چكيده به لاتين
The presence of drugs in the environment is one of the significant issues in today's world. Most of the drugs consumed by humans and animals are excreted unchanged or in a metabolized form through urine and feces. Therefore, finding a suitable method to remove these pollutants is very important. Although the emulsion liquid membrane method has been highlighted due to its simplicity, high selectivity, fast extraction and low energy consumption, its commercialization operation has been limited due to the instability of the emulsion and the problem of emulsion breakage after the extraction process. The Pickering Emulsion stabilized by special nanoparticles, such as carbon nanotubes, due to their longer stability, cost-effectivity, and less toxicity has been developing as a matter of great interest for researchers. In this study, the extraction of the Ibuprofen drug as a kind of pollutant at the simultaneous presence of the nanoparticle and surfactant has been investigated. In the Pickering Emulsion Liquid Membrane process used in this study, the multi-walled carbon nanotube, Span 85, Aliquat 336, Kerosene, and Sodium chloride solution were used as the nanoparticle, surfactant, carrier, solvent, and internal phase. Using the response surface methodology in Design-Expert software and based on the central composite design, the optimization of the concentrations of multi-walled carbon nanotube, Span 85, feed, and Aliquat 336 and the mixing time, stirring speed, homogenizer speed, emulsification time and internal phase to membrane phase ratio were performed. The significant and non-significant of these six parameters and their interactions with each other have been evaluated. A second-order regression model was obtained for measuring the extraction efficiency of Ibuprofen. The one-dimensional and three-dimensional diagrams were developed for investigating the effect of different variables on extraction efficiency. The maximum extraction efficiency of Ibuprofen obtained by the response surface method at first set was 93.63%, which was achieved at the concentrations of 0.071 %wt/v, 5.06 v/v%, 73.54 ppm, and 1.68 v/v% for the multi-walled carbon nanotube, Span 85, feed, and carrier, respectively, mixing time of 6.42 min, and stirring speed of 246 rpm. In the second set in optimal conditions; 12145 rpm, homogenizer speed, 8.34 minutes of emulsification time and internal phase to membrane phase ratio 0.96, the highest percentage of optimal value equal to 95.20% was obtained. Among the innovative aspects of this research, can be mentioned the simultaneous use of Span 85 and multi-walled carbon nanotube as a surfactant in membrane liquid along with Aliquat336 as the carrier in order to improve the stability and extraction performance of emulsion liquid membrane.
