میلاد غنی

Herein, a copper-chromium-layered double hydroxide (Cu/Cr-LDH) was synthesized by the co- precipitation method. The Cu/Cr-LDH was intercalated to the Keggin-type polyoxometalate (H 3 PW 12 O 40 ). The modified LDH accommodated in the pores of hollow fiber (HF), to prepare the extracting device for the HF-solid phase microextraction method (HF-SPME). The method was used for the extraction of 4- chlorophenol, 2,4-dichlorophenol, and 2,4,6- trichlorophenol from tap water, river water, and tea sample. The extracted target analytes were quantified via high-performance liquid chromatography-UV detection. The figures of merit of the method such as, linear dynamic ranges (LDRs), limit of detections (LODs) and, limit of quantifications (LOQs), were determined based on the obtained optimum condition. Based on the results, the LDR was between 1 and 500 μg L −1 and r 2 higher than 0.9960. The LODs and LOQs were obtained in the ranges of 0.28–0.36 μg L −1 and 0.92–1.1 μg L −1 , respectively. The relative standard deviations ((RSDs% for inter-and intra-day) of the method for the extraction of target analytes were cal- culated in two different concentrations of (2 and 10 μg L −1 ) and (5 and 10 μg L −1 ) between 3.70% - 5.30% and 3.50% - 5.70%-respectively. The enrichment factors were obtained between 57 and 61. In order to investigate the accuracy of the method, also the relative recovery was obtained, between 93 and 105%. Finally, the proposed method was used for the extraction of the selected analytes in different water and tea samples