Abstract:
This study evaluates a novel adsorbent for ciprofloxacin (CPX) removal from water using a composite
derived from municipal solid waste biochar (MSW-BC) and montmorillonite (MMT). The composite
adsorbent and pristine materials were characterized using powder X-Ray Diffraction (PXRD), Fourier-
Transform Infrared (FTIR) spectroscopy, and Scanning Electron Microscope (SEM) before and after the
adsorption. Batch experiments were conducted to study the mechanisms involved in the adsorption
process. Ciprofloxacin sorption mechanisms were interpreted in terms of its pH-dependency and the
distribution coefficients. The SEM images confirmed the successful binding of MMT onto the MSW-BC
through flaky structure along with a porous morphology. Encapsulation of MMT onto MSW-BC was
exhibited through changes in the basal spacing of MMT via PXRD analysis. Results from FTIR spectra
indicated the presence of functional groups for both pristine materials and the composite that were
involved in the adsorption reaction. The Hill isotherm model and pseudo-second-order and Elovich kinetic
models fitted the batch sorption data, which explained the surface heterogeneity of the composite
and cooperative adsorption mechanisms. Changes made to the MSW-BC through the introduction of MMT, enhanced the active sites on the composite adsorbent, thereby improving its interaction with
ionizable CPX molecules giving high sorption efficiency.
