Iranian Journal of

Background and Objective: Extreme use of antibiotics and discharging to the environment lead to serious consequences. Mesoporous silica such as MCM-41 material is widely used to absorb contaminants from the aqueous solution. The aim of this study was to evaluate mesoporous synthesis of MCM-41 and its efficacy for removal of the antibiotic cephalexin from aqueous solution.
Materials and Methods: Physical characteristics and absorbent structure synthesized by techniques BET, FTIR and XRD were analyzed. The effect of variables such as pH values (3, 7, 11), the dose of MCM-41 (200, 500, 800 mg/L), initial concentration of cephalexin (50, 75, 100 mg/L), contact time (30, 60, 90 min), and process temperature (20, 30, 40 ⁰C) on absorption of cephalexin were studied. In order to achieve the optimal experimental conditions, response surface methodology (RSM) model was used.
Results: The results showed that pH (p=0.0001), adsorbent dose (p=0.0001), initial concentration of cephalexin (p=0.0001), contact time (p=0.01), pH² (p=0.0002) and pH (p=0.04) and initial concentration had a significant impact on the response variable. The optimum removal condition based on analysis of variance and the model was at the reaction time 90 min, pH 3, initial concentration 50 mg/L and adsorption dose 600 mg/L. Under these conditions, the removal efficiency of 81.1% was achieved.
Conclusion: The results showed that adsorption process with the mesoporous MCM-41 had a high efficiency on the removal of cephalexin from the aqueous environments.
 

Background and Objective: Due to the presence of industrial pollutants in water sources, it is necessary to treat wastewater, especially colored wastewater. This study aims to treat wastewater containing methyl orange dye using nano mesopore SBA-16.
Materials and Methods: In this study, the effect of different parameters (pH, concentration of methyl orange, amount of adsorbent, temperature, and contact time) on the absorption of methyl orange by nanocomposite prepared with the help of Design of Experiment 7 software and Response Surface Method (RSM) was investigated.
Results: The maximum amount of pollutant removal by the adsorbent was obtained under optimal conditions of pH = 4.07, temperature 50 °C, contact time 35 minutes, initial concentration of adsorbent 10 mg/L, and amount of adsorbent 0.04 g. Also, the findings showed that the absorption behavior is most consistent with the Langmuir isotherm and the absorption process is exothermic and spontaneous at low temperatures.
Conclusion: In optimal conditions, the SBA-16 adsorbent was able to remove 98.60 % of methyl orange from the aqueous solution and the maximum adsorption capacity (qmax) for the removal of methyl orange pollutant was 37.73 mg/g. Considering the high potential of nano mesopore SBA-16 in removing methyl orange pigment, it can be considered a suitable candidate for removing colored pollutants and treating wastewater from textile factories.