Ultrasound-assisted emulsification–microextraction followed by inductively coupled plasma–optical emission spectrometry was utilized for simultaneous pre-concentration and trace detection of lead,bismuth,and iron in...Ultrasound-assisted emulsification–microextraction followed by inductively coupled plasma–optical emission spectrometry was utilized for simultaneous pre-concentration and trace detection of lead,bismuth,and iron in water samples.Disodium N,N-bis(salicylidene)ethylenediamine and trichloroethylene were used as chelating agent and extraction solvent,respectively.The parameters of interest were volume of extraction solvent,temperature,and concentrations of salt and chelating agent.A fractional factorial design was developed to identify these parameters and how they vary with one another.The results demonstrated that the concentrations of salt and chelating agent affected extraction efficiency.Subsequently,a central-composite design was used to acquire optimum levels of effective parameters.The optimal conditions were 160.7 mg L^(−1) and 1.77%(w/v)for concentration of chelating agent and salt,respectively.The linear dynamic ranges were determined to be 1–1000μg L^(−1) for Pb and Bi,and 10–1000μg L^(−1) for Fe.The correlation coefficient(R2)was 0.990–0.995.The limits of detection were 0.54–0.78μg L^(−1).The relative standard deviation(concentration=200μg L^(−1),n=8)was in the range of 2.0–4.3%.This method was successfully applied for the trace detection of Pb,Bi,and Fe in freshwater samples of waterfall and spring and satisfactory relative recoveries(96.2–99.6%)were obtained.展开更多
文摘Ultrasound-assisted emulsification–microextraction followed by inductively coupled plasma–optical emission spectrometry was utilized for simultaneous pre-concentration and trace detection of lead,bismuth,and iron in water samples.Disodium N,N-bis(salicylidene)ethylenediamine and trichloroethylene were used as chelating agent and extraction solvent,respectively.The parameters of interest were volume of extraction solvent,temperature,and concentrations of salt and chelating agent.A fractional factorial design was developed to identify these parameters and how they vary with one another.The results demonstrated that the concentrations of salt and chelating agent affected extraction efficiency.Subsequently,a central-composite design was used to acquire optimum levels of effective parameters.The optimal conditions were 160.7 mg L^(−1) and 1.77%(w/v)for concentration of chelating agent and salt,respectively.The linear dynamic ranges were determined to be 1–1000μg L^(−1) for Pb and Bi,and 10–1000μg L^(−1) for Fe.The correlation coefficient(R2)was 0.990–0.995.The limits of detection were 0.54–0.78μg L^(−1).The relative standard deviation(concentration=200μg L^(−1),n=8)was in the range of 2.0–4.3%.This method was successfully applied for the trace detection of Pb,Bi,and Fe in freshwater samples of waterfall and spring and satisfactory relative recoveries(96.2–99.6%)were obtained.