Removal of ciprofloxacin via enhancing hydrophilicity of membranes using biochar

Abstract

Growing concerns regarding the presence of pharmaceuticals in wastewater necessitate their removal. Membrane filtration offers a promising approach. This study explores the development of biochar incorporated mixed matrix membranes (MMMs) for ciprofloxacin removal from water. Biochar, derived from the pyrolysis of agricultural waste, was blended with polyether sulfone (PES) and polyvinylpyrrolidone in varying ratios. The resulting MMMs exhibited progressively improved properties with increasing biochar content. Notably, membrane M₁₁, comprising equal parts PES and biochar, displayed the highest porosity, lowest surface roughness (12.0), and lowest contact angle (31.05°), indicating enhanced hydrophilicity (increased by 58.19% compared to the biochar-free membrane). M₁₁ effectively removed ciprofloxacin along with three additional antibiotics from different classes. Fourier-transform infrared spectroscopy and X-ray photoelectron spectroscopy analyses corroborated the removal of ciprofloxacin. Furthermore, M₁₁ demonstrated excellent regenerability, retaining over 57% removal efficiency after four cycles. These findings highlight the potential of M₁₁ as a sustainable and cost-effective membrane for pharmaceutical removal from wastewater.