The average particle size of ASNWs were 172–238 nm ( Perumal et al. Prepared ASNWs were taken in Petri dishes, dried in hot air oven at 80 ☌ and stored in closed containers. The obtained reaction mixture was washed five times with ethanol and centrifuged at 5,000 rpm for 15 min. For the synthesis of ASNWs, 0.4 ml of HDTMOS was added and 12 h of reaction time was provided for hydrolysis of HDTMOS. The mixture was undisturbed overnight at ambient temperature for the hydrolysis of TEOS. 2 ml of TEOS was added to introduce the hydrophilic character to the prepared surfactants. To this solution, 5 ml of deionized water, 1 ml of 0.18M of the sodium citrate aqueous solution, 1.15 ml of ammonium hydroxide solution and 30 ml of ethanol were added, and immediate gentle shaking was provided to the mixture for 30 sec to keep all the components well mixed. 15 g of PVP was dissolved in 150 ml 1-pentanol and sonicated for 35 min. The ASNWs were prepared by wet chemical process. The contribution level of each of these process parameters and its significance have been analysed using analysis of variance (ANOVA) ( Reyhani & Meighani 2015). S/N ratios have been calculated for the batch process optimization by using three methods, namely – nominal-the-better, smaller-the-better and larger-the-better ( Shahavi et al. S/N ratios have been used to analyse the contribution of each and every experimental factor. This method reduces the experimental cost and enhances the reliability of the results. Taguchi suggested that the orthogonal arrays for controlling the parameters should be applied in order to determine the level of factors for the experimental design ( Nagpal et al. ![]() Genichi Taguchi developed the Taguchi experimental design method to evaluate the effect of the process parameters and to determine the optimal process conditions in order to achieve the maximum efficiency with minimal experimental runs ( Hsu et al. So, a comprehensive and detailed study on PELM preparation and its application for extraction of Cu (II) and Cd (II) from aqueous solution has been carried out and, additionally, an experimental design for multivariable optimization by Taguchi design had also been investigated. Until now, to the best of our knowledge, the removal of Cu (II) and Cd (II) from aqueous solution by the PELM technique has not been reported by the research community. Pickering Emulsion Liquid Membrane (PELM) stabilized by the solid particles has received great attention in areas like wastewater treatment, food science, drug delivery, biphasic catalysis, and in the preparation of porous materials ( Xie et al. The emulsions formulated using micro and nano-sized solid particles as stabilizers are called Pickering emulsions ( Hedjazi & Razavi 2018). The pioneering work of Ramsden, which resulted in Pickering emulsion, has opened a new window to emulsion science, and it is now renowned that the solid colloid particles would be the best alternative for conventional emulsion stabilizers. The surfactants are repeatedly adsorbed and desorbed at the interface of the ELM, which leads to phase separation ( Zeng et al. The ELM is a double emulsion type membrane with either water in oil in water (w/o/w) emulsion, or oil in water in oil (o/w/o) emulsion. ![]() The ELM system consists of three phases: (i) wastewater as in the feed phase, (ii) a diluent along with an extractant and a surfactant as in the membrane phase and (iii) NaOH, as in the stripping phase. The Emulsion liquid membrane (ELM) is an effective technique for the recovery of the various toxic organic and inorganic compounds from wastewater when compared to the conventional methods like liquid – liquid extraction, solid – liquid extraction, and so on. The higher values of F and lower values of P (less than 0.05) indicate pH is the most significant parameter on the percentage extraction of Cu (II) and Cd (II) using the Taguchi design approach. The impact of each process factor on the extraction efficiency of Cu (II) and Cd (II) ions has been verified using analysis of variance (ANOVA). Non-edible oils were used as diluent in this present study to reduce the need for toxic organic solvents in preparing PELM. At optimum conditions, the extraction efficiency of 89.77% and 91.19% for Cu (II) and Cd (II) ions were achieved. The influence of the process parameters such as pH, the stripping phase concentration, the agitation speed, and the carrier concentration on the extraction efficiency have been examined to find the optimum conditions at which the maximum recovery of Cu (II) and Cd (II) could take place. In the present study, the extraction of divalent heavy metals like copper and cadmium using a Pickering Emulsion Liquid Membrane (PELM) has been investigated by using three different surfactants such as Amphiphilic silica nanowires (ASNWs), Aluminum oxide nanoparticles (Alumina) and Sorbitan monooleate (SPAN 80).
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |