[Study on simultaneous determination of nitrate and sulfate in air of residential areas by ion-chromatography].

Objective: A method for determination of nitrate (NO3(-)) and sulfate (SO4(2-)) in air of residential areas by ion-chromatography (IC) was established.

Methods: The anions in aerosol samples collected with filter member were extracted by ultrasonic leaching and separated on IonPac AS11-HC analytical column and IonPac AG11-HC guard column with 20.0 mmol/L potassium hydroxide eluted at 1.00 ml/min, and then detected by DS6 suppressed conductivity detector, with the satisfactory determination of atmospheric nitrate and sulfate.

Results: The correlation coefficient of nitrate and sulfate were greater than 0.9999. The quantification limit of NO3(-) and SO4(2-) was 0.011 microg/m3 and 0.024 microg/m3 respectively. The sampling filter members were divided into four parts equally and spiked, and the recoveries of nitrate and sulfate were 99.6% - 105.6%. The relative standard deviation (RSD) of nitrate and sulfate were less than 3%.

Conclusion: The method was simple, rapid, reproductive and sensitive for determination of nitrate and sulfate in air of residential areas.