Utilizing Hydrothermally Carbonized Food Waste-Derived Activated Hydrochar for the Elimination of Carbamazepine and Naproxen

Abstract

Abstract Chemical products (CPs), such as carbamazepine and naproxen, present in aquatic environments pose a considerable risk to both aquatic life and human health. This study aimed to explore the potential of employing hydrothermally carbonized food waste-derived hydrochar (AC-HTC-250) as an adsorbent to eliminate these CPs from water. The research specifically examined the influence of hydrothermal carbonization temperature on hydrochar properties and the ramifications of chemical activation using phosphoric acid on the hydrochar's adsorption capacity for carbamazepine and naproxen. Additionally, the activated and non-activated hydrochars' physiochemical and surface characteristics were scrutinized in depth. The investigation demonstrated that the hydrothermal carbonization process contributed to an increase in hydrochar surface area from 1.47 to 7.52 m2/g, which was subsequently amplified to 32.81 m2/g through phosphoric acid activation. Batch adsorption experiments indicated that AC-HTC-250 hydrochar exhibited high efficiency in removing carbamazepine and naproxen, with adsorption capacities of 49.09 mg/kg and 14.34 mg/kg, respectively. The study also revealed that the adsorption data corresponded well with the Langmuir model and pseudo first-order models. The solution's pH exerted a strong influence on carbamazepine and naproxen adsorption, with the optimal pH for both compounds determined to be 4. These findings hold potential for applying hydrothermally carbonized and chemically activated food waste-derived hydrochar as an adsorbent in wastewater treatment processes.