic anhydride method
• 1996 GB/T 7384-1996 Non-ionic surface active agents--Polyethoxylated derivatives--Determination of hydroxyl value--Acetic anhydride method

GB/T 7383-2007 Non-ionic surface active agents.Determination of hydroxyl valu has been changed from GB/T 7384-1996 Non-ionic surface active agents--Polyethoxylated derivatives--Determination of hydroxyl value--Acetic anhydride method.