Synergistic approach for synthesis of functionalized biochar for efficient adsorption of Lopinavir from polluted water

Abstract

The COVID-19 pandemic has led to a significant increase in antibiotic consumption, along with a 70% rise in antiviral drug concentrations in aquatic ecosystems. For the effective adsorption of antibiotics, biochar was modified by incorporating layered double hydroxide (LDH) through hydrothermal method. The results showed that LDH provides additional hydroxyl groups, positive surface charges and ion exchange. Whereas biochar component provides a larger specific surface area (467.8 m2/g). Batch adsorption experiments of biochar @ layered double hydroxide (BC@LDH) showed enhanced adsorption performance (832.9 mg/g), compared to pristine LDH (420.3 mg/g) and unmodified biochar (548.5 mg/g). Adsorption data were best interpreted (R2 = 0.99) by pseudo second order, Freundlich, and Temkin isotherm models. Adsorption was a synergism of LDH and biochar physiochemical properties, whereas pore-filling was the primary mechanism. The recyclability of BC@LDH confirmed its good structural stability. This study introduces a sustainable and efficient method for synthesizing a versatile adsorbent with superior antibiotic removal.