Quantitative determination of anionic surfactant in enhanced oil recovery

In this article,a new method was confirmed to analyze quantitatively the anionic surfactant concentration in EOR by visible spectrophotometry.The best conditions of the method are the followings: maximum wavelength 630 nm;cationic surfactant standard solution(1.0×10-4 mol/L)20mL;buffer indicator 10mL;waiting time 2 hours;temperature 25 ℃.The best concentration range for the anionic surfactant is half of that for the cationic surfactant.The liner correlation coefficient of the working curve is 0.999 72.Many common used anionic surfactants in EOR were measured,the liner correlation coefficients are all(bigger than) over 0.990 00.So,this method can be applied widely.