Facile large scale fabrication of magnetic carbon nano-onions for efficient removal of bisphenol A

- Novel magnetic carbon nano-onions (MCNOs) were fabricated in gram scale.
- The MCNOs showed high adsorption capacity toward bisphenol A (BPA).
- The influences of initial concentration of BPA, solution pH, and adsorption time were investigated.
- The adsorbents are easily regenerated and recycled by using an external magnet.

In this work, a scalable and cost-effective approach was developed for the synthesis of magnetic carbon nano-onions (MCNOs) by using iron (III) acetylacetonate modified candle as the raw materials. The candle soot was collected from the burning candle and then subjected to calcination at 800 °C under N2 atmosphere. The obtained MCNOs were further applied as adsorbent for the removal of bisphenol A (BPA) from aqueous solutions. Adsorption of BPA onto the MCNOs was investigated with the influence of initial concentration of BPA, solution pH, and adsorption time. The results demonstrated the adsorption of BPA onto the MCNOs was almost not affected by pH in the range from 5-9. The adsorption isothermal and kinetic's data were better fitted by Langmuir isotherm and pseudo-second-order kinetic model, respectively. Moreover, the MCNOs are easily recycled by using and external magnet and regenerated by simply methanol washing. The results present here not only provide a novel synthetic approach toward low-cost nanocarbons but also revealed the great application potential of the MCNOs for the removal of endocrine disrupting compounds from aqueous solution.

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