A magnetic adsorbent based on salicylic acid-immobilized magnetite nano-particles for pre-concentration of Cd(II) ions

In this research,an eco-friendly magnetic adsorbent based on Fe_(3)O_(4)/salicylic acid nanocomposite was fabricated using a facile one-pot co-precipitation method.The crystalline and morphological characterization of the prepared nanocomposite was performed by field emission scanning electron microscopy,X-ray diffraction,and Fourier transform infrared spectroscopy.The nanocomposite was employed as a magnetic solid-phase extraction agent for separation of Cd(II)ions from synthetic solutions.Some experimental factors affecting the extraction efficiency were investigated and optimized.Following elution with acetic acid(pH 3.5),the pre-concentrated analyte was quantified by flame atomic absorption spectrometry.In optimal conditions,a linear calibration graph was achieved in the concentration range of 0.2–30 ng·mL^(−1) with a determination coefficient(R^(2))of 0.9953.The detection limit,the enhancement factor,inter-and intra-day relative standard deviations(for six consecutive extractions at the concentration level of 10 ng·mL^(−1))were 0.04 ng·mL^(−1),100,2.38%and 1.52%,respectively.To evaluate the accuracy of the method,a certified reference material(NIST SRM 1643e)was analyzed,and there was a good agreement between the certified and the measured values.It was successfully utilized to determine cadmium in industrial wastewater samples and the attained relative recovery values were between 96.8%and 103.2%.