β-Cyclodextrin capped graphene-magnetite nanocomposite for selective adsorption of Bisphenol-A

K V Ragavan; Navin K Rastogi

doi:10.1016/j.carbpol.2017.03.045

β-Cyclodextrin capped graphene-magnetite nanocomposite for selective adsorption of Bisphenol-A

Carbohydr Polym. 2017 Jul 15:168:129-137. doi: 10.1016/j.carbpol.2017.03.045. Epub 2017 Mar 16.

Authors

K V Ragavan¹, Navin K Rastogi²

Affiliations

¹ Food Engineering Department, CSIR-Central Food Technological Research Institute, Mysore, India; Academy of Scientific and Innovative Research, New Delhi, India. Electronic address: bioragavan@gmail.com.
² Food Engineering Department, CSIR-Central Food Technological Research Institute, Mysore, India; Academy of Scientific and Innovative Research, New Delhi, India. Electronic address: nkrastogi@cftri.res.in.

PMID: 28457432
DOI: 10.1016/j.carbpol.2017.03.045

Abstract

Beta-cyclodextrin capped Graphene-magnetite (G-Fe₃O₄-BCD) nanocomposite was synthesized by ethylenediamine conjugation and used as an adsorbent for selective removal of Bisphenol-A (BPA) in water. Characterization of nanocomposite revealed BCD conjugated to Fe₃O₄ nanoparticles (30-40nm) embedded on graphene. Adsorption process followed Langmuir model and pseudo second order kinetics with an adsorption capacity of 59.6mg/g. It was found to be highly favourable physisorption and endothermic process as indicated by ΔG° (-3.36kJ/mol) and ΔH° (2.08kJ/mol) values at ambient temperatures. The nanocomposite was highly specific towards BPA compared to its analogs, largely driven by host-guest interaction between BCD and BPA. Nanocomposite had a high magnetization of 97emu/g with superparamagnetic property at room temperature which helps in faster separation using an external magnetic field. Nanocomposite can be regenerated with methanol and can be reused without much loss in adsorption efficiency (<10%) after 6 cycles. It has huge potential and application in selective adsorption of target molecules.

Keywords: Bisphenol-A; Graphene nanocomposite; Host-guest interaction; Nano-adsorbent; Specific adsorption; β-Cyclodextrin.