A flow injection knotted reactor suction elution method coupled with flame atomic absorption spectrometry for the determination of trace lead and zinc in water

A new flow injection(FI) pre-concentration system through suction elution in a knotted reactor is developed for the determination of trace lead and zinc by flame atomic absorption spectrometry.In this method,the eluting process depends on the suction of the peristaltic pump,but not on the pushing force,which notably decrease the dispersion of the analyte.With preconcentration of 60 s at a flow rate of 6.0 mL/ min,the enhancement factor(EF) of Pb and Zn were found as 32 and 40,respectively.The detection limits were 8.1 μg/L and 0.44 μg/L and the sample output rate was 40 samples/hour.For parallel determination of 200 μg/L Pb and 10 μg/L Zn for eleven times,the relative standard deviations(RSDs) found were 2.6 % and 2.9 %,repectively.This method is especially suitable for determination of low content of lead and zinc in environmental water.