Multifunctional HKUST-1-3D-printed device for the simultaneous extraction of hydrocarbons and dyes from water

Abstract

Herein, we report a MOF polymer coating and in-situ growth mixed strategy to fabricate a multifunctional floating 3D printed device for simultaneous hydrocarbon and dye removal. Due to the superhydrophobic properties (water contact angle = 151o) of the upper part of the device, it was applied for the removal of oil from water, obtaining excellent separation efficiency (from 90 to 98.6 %) for n-hexane, decane, dodecane and hexadecane. In addition, this part of the device showed excellent reusability, maintaining its separation efficiency of hexane/water above 95 % with a relative standard deviation of 1.0 % after 25 consecutive extraction cycles. The lower part of the multifunctional device, coated with HKUST-1 synthesized by in-situ growth, was tested for methylene blue dye removal, demonstrating fast kinetics adsorption (percentage of removal higher than 90 % in 2 h) due to the combination of electrostatic and π-π interactions between HKUST-1 and the dye. Furthermore, this 3D support showed high versatility, exceeding a 92 % extraction capacity for various dyes (malachite green, crystal violet and methyl violet), with the advantage of being easily regenerated several times by a simple regrowth procedure. Finally, the complete 3D-modified device was tested for the simultaneous extraction of hydrocarbons and dyes from real groundwater sample with excellent results.