Comparative study of the adsorption of acetaminophen on activated carbons in simulated gastric fluid

Abstract

Samples of commercial activated carbons (AC) obtained from different sources: Norit E Supra USP, Norit B Test EUR, and ML (Baracoa, Cuba) were investigated. The adsorption of acetaminophen, Co = 2500 mg/L, occured in simulated gastric fluid (SGF) at pH 1.2 in contact with activated carbon for 4 h at 310 K in water bath with stirring. Residual acetaminophen was monitored by UV visible. The results were converted to scale adsorption isotherms using alternative models: Langmuir TI and TII, Freundlich, Dubinin-Radushkevich (DR) and Temkin. Linearized forms of the characteristic parameters were obtained in each case. The models that best fit the experimental data were Langmuir TI and Temkin with R2 ≥0.98. The regression best fits followed the sequence: Langmuir TI = Temkin > DR > LangmuirTII > Freundlich. The microporosity determined by adsorption of CO2 at 273 K with a single term DR regression presented R2 > 0.98. The adsorption of acetaminophen may occur in specific sites and also in the basal region. It was determined that the adsorption process of acetaminophen on AC in SGF is spontaneous (ΔG <0) and exothermic (−ΔHads.). Moreover, the area occupied by the acetaminophen molecule was calculated with a relative error from 7.8 to 50%.

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Design of Experiments Study on Scottish Wood Biochars and Process Parameter Influence on Final Biochar Characteristics

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Preparation of High Performance Activated Charcoal From Rice Straw for Cosmetic and Pharmaceutical Applications

“…The adsorption efficiency of RSAC samples on acetaminophen was measured by slightly modifying the method of Rey-Mafull et al (2014) [21] in simulated gastric fluid (SGF) at pH 1.2 and simulated intestinal fluid (SIF) pH 6.8. Briefly, acetaminophen was added to the SGF and SIF solutions reaching a concentration 200 µg/ml.…”