Solvent free synthesis of carbon modified hexagonal boron nitride nanorods for the adsorptive removal of aqueous phase emerging pollutants

Abstract

Contamination of potable water sources by emerging pollutants such as bisphenol-A and paracetamol, etc. is a major ecological concern. The present study delineates the suitability of carbon modified hexagonal boron nitride (HBCN) towards the elimination of Bisphenol-A (BPA) and paracetamol. The HBCN was obtained through an ecofriendly solvent free approach with a surface area of 224.48 m2/g which is about ∼ 11 times higher than commercially available hexagonal boron nitride (C-HBN). The HBCN possess multimodal pore network with an average pore diameter of 2 nm and an isoelectric point at pH: 4.57. The effect of process parameters like time, initial concentration and temperature were evaluated. The adsorption behaviour suited well with Langmuir isotherm suggesting monolayer adsorption with a maximum adsorption capacity of 49.75 mg g−1 (BPA) and 67.56 mg g−1 (paracetamol). The kinetic studies established chemisorption and pore filling as preferred adsorption mechanisms. The adsorption was exothermic in nature and exhibited better performance at lower temperatures making it as suitable material for domestic water purification. The HBCN demonstrated robust stability and reusability ∼ 80 % (BPA) and ∼ 71 % (paracetamol) through 5 adsorption–desorption cycles. The working adsorption mechanism being followed were confirmed through FTIR and BET studies: pre and post adsorption with HBCN.