The new cationic surfactant, Hy-1622 and characterized in the solid-state by FT-IR, and in solution by1H-and13C-NMR spectroscopy. The value of (CMC) or critical micelle concentration was determined by UV-visible spectroscopy. Interaction of surfactant with cerium ion was studied by UV-visible spectroscopy. These surfactants were proved to be efficient in increasing the solubility of cerium molecules. To test the carrier efficiency of cationic surfactant against cerium-bond coordinate, a new complex interaction of recently reported cerium complex was tested with synthesized cationic surfactants by conductometric measurements 22. The aim of FTIR- that there are no cation–cationic surfactant interactions in the aqueous solution of the mixed surfactants cationic and nonionic components of the cation. According to this experimentally, we contract that the surfactant Hy-1622 does not form a complex with the cerium complex and that the reduction of the free surfactant cation concentration in the solution causes a reduction of the leveling labor of the surfactant in the system involving the same charged cerium ion and cationic surfactant. The importance of vibrational frequencies of the Hy-1622 with a molecule in the C–H stretching region is shown in Figure 3. shows the FT-IR spectra before and after adding 2-DEHEHP measured for the representative sample containing 65 wt% of (Ce(NO3)2OH.3H2O. 2-DEHEHP) particles in emulsion and 35 wt% of Hy-1622 cationic surfactant together with pure Hy-1622 reference. The spectra of the control sample consist of characteristic peaks ascribed to the following vibrations at around 4000-500 cm^-1 to the (CH3-CH3) frequencies are observed in 3813.78, and 3500.49 cm⁻¹, respectively222324. The CH3 feature located in a frequency lower than 3548.43 cm⁻¹ is indicative of the crystalline structure. The CH3 asymmetric stretching mode presents a value 10-12 cm⁻¹ smaller than that observed for the molecules. {(CeO2.. 2-DEHEHP)}. Furthermore, the -CH3- mode is only 2 cm⁻¹ lower than that found in the molecules in the emulsion, in agreement. It is necessary to assign these bands. The CH_3-CH₃ bands of the [Ce(NO₃)₂ OH.3H₂O. 2-DEHEHP] molecules are difficult to be observed in (b) due to their lower intensities [25,26]. It is only possible to detect them with packing densities larger molecules. It is important to indicate that it is also difficult to distinguish between CH₃- and -N–CH₃- bands, observing only a large band with low intensity in the region between 2952.62 and 3034.27 cm⁻¹. O-H stretching, 2351.33-2094.63 cm^-1 to the C-H stretching, 1768.30 cm^-1 to the N–O bands stretching vibrations in nitroalkanes occur near 1609.34-1509.04 cm^-1 carbonyl stretching vibration, 1469.16 cm^-1 the C-H bending, 1288.12 cm^-1 the C-O-C symmetrical stretching, 921.63 and 832.97 cm^-1 the C-H bending kidding as well as 712.06 cm^-1 ascribed to the buckle vibrations of Hy-1622 chains, respectively. IR spectra of the Hy-1622 in (Ce(NO₃)₂OH.3H₂O. 2-DEHEHP) hybrid material is essentially the same with one exception in the appearance of an extra band at 562.24 cm^-1 272829. This peak is associated with the vibrations of the Ce-O bonds corresponding to intrinsic stretching vibrations of the metal cation Ce(NO₃) OH.3H₂O at tetrahedral in nitrate medium. This fact gives straightforward evidence of proper incorporation of the cerium nitrate particles into the Hy-1622 with emulsion.

The cerium ion is transported from the aqueous phase or feed into the receiving phase via the oil membrane. The movement of charge cerium ion species through the DEHEHP, B (15%v/v) as the hydrophobic liquid membrane is achieved, by the presence of a cooperative factor collected by DEHEHP, B. After complexation of the carrier with Ce(IV) on the source outline phase of the membrane, the DEHEHP, B-Ce(IV) distribute, down its concentration gradient. On the receiving phase of the membrane, the metal ions species would be released into the receiving phase across the formation of a ternary complex from carrier/Ce (IV)/sodium nitrate). At this phase, the free carrier diffuses back via the liquid membrane. The data is the transport of cerium ion from the aqueous phase into the aqueous receiving phase via the bulk of the oil membrane phase 303132, described a schematic diagram of this mechanism is shown in equations (2&3).

…1at pH <1.8….(2)

…2 at pH >2.5…(3)

Where HR that the Di-(2-ethylhexyl) phosphoric acid extractant and the aq. and org. denotes aqueous and organic phase conditions respectively. At pH>2.0 the precipitate formation of Ce(OH)₂ tends to diminished the efficiency, Ce(IV) aqueous concentration decreasing the Cerium extraction.

Role of diversified constituents of organic phase during the liquid surfactant membrane formulation Feed phase at pH =2.5 has a very strong effect on the concentration of acidic dissociated (H⁺ + A⁻) as (2-ethylhexyl) phosphoric acid in ^H+,[NO₃]^-2.In a typical experiment, 15 ml of the required metal ion (5.0 ×10^-4 M) was placed in the titration cell, thermostated at 25⁰C, and the conductance of the solution was measured. Then, a known amount of a concentrated DEHEHP, B solution (1×10^-3M) using a calibrated micropipette. The conductance of the solution was measured after each addition. The ligand solution (L) was added continually until the required (L: M) ratio was achieved. The formation constants, K_f, and the molar conductance (ɅM), of the resulting 1:1 complexes between 2DEHEHP, B and the Ce (IV) cation used, in different mixtures and at different from 10-25⁰C, were calculated by fitting the observed molar conductance, Λ_obs, at varying ^{DEHEHP B}/[Ce⁴⁺] mole ratios to express the Λ_obs as a function of the free and complexes Ce(IV) ions. Figure 4 A nonlinear least-squares curve fitting using the computer software program was applied to appreciate formation, stability, and determining that molar conductance of the resulting are equally complexes 31. In the present work, all of the measured solutions were adjusted in pH range 1–2.5 using a pH-meter of the type B-417 HANNA instrument, and the prevailing cerium species were in the form of Ce(NO₃)₃. Figure 5. The value indicates that DEHEHP, B is an appropriate extractant to work as a phase transport catalyst to separate Ce(IV) cation and another cations transport (water/Oil/water) through DEHEHP,B in the bulk liquid membrane system.

This may be due to the size of the Ce⁴⁺(r = 1.05 A˚) ion and, therefore, it can connect a fit condition for the DEHEHP, B (r=2.8A˚) cavity. Another data, we preliminarily investigated on competitive transmission, of cerium ion among some various metal cations and affected of surfactants also. Table 3. Study the effect of type surfactants on interfering ions source phase (5 ml) at pH=2.5. It was found that DEHEHP, B has the required ability to transport Ce(IV) cation against its concentration gradient through the bulk liquid membrane.

The optimal conditions parameter indicate a stable emulsion is emulsification speed: 2000-4000 rpm,

emulsification time at 3 min, agitation speed: 300 rpm, internal phase concentration (NaNO₃):1x10^-3M carrier concentration (DEHEHP, B): 22% (w/w), Hy-1622 surfactant concentration and 3% Span 80/85 (w/w), volume, the ratio between the membrane phase and internal phase 1:3 and the volume ratio between the emulsion phase and the external phase as 1:1, 1, 2-dichloroethane as diluent. The chemical structure of the Hy-1622 surfactants was confirmed using FT-IR spectra characterization and biological activity of colloidal cerium. Besides, the cationic surfactant showed a high recurrence estimated in a period of comparative is to transport the ultimate amount of waste during the treatment process. The calculated diagram of prevalence, on a species of Ce(IV) enhances, these observations in Figure 6. The hydrolyzed species of cerium cation are probable at most coexist at pH < 3. Where aqueous, species are not the only ones affected by pH. At higher pH, the cerium hydroxide compound 3334 prevalent and may subsequently precipitate spontaneously without any current depending on the degree of H⁺ ion of an aqueous solution. This compound has been present already. The extraction of Ce(IV) higher when the feed phase concentration is in the range of HNO₃ up to 7M as in Figure 7. This is prospective, because the formation of the complex between cerium ion species and extractant is most preferable, at (1-7 M) acid concentration. When the reaction rate becomes high, the driving force for mass transfer of the (DEHEHP, B-Ce(IV)) complex through the water-oil proceeds increases, and the metal complex moves on to the oil phase. Finally, the rate of the ^{DEHEHP B} complex formation depends directly on the H⁺ion concentration in the external phase depending on agitation speed at 300 rpm, therefore increasing the agitation speed value for the extraction phase, and the removal efficiency will be increased 35. The same removal efficiency for the studied concentration range of Ce(IV) is due to the stable amount of carrier in the experiments. The cerium ion complex should be diffused through the membrane phase to the more inner area of the globule to cast cerium ion in the internal phase.

(Figure 6) shows the possibility of studying the role of ionic dissociation on the effect of surfactants in the emulsion carrier. Assuming that, in each range of Hy-1622 concentration, the cation surfactant and substrate can relate together and an equilibrium relation exists. The Hy-1622 concentration in which the equilibrium relation between the added cationic surfactant and the ions species existing in the solution, study the equilibrium between cationic-nonionic surfactants and complex produced from equilibrium surfactants and equilibrium equations (4,5). Cerium ion species in previously Figure 6 represent Ce(OH)₄ or Ce_species in equilibrium step 1 and 2(e_1,2) and S _(A,C) anionic and cationic surfactants.

…….(5)

Experiments were performed under the optimal conditions as mentioned previously with a carrier concentration. In a benzethonium chloride as an LSM system, a surfactant added as an emulsifier in the liquid membrane phase affects not only the stability of the liquid membrane but affect the swelling of the emulsion and the rate of cerium ion extraction. Initiatory experiments were proceeding, using benzethonium chloride (Hy-1622) and Span, 80/85 (3:1) as a cationic surfactant. Data indicated that Hy-1622 gives higher breakage values while Span 80/85 due to lower break-up of the emulsion. Thus Span 80/85(3:1) was chosen as a nonionic surfactant in this study 36. Figure 8 Explains the effect of various surfactant concentrations on emulsion stability. Although the emulsion was predictable to be stabilized with increasing surfactant concentration as a function on the degree of stability becomes approximately fixed led to the saturation of nonionic and cationic surfactants at the O/W interface. It is known that the increase in the concentration of surfactant does not countenance extraction kinetics 33. The amount of surfactant in the membrane must be lower, but it must be sufficient to stabilize the emulsion.

The volume fraction of the stripping phase and the viscosity of the oily phase determine the viscosity of the W/O emulsion. The viscosity of the oily phase is proportional to the stability of emulsions. Subsequently, utilizing highly viscous oil as a membrane phase can supply more stable emulsions. However, it has been found that the increased viscosity of the membrane safely decreases the diffusivity for anisotropic fluids. Thus, this medication reduces a solute diffusivity, and consecutive lowering in the extraction rate has been specified, as a movable, in the ELM process.

Interfacial tensions in separate ions by using cationic/anionic surfactant mixtures in one aqueous phase-, without and with NaNO₃ added were determined by the spinning drop method at 25^oc. The relation between interfacial tension and the concentration cationic/anionic surfactant mixtures determined by the density and viscosity is shown in Table 4.

The treat ratio, defined as the volume ratio of the emulsion phase (V_m) to the aqueous external solution (V_Ce), an important key in determining the efficiency of ELM. Through experiments were to study the effect of treat ratio on the extraction of cerium ion species. It's not changeable random, because it is necessary to pledge that the HNO₃ concentration that's existent in the internal phase is high enough to react with the external phase which is the cerium nitrate solution. The flow rate ratio of the dispersed phase to the continuous phase was varied from (V_m: V_Ce =1:2) to (V_m:V_Ce = 1:50) by confirmation, the flow rate of the dispersed phase as 25 ml/min and changing the flow rate of the continuous phase, which is the external phase, from 25 to 100 ml/min. The influence of the treat ratio of V_m into V_Ce(IV) is shown in Figure 9. It is found that at a treat ratio of (1:2), the achievement, recovery of solute in the external phase is high, and an increase in treat ratio reduces the removal efficiency. It is apparent that the volume ratio between the feed into emulsion solution decrease due to the removal efficiency also decreases. Additionally, the effect of (V_em) the volume ratio of emulsion to the external feed (V_feed) solution on the stability is found to be derivative, because the breakage increases very slightly with an increase of this volume ratio. Also, the increase in the treat ratio with a reduced external volume phase, the volume of emulsion will be increased. Thence, increasing the surface area for mass transfer due to the formation of a larger number of emulsion globules. In this work that emulsion type is dependent on the relative phase volume concluded that at a phase volume to the emulsion would be congested, more densely than was possible. This means that any attempt to exceed a phase volume of ɛ= 1.07 for the internal phase has to be data in each, inversion, or breaking. Figure 10 declares the effect of the volume ratio of oil to water O/W on emulsion stability at the Hy-1622 dosage of 1:2. When the ratio of O/W was decreased gradually, from 1:10 to 1:1, the comparative volume of the emulsion was increased consistently. As shown in Figure 11 after 18 h, the comparative volume of the emulsion was 16.27% in the ratio of 1:10. The relative volume of the emulsion was 27%, 47%, and 85%, at 12 h,18hr, and 20 h, respectively 373839. When the ratio was 1:1 at ½ h, the relative volume was 97.3%. At this ratio, the relative volume was ultimately constant throughout 20 h, indicating that the emulsion the best stability.

To prepare emulsions of two liquids that are insoluble or dominate only slight reciprocal, solubility. Benzethonium chloride as emulsification is usually accomplished, by the application of mechanical energy. At first, the interface between the two liquid phases is distorted to such a dimension, that large droplets are established, and these large droplets are posteriorly separate, into a minimum. During emulsification, the interfacial area between two aqueous solutions increases. Liquids lead to minimizing this surface area; thus, the driving force is required for emulsification to proceed. This work described that increasing domestic, separation, of driving force in the breaking area, lead to the high circulation exhaustion through the mixer area is found to be the best effect. Method of drops reduced diameter. The purpose of stirring is to format, of stable and emulsion of homogeneous by breaking large liquid drops into smaller drops. Figure 12 illustrates the proportional, volume of the emulsion as a function of stirring speed after stirring the mixture for 20 hr. The relatively, the volume of emulsion which prepared at least 1000 rpm stirring rate will decrease, sharply with time, elucidate, that a 1000 rpm was not adequate for this emulsion technique. The best display, the reliance, of emulsion stability on stirring rate, the relative emulsion volume after 20 hr, stirring followed by 10-h remain is plotted against time in Figure 12 which obviously, indicates that the stability of emulsion was accomplished with higher stirring intensity. A stirring speed higher than 3850 rpm was, however, not desired because the higher stirring intensity will drive the emulsifier to break away from the oil-water interface.

The transfer of cerium ion species into the emulsion is facilitated due to reducing in viscosity by rising temperatures. Then, the stability of the emulsion is reduced at increasing temperatures. Figure 13 compares the removal efficiency at five different temperatures of 25, 35, 45, 65, and 75◦C. Figure 13 shows that the maximum extraction qualification, are obtained at lower temperatures. Then, the maximum extraction efficiency at temperature is lower than that at 25◦C that indicates the surrounding temperature is optimal for this process.

The effect of mixing time MT on the emulsion stability was tested. Experiments under optimal conditions used were corresponding, to those used formerly. The MT was different, from 0 to 35 min. Figure 14 displays the effect of MT on the stability of the emulsion. The data indicate that the (%E) of the emulsion increases with increasing the mixing time, emulsion stability decreased. This experiment also has seen that the mean size (d₃₂) of the particles decreased very rapidly in the first few seconds and then progressively, acquire, the limiting value after 18 min. To best seen the subjection of emulsion stability on mixing time, the comparative emulsion volume after one day is versus against mixing time in Figure 14 which distinctly indicates that the optimal mixing time is 18 min.