Innovative biochar filters out pharmaceuticals from water

In a breakthrough for environmental remediation, researchers at the Universidad Nacional de Colombia have reported the successful use of biochar derived from corn cob for the adsorption of pharmaceutical pollutants. The study, published in the Journal of Bioresources and Bioproducts, focused on the removal of acetaminophen (ACE) and amoxicillin (AMX), two common pharmaceuticals found in water bodies that pose risks to both aquatic life and human health.

The researchers obtained biochar through ZnCl2 activation followed by carbonization at 700°C. The biochar's efficiency was tested through batch experiments, varying parameters such as contact time, temperature, pH, and initial concentration. The maximum adsorption capacity reached 332.08 mg/g for ACE and 175.86 mg/g for AMX. The adsorption kinetics and isotherm models were also determined, with the pseudo-second order and Langmuir model fitting ACE adsorption, and pseudo-first-order kinetics and the Freundlich isotherm model fitting AMX adsorption.

The study further explored the co-adsorption of ACE and AMX, revealing a synergistic effect on AMX but an antagonistic effect on ACE removal, with maximum capacities of 193.51 and 184.58 mg/g achieved, respectively. Fixed-bed column experiments demonstrated the dependence of adsorption capacity on influent concentration, with the breakthrough curve fitting both the Thomas and Yoon-Nelson models.

The adsorption mechanism was elucidated, highlighting surface interactions, such as hydrogen bonding formation and n-π interactions, as the main driving forces for the adsorption process. The study concluded that the biochar's high potential for pharmaceutical compound adsorption from water could pave the way for sustainable water treatment solutions.

See the article:

DOI

https://doi.org/10.1016/j.jobab.2023.10.003

Original Source URL

https://www.sciencedirect.com/science/article/pii/S2369969823000713

Journal

Journal of Bioresources and Bioproducts