Synthesis and identification of meta-(4-bromobenzyloxy) benzaldehyde thiosemicarbazone (MBBOTSC) as novel ligand for cadmium extraction by ultrasound assisted-dispersive-ionic liquid-liquid micro extraction method

Abstract

In this research, meta-(4-bromobenzyloxy) benzaldehyde thiosemicarbazone (MBBOTSC) as a novel ligand was synthesized from the reaction between meta-(4-bromobenzyloxy) benzaldehyde and thiosemicarbazide under basic condition in water and ethanol as solvents. Ligand has the ability to chelate ions and therefore, it was used to form a complex and extract ions. Then, the cadmium ions in water and wastewater samples were separated based on MBBOTSC by ultrasound assisted-dispersive-ionic liquid-liquid microextraction method (USA-D-ILLME) before determination by AT-F-AAS. The MBBOTSC ligand was added to the mixture of the ionic liquid/acetone (IL/AC, [OMIM][PF6]) and then injected by syringe to 50 mL of water samples at pH 6-7. The sample was put into the ultrasonic accessory for 5 minutes, after complexation (Ligand-Cd; RS…Cd….RS), the water sample was centrifuged for 3 min for phase separation.  Due to complexation and back-extraction of Cd in liquid phase, the amount of Cd ions in the water samples was determined by AT-F-AAS . In optimized conditions, the Linear ranges and LOD for 50 mL of water samples were obtained 1-36 μg L-1 and 0.3 μg L-1, respectively (Mean RSD= 1.26%). The validation results were successfully achieved by spiking real samples and using ET-AAS.