FTIR测定在用润滑油碱值的快速方法

Study of Appling FTIR to Determine Base Number of In-use Lubricants

碱值是监控润滑油质量变化的常规指标，表示内燃机油的清净性与中和能力，通过测定碱值可为合理换油提供依据。利用傅里叶变换红外光谱快速测定在用润滑油碱值，它与标准方法相比，具有速度快，化学试剂用量小，精密度高，操作方便等显著特点。研究结果表明所建方法与国家标准方法的测定结果之间具有很好的一致性，测定结果的相对标准偏差小于5％。

The base number （BN） is applied to inspect the usual index of lubricant quality change. It represents lustration and neutralization capacity of oil in gas engine. The measurements are commonly used to characterize in-use oil in terms of oxidative status or reserve alkalinity. FTIR technology is adopted in some ASTM methods, and is applied to the study of lubricant＇ s base number （BN） in this paper. Compared with the standard method, the proposed method is characterized with rapidity, simplicity, minimal reagent use and no chemical pollutions to the environment. The experimental results shows that the established method gives better repeatability and accuracy ,and has a maximum relative standard error less than 5%.