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In the present research ibuprofen (IBP) uptake, considered as a pharmaceutical and personal care product (PPCP), using synthesized copper-based metal-organic framework (MOF), HKUST-1, modified by dimethyl ethylenediamine (HKUST-1-mmen) was investigated. The structure of nano-composite and functional groups was characterized using SEM, EDX, FTIR, XRD, and BET analysis. Also, to optimize the experiments of IBP adsorption over HKUST-1-mmen, response surface methodology (RSM) was applied with three variables including pH, adsorbent dosage and contact time using central composite design (CCD). The optimum conditions for pH, adsorbent dosage and contact time were 3, 0.1 g and 83 min, respectively with IBP adsorption efficiency of 86.53%. The equilibrium data were compatible with Langmuir isotherm (qm = 1000 mg g−1) than other isotherm models, indicating the monolayer adsorption of IBP. According to the characteristics of IBP, HKUST-1, and the results of FTIR analysis, the adsorption of IBP on HKUST-1-mmen was through three possible mechanisms including H-bonding formation, interaction between unsaturated copper sites of HKUST-1 and -COOH from IBP and π–π stacking interactions. The kinetic studies also revealed that the Lagergren model was predominant and IBP was not chemisorbed on nano-composite surface. It was concluded from the thermodynamic parameters that the IBP adsorption was spontaneous, endothermic, and physical. [ABSTRACT FROM AUTHOR]

Cadmium as a highly toxic metal is released into the environment through paper production, metal processing, phosphate fertilizers, insecticides, and treatment of wastewater. Cadmium also inhibits the body activities and is very toxic for kidney and other organisms. In the current study, zinc-based metal–organic framework, zeolitic imidazolate framework (ZIF)-8, was synthesized and modified by dimethylethylenediamine (ZIF-8-mmen) for the removal of cadmium. To optimize the experiments, response surface methodology was applied with three variables including pH, adsorbent dosage, and contact time using central composite design. The optimum conditions for pH, dosage, and time were 2, 0.1 g, and 89 min, respectively, with removal efficiency of 85.38%. The Langmuir isotherm (qm = 1000 mg/g) indicates the monolayer adsorption. The kinetic studies reveal that the Lagergren model was predominant and cadmium was not chemisorbed. Thermodynamic parameters show spontaneous, endothermic, and physisorption processes. [ABSTRACT FROM AUTHOR]