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In this study, ionic liquid (IL) 1-butyl-3-methylimidazolium hexafluorophosphate ([BMIM][PF 6 ])-modified magnetic graphene oxide (MGO-IL) was prepared for the first time, and was used to adsorb and remove arsenic (As(Ⅲ) and As(V)) ions from aqueous solution. MGO-IL was characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, thermogravimetric analysis, and magnetization curves. Effects of ionic liquid type, solution pH, initial arsenic concentration and contact time on the adsorption performance of MGO-IL for As(Ⅲ) and As(V) were studied. The experimental results showed that the adsorption equilibrium was achieved within 30 min, with maximum adsorption capacities of 160.65 mg g−1 for As(Ⅲ) and 104.13 mg g−1 for As(V), respectively, and MGO-IL could be rapidly isolated from solution by applying a magnetic field. MGO-IL was reused for 5 times, without marked decrease in its adsorption capacities. Moreover, common coexisting anions did not interfere with the absorption of As(Ⅲ) and As(V). Compared with MGO, the sorption quantities of MGO-IL for As(Ⅲ) and As(V) were greatly enhanced, and the equilibrium time was significantly reduced. Therefore, MGO-IL can potentially serve as an excellent adsorbent for the simultaneous separation and removal of As(Ⅲ) and As(V) from water. Image 1 • MGO-IL was prepared and characterized. • MGO-IL exhibited high adsorption capacities for As(Ⅲ) and As(Ⅴ). • Adsorption of As(Ⅲ) and As(Ⅴ) onto MGO-IL was fast. • MGO-IL showed good anti-interference ability and reusability. • MGO-IL can be used for removal of As(III) and As(Ⅴ) from aqueous solution. Capsule: Ionic liquid-modified magnetic graphene oxide for efficient removal of As(Ⅲ) and As(V) ions from aqueous solution. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • A multi-templates MIP was prepared by surface molecularly imprinting technology. • The MIP showed remarkable adsorption capacity, kinetics and reusability. • The MIP exhibited good adsorption selectivity towards alkylphenols. • The MIP was used as the MSPE adsorbent for alkylphenols detection. • Real water samples were analyzed with satisfactory results. Abstract A novel multi-templates molecularly imprinted polymer (MIP) was prepared on the surface of mesoporous silica coated magnetic graphene oxide (MGO@mSiO 2), and applied for the rapid and selective detection of alkylphenol compounds including bisphenol A (BPA), 4-tert-octylphenol (4-tert-OP) and 4-nonylphenol (4-NP) in water. The synthesized composite was characterized by Fourier transform infrared spectrometer, vibrating sample magnetometer, transmission electron microscopy and Brunauer-Emett-Teller surface area analyzer. The MIP showed high adsorption capacity, good selectivity and fast kinetic for these alkylphenols. The maximum adsorption capacities of the MIP for BPA, 4-tert-OP and 4-NP were 16.81, 35.97 and 61.73 mg g−1, respectively, which were significantly higher than those of the non-molecularly imprinted polymer (NIP) due to the imprinting effect. The adsorption of alkylphenols reached equilibrium within 30 min, and followed pseudo-second-order kinetic model and Langmuir model well. The MIP exhibited good sorption selectivity towards BPA, 4-tert-OP and 4-NP, and could be reused 5 times. Furthermore, a new method for ultrasensitive determination of BPA, 4-tert-OP and 4-NP in water by high performance liquid chromatography was developed, using MIP-based magnetic solid-phase extraction coupled with dispersive liquid-liquid microextraction. Under the optimum conditions, the limits of detection (LODs) for BPA, 4-tert-OP and 4-NP were 0.013, 0.010 and 0.010 μg L−1, respectively. The proposed method was used to the detection of BPA, 4-tert-OP and 4-NP in real water samples, with spiked recoveries of 81.5–104.1% and relative standard deviations (RSDs) of 1.0–7.6%, indicating the multi-templates MIP could be a promising adsorbent for separation and analysis of alkylphenols. [ABSTRACT FROM AUTHOR]