Active Pharmaceutical Ingredients Sequestrated from Water Using Novel Mesoporous Activated Carbon Optimally Prepared from Cassava Peels

Abstract

The increasing occurrence of active pharmaceutical ingredients (APIs) in water systems coupled with their recalcitrance to conventional water treatment methods calls for research into more eco-friendly and cost-effective curbing media. Mesoporous cassava peel activated carbon (CPAC) was prepared under conditions derived from optimizing the surface area and yield with the temperature and holding time as the model inputs using the response surface methodology. The sequestration potential and mechanisms of the resultant activated carbon (AC) for active pharmaceutical ingredients from wastewater were studied using batch experiments. The CPAC adsorption kinetics and isothermal mechanisms for the three pharmaceuticals (carbamazepine (CBZ), clarithromycin (CLN), and trimethoprim (TRM)) were studied in both wastewater and Milli-Q water. The API concentrations were measured using liquid chromatography coupled to a mass spectrometer (LC-MS) system. The maximum removal efficiencies were 86.00, 58.00, and 68.50% for CBZ, CLN, and TRM for wastewater, which were less than those from the Milli-Q water at 94.25, 73.50, and 84.5%, respectively. The sorption process for the CLN was better explained by the Freundlich model, whereas the CBZ and TRM adsorption processes could suitably be explained by both the Langmuir and Freundlich models. At an initial concentration of 20 mgL−1 for all APIs and a CPAC dosage of 2.0 gL−1, the maximum adsorption capacities were 25.907, 84.034, and 1.487 mgg−1 for CBZ, TRM, and CLN, respectively. These results demonstrated the potential of CPAC to remove APIs from water, with its sequestration potential being more exhibited after the removal of the organic matter owing to the lower competition for active sites by the APIs. Additionally, positive adsorbates were better removed than negatively charged adsorbates due to the dominance of anions in the cassava peel lattice.

Simultaneous removal of chloride and hardness from groundwater by cassava peel biosorption: Optimization and sorption studies

“…The data indicate T A B L E 2 -, bicarbonate; K + , potassium; Mg 2+ , magnesium; SO 4 2-, sulfate; TA, total alkalinity; TB, turbidity; TH, total hardness; WHO, World Health Organization.T A B L E 3T A B L E 4 − across most of the experimental runs. This differential affinity can be attributed to the chemical composition of CP, which contains an abundance of hydroxyl and carboxyl functional groups, as reported in the literature(Kayiwa et al, 2022). At neutral pH conditions, these groups ionize to form negatively charged hydroxylate and carboxylate anions, which act as active binding sites.…”

“…During the first 25 min, both Cl − and TH were rapidly absorbed, reaching 74% and 85%, respectively. This could be ascribed to the abundance of active sites on the CP surface, which allowed for higher and faster Cl − and TH absorption (Kayiwa et al, 2022; Zeng et al, 2020). However, the removal remained consistent between 30 and 40 min, indicating that the particles were entering deep inside the pores of the adsorbent while the binding sites were steadily saturated (Huang et al, 2021; Ji et al, 2020; Luo et al, 2021).…”

Comparison of Modified Peels: Natural Peels or Peels-Based Activated Carbons for the Removal of Several Pollutants Found in Wastewaters

“…Many studies have investigated the development of lowcost adsorbents from agricultural wastes in order to eliminate heavy metals, fluoride ions, pharmaceutical residues, and dyes. Various types of peels, including banana, pomegranate, orange, cassava, shaddock, potato, etc., have been employed as natural sources for the production of activated carbon [37][38][39][40]. They are a low-cost option for bio-materials that are, additionally, ecologically friendly.…”