scholarly journals Molecular Interactions in Binary Surfactant Solutions: Effect of pH

2019 ◽  
Vol 64 (4) ◽  
pp. 437-445
Author(s):  
Olga Kochkodan ◽  
Victor Maksin ◽  
Nadiya Antraptseva ◽  
Tetyana Semenenko
Keyword(s):  
Molecular Interactions ◽  
Mixed Micelles ◽  
Ph Value ◽  
Chemical Properties ◽  
Micelle Formation ◽  
Bulk Solution ◽  
Surfactant Mixtures ◽  
Solution Ph ◽  
Solution Interface ◽  
Adsorption Layers

By using surface tension and conductivity measurements, the colloid-chemical properties of the mixtures of cationic hexadecylpyridinium bromide with nonionic Triton X-100 surfactants were investigated both in the bulk solution and at air/solution interface at different pH values. The composition of mixed micelles and adsorption layers, parameters of molecular interactions in mixed micelles βm and adsorption layers βσ, as well as standard free energies of micelle formation ΔG0mic and adsorption ΔG0ads were calculated. It was found that molecules of the nonionic surfactant presumably dominate in the mixed micelles and adsorption layers. It was shown that βm and βσ have negative values, which indicate the strengthening of intermolecular interactions in the mixed micelles and adsorption layers. Based on the data obtained, it was suggested that ion-dipole interactions are involved in the formation of intermolecular structures between nonionic and cationic surfactants in aqueous solution and at the air-solution interface. It was shown that βm, βσ as well as ΔG0mic and ΔG0ads parameter depends on the solution pH value. The complex interplay of ion-dipole, protonation and chelation processes, which occur in the surfactant mixtures at different pH and affect the strength of intermolecular interaction, should be taken into account for data analysis.

scholarly journals Synergism of non-ionic and anionic surfactants in a binary solution.

2020 ◽  
Vol 11 (3-2020) ◽  
pp. 62-68
Author(s):  
A. S. Genevskaya ◽  
◽  
G. V. Mitrofanova ◽  
◽  
Keyword(s):  
Adsorption Layer ◽  
Mixed Micelles ◽  
Anionic Surfactants ◽  
Binary Solution ◽  
Micelle Formation ◽  
Ionic Component ◽  
Solution Composition ◽  
Binary Solutions ◽  
Air Interface ◽  
Adsorption Layers

Adsorption at the gas —air interface and micelle formation in binary solutions of ethoxylated alkyl phenol (Neonol AF 9-10) and sodium oleate have been studied. The Rubin and Rosen equations were used to determine the interaction parameters and the composition of mixed micelles and adsorption layers depending on the initial solution composition. The authors have found out that the micelles and the adsorption layer at the interface are enriched in a non-ionic component. The maximum synergistic effect during micelle formation was found for solutions containing 20–30 % molar of reagent Neonol AF 9-10, and during adsorption —20 and 50 %.

Adsorption of Nickel and Cobalt Ions on Magnesium Silicate

2013 ◽  
Vol 726-731 ◽  
pp. 2855-2858
Author(s):  
Hua Yang ◽  
Hai Zeng Wang
Keyword(s):  
Ph Value ◽  
Average Pore Size ◽  
Chemical Properties ◽  
Magnesium Silicate ◽  
Solution Ph ◽  
Average Pore ◽  
Cobalt Ions ◽  
Physico Chemical ◽  
Short Time ◽  
Adsorption Desorption

Magnesium silicate (MS) was successfully prepared and the physico-chemical properties were determined by N2adsorption/desorption isotherm and Scanning Electron Microscopy (SEM). Surface area and the average pore size were 120 cm3·g-1and 10 nm. Adsorption experiments of removal of nickel and cobalt ions were investigated as the function of initial concentration, adsorbent dose, adsorption time and solution pH value. The maximum removal was reached with pH equal to 5 for the removal of nickel and cobalt ions. Adsorption process was rapid and adsorption equilibriums were attained in a short time.

Study of Pb2+, Cd2+ and Ni2+adsorption onto activated carbons prepared from glycyrrhiza residue by KOH or H3PO4 activation

2015 ◽  
Vol 72 (3) ◽  
pp. 451-462 ◽  
Author(s):  
Chunfang Ma ◽  
Wei Fan ◽  
Jinbao Zhang ◽  
Yang Shi ◽  
Ningchuan Feng
Keyword(s):  
Activated Carbons ◽  
Ph Value ◽  
Raw Materials ◽  
Chemical Properties ◽  
Kinetic Studies ◽  
Physical Structure ◽  
Micropore Volume ◽  
Solution Ph ◽  
Analytical Instruments ◽  
H3po4 Activation

The activated carbons (ACs) were prepared from glycyrrhiza residue by KOH or H3PO4 activation and were used for removing Pb2+, Cd2+ and Ni2+ from simulated wastewater. The changes of the physical structure and chemical properties of the glycyrrhiza residue before and after activation were characterized by using a variety of analytical instruments and methods. Kinetics and equilibrium isotherms were obtained and the effects of solution pH value and adsorbent dosage were studied in batch experiments. The results indicated that after activation, the surface structure of glycyrrhiza residue changes and surface area, micropore volume also increase accordingly. Kinetic studies showed that the adsorption followed a pseudo-second-order reaction. The Freundlich model fitted the equilibrium data better than the Langmuir isotherm. According to the Langmuir equation, the maximum adsorption capacities of ACs prepared from glycyrrhiza residue by KOH and H3PO4 activation for Pb2+, Cd2+ and Ni2+ are 2.170 mmol/g, 2.617 mmol/g, 3.741 mmol/g and 2.654 mmol/g, 3.095 mmol/g, 3.076 mmol/g, respectively, which are much higher than ACs prepared from other raw materials.

scholarly journals Molecular Interactions in Binary Surfactant Solutions: Effect of Ionic Counterpart

2020 ◽  
Vol 64 (3) ◽  
Author(s):  
Olga Kochkodan ◽  
Nataliya Slobodianiuk ◽  
Lidiya Kovshun ◽  
Olena Hyzhan
Keyword(s):  
Sodium Dodecyl Sulfate ◽  
Molar Fraction ◽  
Sodium Dodecyl ◽  
Synergetic Effect ◽  
Micelle Formation ◽  
Surfactant Mixtures ◽  
Triton X100 ◽  
Dodecyl Sulfate ◽  
The Individual ◽  
Adsorption Layers

Abstract. The effect of intermolecular interactions on processes of micelle formation and adsorption in binary mixtures of non-ionic Triton X100 (TX100) with ionic sodium dodecyl sulfate and dodecylpyridinium bromide surfactants was studied. The ionic surfactants have identical hydrophobic alkyl chain and different hydrophilic groups. A feature of the used binary surfactant mixtures is that critical micelle concentrations and surface activity of the individual components are considerably different. A synergetic effect of decreasing of the surface tension was found in the surfactant mixtures. It was shown that the mixed adsorption layers and the micellar phases are enriched with the nonionic surfactant. For both sodium dodecyl sulfate/TX100 and dodecylpyridinium bromide/TX100 systems, the synergetic effects were most pronounced at a high molar fraction of the nonionic surfactants in the mixture. By using the Ruben-Rosen model, molecular interaction parameters in the mixed micelles βm, and in the adsorption layers βσ were evaluated. As was shown βm and βσ parameters to be notably higher for sodium dodecyl sulfate/TX100 mixture. Resumen. Se estudia el efecto de las interacciones intermoleculares en el proceso de formación y adsorción de micelas en mezclas binarias de Triton X100 (TX100), no iónico, con dodecil sufato de sodio y bromuro de dodecil piridinio, ambos iónicos, como surfactantes. Los surfactantes iónicos tienen cadenas alquílicas hidrofóbicas idénticas y grupos hidrofílicos diferentes. Una característica de las mezclas binarias de surfactantes que se utilizaron es que las concentraciones micelares críticas y la actividad superficial de los componentes individuales es considerablemente diferente. Se encontró un efecto sinérgico de decremento de la tensión superficial en las mezclas de surfactantes. Se muestra que las capas mixtas de adsorción y las fases micelares están enriquecidas con surfactante no iónico. Tanto en el sistema dodecil sufato de sodio/TX100 como en el caso de bromuro de dodecil piridinio/TX100, los efectos sinérgicos fueron más pronunciados en las mezclas con fracciones molares altas de los surfactantes no iónicos. Utilizando el modelo de Ruben-Rosen, se evaluaron los parámetros de interacción molecular en las micelas mezcladas βm y en las capas de adsorción βσ. Se muestra que los parámteros βm son βσ son notablemente mayores en la mezcla de dodecil sufato de sodio/TX100.

Influence of temperature and pH value on deposition rate and corrosion resistance of Ni–Zn–P alloy coating

2019 ◽  
Vol 33 (01n03) ◽  
pp. 1940013
Author(s):  
Yongfeng Li ◽  
Chengguo Fu ◽  
Lili Liu ◽  
Mingchao Liang ◽  
Yaming Liu ◽  
...  
Keyword(s):  
Corrosion Resistance ◽  
Deposition Rate ◽  
Ph Value ◽  
Chemical Properties ◽  
Alloy Coating ◽  
Industrial Applications ◽  
Complexing Agent ◽  
Solution Ph ◽  
Plating Bath ◽  
The Stability

The Ni–Zn–P alloy coating has excellent physical and chemical properties that have been exploited for various industrial applications. Using sodium citrate as a complexing agent and lactic acid as a stabilizer, the effects of temperature and pH on the deposition rate and corrosion resistance of electroless plated Ni–Zn–P coating were studied. The results indicated that, when the temperature was 85[Formula: see text]C, a good deposition rate was obtained with stable plating solution. pH value of 9.0 is preferred for the coating process by considering the stability of plating bath and deposition rate. The Ni–Zn–P alloy coating deposited with plating temperature of 85[Formula: see text]C and bath pH of 9.0 has good quality, and a uniform and smooth surface texture without porosity.

scholarly journals Detailed Calorimetric Analysis of Mixed Micelle Formation from Aqueous Binary Surfactants for Design of Nanoscale Drug Carriers

Nanomaterials ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 3288
Author(s):  
Ádám Juhász ◽  
László Seres ◽  
Norbert Varga ◽  
Ditta Ungor ◽  
Marek Wojnicki ◽  
...  
Keyword(s):  
Mixed Micelle ◽  
Mixed Micelles ◽  
Drug Carrier ◽  
Micelle Formation ◽  
Water Soluble ◽  
Titration Calorimetry ◽  
Surfactant Mixtures ◽  
Calorimetric Analysis ◽  
Mixed Micelle Formation ◽  
Ideal Mixing

While numerous papers have been published according to the binary surfactant mixtures, only a few articles provide deeper information on the composition dependence of the micellization, and even less work attempts to apply the enhanced feature of the mixed micelles. The most important parameter of the self-assembled surfactants is the critical micelle concentration (cmc), which quantifies the tendency to associate, and provides the Gibbs energy of micellization. Several techniques are known for determining the cmc, but the isothermal titration calorimetry (ITC) can be used to measure both cmc and enthalpy change (ΔmicH) accompanying micelle formation. Outcomes of our calorimetric investigations were evaluated using a self-developed routine for handling ITC data and the thermodynamic parameters of mixed micelle formation were obtained from the nonlinear modelling of temperature- and composition- dependent enthalpograms. In the investigated temperature and micelle mole fractions interval, we observed some intervals where the cmc is lower than the ideal mixing model predicted value. These equimolar binary surfactant mixtures showed higher solubilization ability for poorly water-soluble model drugs than their individual compounds. Thus, the rapid and fairly accurate calorimetric analysis of mixed micelles can lead to the successful design of a nanoscale drug carrier.

KARAKTERISASI SIFAT FISIKA DAN KIMIA CUKA KAYU DARI TANDAN KOSONG KELAPA SAWIT

2014 ◽  
Vol 6 (1) ◽  
pp. 35 ◽  
Author(s):  
Rizka Karima
Keyword(s):  
Specific Gravity ◽  
Physical Properties ◽  
Solid Waste ◽  
Ph Value ◽  
Total Yield ◽  
Chemical Properties ◽  
Phenol Content ◽  
Empty Fruit Bunches ◽  
Wood Vinegar ◽  
And Chemical Properties

There’s so many pal solid waste or palm empty fruit bunches, but the utilization is not maximized, this research its to optimized utilization of palm solid waste to be wood vinegar and want to know the composition physical properties and chemical properties of wood vinegar from palm empty fruit bunches. Total yield of wood vinegar from palm empty fruit bunches its 15,94 % and total yield of charcoal its 64,58 %. GCMS result showing chemical properties from wood vinegar of burning < 100oC its obtained 19 compound and burning >100 oC its obtained 6 compound. The result physichal properties testing from crued wood vinegar its obtained specific gravity 1,0005 and 1,0010, pH value are 3,233 and 3,186, TAT content are 9,36 % and 11,12 %, phenol content its 0,44 %. The result physical properties testing from wood vinegar which has decolorizatin by activated carbon its obtained specific gravity are 0,9987 and 0,999, pH value are 3,036 and 3,012, TAT content are 8,29 % and 9,27 % and phenol content its 0,01 %.Keywords: palm bunches, wood vinegar, liquid smoke

scholarly journals Separation of Radionuclides from a Rare Earth-Containing Solution by Zeolite Adsorption

Minerals ◽  
2020 ◽  
Vol 11 (1) ◽  
pp. 20
Author(s):  
Deniz Talan ◽  
Qingqing Huang
Keyword(s):  
Rare Earth ◽  
Rare Earths ◽  
Contact Time ◽  
Separation Efficiency ◽  
Ph Value ◽  
Solid Phase ◽  
Separation Performance ◽  
Solution Ph ◽  
Zeolite Sample ◽  
Alternative Sources

The increasing industrial demand for rare earths requires new or alternative sources to be found. Within this context, there have been studies validating the technical feasibility of coal and coal byproducts as alternative sources for rare earth elements. Nonetheless, radioactive materials, such as thorium and uranium, are frequently seen in the rare earths’ mineralization, and causes environmental and health concerns. Consequently, there exists an urgent need to remove these radionuclides in order to produce high purity rare earths to diversify the supply chain, as well as maintain an environmentally-favorable extraction process for the surroundings. In this study, an experimental design was generated to examine the effect of zeolite particle size, feed solution pH, zeolite amount, and contact time of solid and aqueous phases on the removal of thorium and uranium from the solution. The best separation performance was achieved using 2.50 g of 12-µm zeolite sample at a pH value of 3 with a contact time of 2 h. Under these conditions, the adsorption recovery of rare earths, thorium, and uranium into the solid phase was found to be 20.43 wt%, 99.20 wt%, and 89.60 wt%, respectively. The Freundlich adsorption isotherm was determined to be the best-fit model, and the adsorption mechanism of rare earths and thorium was identified as multilayer physisorption. Further, the separation efficiency was assessed using the response surface methodology based on the development of a statistically significant model.

Synthesis and Application of Itaconic Acid Water-Coke Slurry Dispersant

2017 ◽  
Vol 896 ◽  
pp. 167-174 ◽  
Author(s):  
Zhi Yuan Yang ◽  
Zhuo Yue Meng ◽  
Zhi Hua Li ◽  
Si Tong Wang
Keyword(s):  
Surface Tension ◽  
Polyethylene Glycol ◽  
Itaconic Acid ◽  
High Performance ◽  
Ph Value ◽  
Raw Materials ◽  
Esterification Reaction ◽  
Solution Ph ◽  
Powder Surface ◽  
Coke Powder

Polyethylene glycol (PEG-200) and itaconic acid (IA) were used as raw materials to compound macromer through esterification reaction. A new type of specialized water-coke slurry dispersant was synthesized by copolymerization of microware, sodium methallyl sulfonate (SMAS) and maleic anhydride (MA). The experiment showed that the concentration of slurry could be reached to 63% with the dosage of 0.2%, and the apparent viscosity was 1140.3 mPa∙s. Through the analysis of the infrared, the dispersant was confirmed to have polyethylene glycol branched chain and hydrophilic functional groups such as carboxyl or sulfonic group. When the concentration of dispersant was 30 g/L, the surface tension of water could be decreased from 72.70 mN/m to 45.50 mN/m. Furthermore, when the solution pH value was 9, the Zeta potential of semi-coke powder surface could also be decreased from-13.38 mV to-25 mV with the addition of dispersant. Thus, this dispersant could increase electronegativity of semi-coke powder surface, enhance steric-hindrance effect and prevent the phenomenon of powder flocculation and gather. Meantime, it also could reinforce the semi-coke hydrophilic by reducing the surface tension of water effectively. And then, the high performance water-coke slurry could be obtained.

Sign in / Sign up

Export Citation Format

Share Document