Phase diagrams of new aqueous phase systems composed of aliphatic alcohols, salts and water

Greve, Arend; Kula, Maria‐Regina

doi:10.1016/0378-3812(91)87005-t

Cited by 50 publications

(28 citation statements)

References 5 publications

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“…Particularly, for the systems composed of K 2 HPO 4 and K 3 PO 4 , the alcohol with a branched-alkyl chain, 2-propanol, is less effective for undergoing liquid-liquid demixing, when compared with its isomer, 1-propanol. These results are in good agreement with the literature (Greve & Kula, 1991;Ooi et al, 2009;Shekaari, Sadeghi, & Jafari, 2010;Zafarani-Moattar, Banisaeid, & Beirami, 2005), where ternary systems based in the same alcohols and organic citrate salts (sodium-and potassium-based) were used. This trend can be explained by the higher hydrophobicity of 1-propanol.…”

Section: Phase Diagram and Tie-linessupporting

confidence: 92%

Increased significance of food wastes: Selective recovery of added-value compounds

Reis

Santos

et al. 2012

Food Chemistry

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A single-step selective separation of two food additives was investigated using alcohol-salt aqueous two-phase systems (ATPS). The selective partitioning of two of the most used additives from a processed food waste material, vanillin and l-ascorbic acid, was successfully accomplished. The results obtained prove that alcohol-salt ATPS can be easily applied as cheaper processes for the selective recovery of valuable chemical products from food wastes and other sources. As a first approach, the phase diagrams of ATPS composed of different alcohol+inorganic salt+water were determined at 298 (± 1)K and atmospheric pressure. The influence of methanol, ethanol, 1-propanol, and 2-propanol and K(3)PO(4), K(2)HPO(4) or KH(2)PO(4)/K(2)HPO(4) in the design of the phase diagrams was addressed. After the evaluation of the phase diagrams behaviour, the influence of the phase forming constituents was assessed towards the partition coefficients and recovery percentages of vanillin and l-ascorbic acid among the coexisting phases. Both model systems and real processed food waste materials were employed. Using these ATPS as partitioning systems it is possible to recover and separate vanillin, which migrates for the alcohol-rich phase, from l-ascorbic acid, which preferentially partitions for the salt-rich phase.

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Section: Phase Diagram and Tie-linessupporting

confidence: 92%

Increased significance of food wastes: Selective recovery of added-value compounds

Reis

Santos

et al. 2012

Food Chemistry

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“…Generally the ions are categorized into two types such as "kosmotropic" or "chaotropic" based on 'water structure maker' or 'water structure breaker' giving salting out and salting-in effect respectively [8,9]. Up to now, various researchers were carrying out the study of ATPS by using a phase diagram in which they used some models and equations to correlate the binodal and tie line in liquid-liquid equilibria (LLE) [10][11][12][13][14][15][16]. In recent years, several researchers focused on the measurement and investigation of thermodynamics of ATPSs composed of an aqueous solution of a short chain aliphatic alcohol in the presence of an electrolyte [10,11,[17][18][19][20][21].…”

Section: Introductionmentioning

confidence: 99%

Volumetric and compressibility studies and phase equilibria of aqueous biphasic systems of alcohols using phase diagram

et al. 2019

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The solubility data of Na 2 S 2 O 3 ·5H 2 O in various concentrations of water and ethanol/1-propanol/2-propanol/2-methyl-2-propanol have been obtained to plot triangular phase diagrams and to determine the liquid-liquid-solid equilibria at 298.15 K. The density and sound velocity measurements were carried out for binary systems (water-salt, water-ethanol/1propanol/2-propanol/2-methyl-2-propanol) and ternary systems (water-ethanol/1-propanol/2-propanol/2-methyl-2-propanol-Na 2 S 2 O 3 ) to investigate volumetric and compressibility properties. The obtained data was used to determine the acoustic parameters including adiabatic compressibility (β s ), excess molar volume (V E ), intermolecular free length (L f ), specific acoustic impedance (Z), relative association (R A ), solvation number (S n ) of water-alcohols, water-salt and water-alcohol-salt at 298.15 ± 0.05 K to evaluate equilibrium effects. Based on which, the salting-out of studied alcohols and phase forming ability of Na 2 S 2 O 3 through its bond making and breaking properties, intermolecular interactions were reported. The density, sound velocity and adiabatic compressibility of ternary system suggest phase separation phenomenon is bond breaking and bond making process with hydrogen bonding and hydrophobic interaction. The phase formation ability of systems composed of different alcohols is in order of 2-methyl-2-propanol > 1-propanol > 2-propanol > ethanol.

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“…All presented jua saponins partition coefficient range from 5 to 26, probably forming mixed micelles, where surface tension and CMC are lower than in the micelles generated by each surfactant individually [35], though with lower results than with TOPEO.…”

Section: Alternatives To Topeomentioning

confidence: 88%

Recovery of Saponins from Jua (Ziziphus joazeiro) by Micellar Extraction and Cloud Point Preconcentration

Ribeiro

Barreto

Coelho

2013

J Surfact & Detergents

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Juá (Ziziphus joazeiro) is a Brazilian plant and its bark has been used as a detergent and phytotherapic due to its high saponin content (2–10 %). Saponins are triterpenic glycosides with some properties that aid their use in food, cosmetic and pharmaceutical industries. The object of the present work was to develop an extraction and concentration process of saponins from jua bark, using green solvents such as water and ethanol. Firstly, the extraction conditions optimization was carried out using a central composite design, and compared with other methods such as Soxhlet, ultrasound‐assisted extraction and micellar extraction. Then, cloud point preconcentration was tested to select the salt type and its concentration which promotes a higher concentration factor and partition coefficient at room temperature. Finally, the removal of a t‐octyl phenol ethoxylate (9–10 EO) nonionic surfactant by adsorption was evaluated by optimizing the adsorbent type and its concentration, temperature and time of adsorption, in addition to the adsorbent recycling. Orbital shaker extraction leads to a recovery of 45.6 % saponins under the following conditions: temperature, 38.8 °C; jua/solvent ratio, 0.272; stirring speed, 300 rpm; extraction time, 2 h. Under these conditions, saponins recovery reached 90.8 % when using 15 % v/v of the nonionic surfactant, and a preconcentration factor of 14.2 was obtained by adding sodium carbonate 20 % w/v. The preconcentration factor decreased to a value of 10.1, after nonionic surfactant removal by a hydrophobic crosslinked polystyrene copolymer resin.

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Phase diagrams of new aqueous phase systems composed of aliphatic alcohols, salts and water

Cited by 50 publications

References 5 publications

Increased significance of food wastes: Selective recovery of added-value compounds

Increased significance of food wastes: Selective recovery of added-value compounds

Volumetric and compressibility studies and phase equilibria of aqueous biphasic systems of alcohols using phase diagram

Recovery of Saponins from Jua (Ziziphus joazeiro) by Micellar Extraction and Cloud Point Preconcentration

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