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[Display omitted] • Ciprofloxacin (CIP) adsorption from fresh synthetic urine was studied; • A double layer with one energy model described well the equilibrium data; • GO showed high adsorption capacity in different media (≥291.39 mg g−1); • Experiments using CIP concentrations commonly found in urine were performed. This work uses conventional and statistical physics modeling approaches to address ciprofloxacin (CIP) adsorption by graphene oxide (GO) from aqueous solution and fresh synthetic urine. Instrumental techniques such as FTIR, XRD, SEM, TGA, BET, and EDS were employed to characterize the adsorbent material. The adsorption experiments were performed in a typical batch using different initial concentrations of CIP, adsorbent dosage, pH, and temperatures. Besides, the statistical physics approach was employed to investigate the CIP adsorption onto GO. Five models based on mono, double, and multilayers were used to describe the equilibrium isotherms. Steric and energetic parameters such as the number of adsorbed molecules per site, receptor site density, and half-saturation were considered. The kinetic data were adjusted using three conventional models (pseudo 1st order, pseudo 2nd order, and general order). The pH effect and influence of adsorbent dosage on adsorption performance were also investigated and discussed. In addition, adsorption mechanisms hypotheses were proposed based on experimental data and adsorption modeling using a statistical physics approach. Furthermore, the current work reports the removal of CIP at concentrations commonly found in urine considering factors such as fraction excreted in unmetabolized form, daily defined dose, and average daily urine volume excreted. The adsorption capacity values in aqueous medium and fresh synthetic urine were were 354.24 and 291.39 mg g−1, respectively. [ABSTRACT FROM AUTHOR]

[Display omitted] • New statistical physical insights of the water sorption isotherms on lemon leaves; • A finite multilayer model represented the isotherms at 40, 50, and 60 °C; • The experimental sorption isotherms obtained for lemon leaves are Type II; • Sorption energies are less than 50 kJ mol−1. A deeper analysis of the water sorption isotherms on lemon leaves (40, 50, and 60 °C) was carried out using statistical physical modeling to obtain information about the sorption mechanism and better understand the process. For this, a theoretical model was developed based on the grand canonical potential to describe the experimental data, and the isotherms were analyzed using the finite multilayer sorption model. The experimental sorption isotherms obtained for lemon leaves are Type II. The model used to analyze the process showed excellent predictive capacity, with coefficient of determination values above 0.97 and root mean square error below 0.08. The interpretation of the estimated parameters indicated that the water molecules are parallel to the surface of the lemon leaves, which allows the formation of finite layers of water. The system is directly affected by temperature, where increasing temperature decreases the density of receptor sites. The process occurs through physisorption since the calculated sorption energies are less than 50 kJ mol−1. The thermodynamic analysis of the process shows that water sorption on leaves is exothermic and spontaneous. This work contributes to a better understanding the drying process through the results obtained. [ABSTRACT FROM AUTHOR]