Evaluating the Removal of the Antibiotic Cephalexin from Aqueous Solutions Using an Adsorbent Obtained from Palm Oil Fiber

Abstract

This study aimed to understand the adsorption process of cephalexin (CPX) from aqueous solution by a biochar produced from the fiber residue of palm oil. Scanning electron microscopy, Fourier transform infrared spectroscopy, Boehm titration, and the point of zero charge were used to characterize the morphology and surface functional groups of the adsorbent. Batch tests were carried out to evaluate the effects of the solution pH, temperature, and antibiotic structure. The adsorption behavior followed the Langmuir model and pseudo-second-order model with a maximum CPX adsorption capacity of 57.47 mg g−1. Tests on the thermodynamic behavior suggested that chemisorption occurs with an activation energy of 91.6 kJ mol−1 through a spontaneous endothermic process. Electrostatic interactions and hydrogen bonding represent the most likely adsorption mechanisms, although π–π interactions also appear to contribute. Finally, the CPX removal efficiency of the adsorbent was evaluated for synthetic matrices of municipal wastewater and urine. Promising results were obtained, indicating that this adsorbent can potentially be applied to purifying wastewater that contains trace antibiotics.

Cephalexin Adsorption by Acidic Pretreated Jackfruit Adsorbent: A Deep Learning Prediction Model Study

“…The adsorbent between 5 and 10 mg/100 mL and pH between 4 and 8 having a synergistic effect on the adsorption of CFX, where the removal could reach more than 90%. These findings are consistent with previous studies which mentioned the pH influences related to the effect on the adsorbent surface charge and functional groups: the CPX removal was 90% at pH 6.5, however, the removal efficiency decreases as the pH value reaches 12 [26]. Based on the simulation for the effect of time and dose on the CFX removal, it was noted that the maximum removal lies in the range of 20 to 40 min and with 5 to 10 mg dose/100 mL.…”

“…At high concentrations of APJAP dosage (10 mg/100 mL) the removal was 44.52 vs. 33.18% for the actual and predicted results, respectively, perhaps due to the agglomeration of the adsorbent. Acelas et al [26] revealed that the maximum removal of CFX (>90%) was recorded at pH 6.5, 2 g/L of the adsorbent dose (palm oil fiber). Rashtbari et al (2018) reported that the time required to achieve high CFX removal efficiency depends on CFX concentration.…”

Adsorption of Zn2+ from Synthetic Wastewater Using Dried Watermelon Rind (D-WMR): An Overview of Nonlinear and Linear Regression and Error Analysis

“…These findings also demonstrated that Zn 2+ adsorption was controlled by an ion-exchange process [70]. In addition, the ∆S • for removing Zn 2+ was determined to be 13.328 and 24.041 kJ/mol * K. Consequently, the positive ∆S • values confirmed the increased randomness at the solid-solution interface during the removal process [71,72]. The release of H+ ions from the adsorbent surface might explain the positive entropy changes (∆S • ) for Zn 2+ adsorption [58].…”

Application of Saccharomyces cerevisiae/Calcium Alginate Composite Beads for Cephalexin Antibiotic Biosorption from Aqueous Solutions

“…For the first mentioned isotherm model, the maximum adsorption capacity of CPX on Saccharomyces cerevisiae/calcium alginate beads was of 94.34 mg/g, significantly lower than that calculated by Bangari et al [35], who conducted absorption of CPX on boron nitride nanosheets, but higher than that indicated by Acelas et al [57], who used palm oil fiber as a precursor for an adsorbent material able to remove CPX from aqueous solutions.…”