Adsorption analysis of ciprofloxacin and delafloxacin onto the corn cob derived-biochar under different pyrolysis conditions

This study exhibited corn cob biochar (CCBC) as an effective adsorbent with the capability to reduce water-related contamination generated by potent antibiotics such as the new generation of fluoroquinolones (FQs). However, it has been hypothesized that the FQ’s adsorption capability is strongly influenced by the pyrolysis temperature at which the CCBC is formed. Different pyrolysis temperatures (600 °C, 700 °C, 900 °C) and residence times (1 h and 2 h) were examined to characterize the CCBC’s adsorption property. For the first time, Bayesian non-linear regression based on the Langmuir adsorption model was applied to accurately estimate the adsorption capacity of the FQs ciprofloxacin (CFX) and delafloxacin (DFX). The results showed that the biochar produced at 900 °C in 2 h of pyrolysis had the best iodine adsorption capacity, with the estimated maximum surface area CCBC of 2918 m 2 g −1 . The CFX and DFX adsorption capacity were similarly at their highest with biochar generated at 900 °C and 2 h of pyrolysis. However, the adsorption of CFX was greater than DFX and this was estimated by the micropore structure of CCBC. Infrared spectra (FTIR) detected the carboxyl group and ester group which could be explained by the high value of K L in the Langmuir model. The results have shown the capability of the Corn cob biochar in removing FQs from the environment and it is a cost-effective material that can be developed for other emerging contaminants as well.