مشخصات پژوهش

In this research a novel sorbent based on reinforcement of montmorillonite (MMT) [1,2] into polypyrrole-polyamide (PPy-PA) hybrid was fabricated by in situ oxidative polymerization of polypyrrole into MMT/PA mixture. The prepared nanocomposite was coated onto stainless steel substrate by solvent exchange method to form a thin layer of nanocomposite. The PA and MMT/PPy/PA coated stir bars were characterized using scanning electron microscopy (SEM), energy dispersive X-ray spectroscomy (EDX), X-ray diffraction (XRD) and Fourier transform infrared sepectroscopy (FTIR). The prepared MMT/PPy/PA nanocomposite-based stir bar was applied as an extraction device for stir bar sorptive extraction (SBSE) of organophosphorous pesticides (OPPs) as model compounds including chlorpyrifos, ethion and phosalone in river water samples in combination with gas chromatography-flame ionization detector (GC-FID) detection. The effect of MMT amount in the nanocomposite and also the effect of PPy incorporation into PA on the extraction capability of the coating were investigated. Accordingly, the 15 % MMT doping level has led to higher extraction capability. Furthermore, it was found that PPy hybridation into nanocomposite has significant effect in improving the extraction capability of the coating. Important factors influencing the extraction and desorption processes including extraction time, salt content, pH, desorption solvent, its volume and desorption time were studied and optimized using response surface methodology (RSM) applying central composite design (CCD) [4]. The developed method was successfully applied to determine selected OPP compounds in two river water samples and high relative recovery percentages were resulted. References