An efficient adsorbent: Simultaneous activated and magnetic ZnO doped biochar derived from camphor leaves for ciprofloxacin adsorption

In this work, a novel magnetic biochar of camphor leaf with large micropore area was prepared for ciprofloxacin removal. Biochar show the advantage of resource utilization, as an adsorbent in pollutant removal, but limited by its relatively low specific surface area and poor adsorption capacity. An efficient method was formulated to prepare ZnO nanoparticle modified magnetic biochar to adsorb ciprofloxacin. The biochar with ZnCl₂/biochar mass ratio of 2 at the calcination temperature of 650 °C was a typical microporous material with huge surface area (915 m² g^-1). The maximum ciprofloxacin adsorption capacity of the biochar reached 449.40 mg L^-1. The adsorption mechanism was discussed in terms of physical adsorption and chemisorption involving intense π-π stacking interaction, electrostatic interaction, cation exchange interaction etc. The adsorption capacity of biochar did not decline adsorption capacity significantly after 3 times regeneration. It provides a recycle and reuse way for camphor leaves resource disposal.