Determination of Total Nonylphenol Polyethoxylates in Wastewater by Reversed Phase High Performance Liquid Chromatography

摘要

A new method based on SPE-RPLC-FLD was established for the quantitative determination of total NPnEO in wastewater. The sample was pretreated using SPE column of Oasis(R)HLB in Waters Corporation. The column was eluted by 6mL of 90% dichloromethane in methanol(v/v), and the eluting liquid was volatilized to 1ml capacity under breezing nitrogen gas current. The recovery of the process is 99.68%. NPnEO in the sample were separated by the Agilent 1100 LC instrument with ZORBAX Eclipse XDB C-18 liquid chromatography column and with the mobile phase of methanol and water at the flow rate of 1.0mL per min. Gradient elution, the proportion of methanol in water is increased from 70% to 100% gradually at 2.5 % per min, was applied to the process. The oven temperature is set at 23℃, and injection volume is 15μL. The component signals were detected by FLD with 313nm excitation wavelength and 230nm emission wavelength. External standard calibration method was chosen as quantitative analysis. Above 90% recovery of NPnEO was checked up by analyzing real sewage and additional sample using the method, and RSD was below 10%. The LOD of the method for NPnEO was from 0.097 to 0.190 microgrammes per liter. NPnEO concentration of some samples, including raw sewage, effluent of biotreatment system and reclaimed water, was analyzed by this method. The results show that the accuracy and precision of the method were satisfactory.