电位滴定法测航空润滑油酸值方法研究

Improvement of Potentiometric Titration Method to Measure Lubricating Oils Acid Number

目前石油产品酸值的测定方法电位滴定法对于某些润滑油滴定无终点,则把相应的水性缓冲液的电位作为滴定终点,试验结果重复性较差。本研究提出采用碱性更强的四甲基氢氧化氨盐代替氢氧化钾作为滴定剂,并调整溶剂的配方,使滴定终点产生电位突跃,并就滴定参数对滴定结果的影响规律进行研究,提高了试验效率和试验精度。

At present,the potentiometric titration method for the determination of acid number of petroleum products has no end point in titration for some lubricating oils,so the potential of corresponding aqueous buffer is taken as the eng point of titration,and the experimental results have poor repeatability.In this study,it is proposed to replace potassium hydroxide with ammonium tetramethyl hudroxide,which is more alkaline,as the titrant,and adjust the formula of solvent to make the titration end point produce potential jump.The influence of titration parameters on titration results was studied to improve the efficiency and accuracy of the test.