GB/T 18609-2011 in English

《GB/T 18609-2011原油酸值的测定 电位滴定法》由TC355（全国石油天然气标准化技术委员会）归口，TC355SC10（全国石油天然气标准化技术委员会油气计量及分析方法分会）执行，主管部门为国家标准化管理委员会。

Scope

WARNING: Personnel using this standard should have practical experience in formal laboratory work. This standard does not address all possible safety issues. It is the user's responsibility to take appropriate safety and health measures and ensure compliance with the conditions stipulated in the relevant national laws and regulations. This standard specifies the method for determining the acid value of crude oil by potentiometric titration. This standard is applicable to the determination of acidic components in crude oil that can be dissolved in a mixed solvent of toluene and isopropanol. The dissociation constants of these acidic components in water should be greater than 10^-9; very weak acids with dissociation constants less than 10^-9 will not interfere. Salts with a hydrolysis constant greater than 10^-9 will participate in the reaction. The measuring range of acid value is 0.1mg/g～150mg/g. This standard applies to the determination of crude oil with a mass fraction of water less than 0.5%.