Abstract
BACKGROUND: Antibiotics are widely used for the treatment of bacterial infections in humans and animals, but it can be released into water sources due to incomplete metabolism in humans or via discharge from drug manufacturers.
RESULTS: The efficiency of removal of three antibiotics was enhanced with increasing biochar dosage. The adsorption of three antibiotics by RH700 was much higher than by RH300 and RH500, which might be due to the larger surface area and adsorption pore volume of RH700 (211.76 m(2) g(-1) and 6.25 nm, respectively). In addition, the adsorption capacity was greatly affected by the solution pH, background electrolyte and humic acid. The kinetics experiment data were well fitted by the pseudo-second-order kinetic model. The maximum adsorption capacities of tetracycline hydrochloride (TC), doxycycline hydrochloride (DC) and ciprofloxacin (CF) based on the Langmuir model by RH700 at 318 K were 80.9, 85.2 and 36.1 mg g(-1), respectively. RH700 exhibited high affinity for antibiotics, mainly ascribed to the chemical interaction between oxygen-containing functional groups (phenolic hydroxyl group, carboxyl and alkoxy groups) of the biochar surface and TC, DC and CF.
CONCLUSION: The rice husk biochar produced at high temperature could be applied as a potential adsorbent for removal of antibiotics from water. (C) 2017 Society of Chemical Industry.