Cloud point-dispersive liquid-liquid microextraction for preconcentration and separation of mercury in wastewater samples by methylsulfanyl thiophenol material

A efficient method based on 4-methylsulfanyl thiophenol (mstp, c7h8s2) and ionic liquid ([bmim][pf6]) was used for mercury (hg) separation and preconcentration from wastewater of petrochemical industries. the 0.01 mile molar of mstp, 80 mg of [bmim][pf6] was diluted with 0.2 ml of ethanol (et 98%). the mixture was injected to 10 ml of wastewater samples, shacked by ultrasonic bath for 5.0 min and cloudy solution was achieved by ionic liquid micelles at ph=7.0. the mercury ions was complexed with mstp and extracted on micelles (il/et) by cloud point dispersive liquidliquid microextraction (cp-dllme) at 50˚c before determined by cold vapor atomic absorption spectrometry (cv-aas). the favorite extraction for mercury with low lod (15 ng l^-1) and good linear rages (0.05- 6.2 μg l^-1) was achieved (rsd<5%). the main parameters such as, ph, sample volumes, amount of mstp, amount of il and ultra-sonic time were optimized. the method validated by spiking samples and certified reference material (crm, nist) in water sample.