Umur Dramur

Liquid-liquid equilibria of propionic acid - water - solvent (n-hexane, cyclohexane, cyclohexanol and cyclohexyl acetate) ternaries at 298.15 K

The experimental liquid-liquid equilibrium data on propionic acid-water-solvent ternary mixtures at a temperature of 298.15 K are presented. The solvents are n-hexane, cyclohexane, cyclohexanol and cyclohexyl acetate. The distribution coefficients and separation factors are reported. The tie line data are correlated using the methods of Othmer-Tobias and Hand. The experimental results are compared with the values predicted by the UNIFAC group-contribution method.

The Compositions of Turkish Bergamot Oils Produced by Cold-Pressing and Steam Distillation

Abstract Bergamot oil was obtained from Turkish bergamot fruit (Citus bergamia Risso et Poit.) peels by cold pressing and steam distillation. The analysis of bergamot oil was carried out by capillary GC and GC/MS. In total, 47 components were fully characterized and grouped in six component classes (monoterpenes hydrocarbons, oxygenated compounds, sesquiterpenes, carbonyl compounds, alcohols, and esters) for an easier comparison of all oils. Variations during the fruit development of the percentage of the six classes were also described. The composition varied during the season; since the reported values referred to oil obtained from ripe fruits. The main components of the cold pressed Turkish bergamot oil coming from ripe fruits were limonene (37.2%), linalyl acetate (36.3%), linalool (7.9%), γ-terpinene (5.9%), β-pinene (3.9%) and myrcene (1.3%). The concentation of linalyl acetate was maximum level when the bergamot fruits reached full maturity characterized by a yellow coloration.

Predicting Liquid–Liquid Equilibria of Amine Extraction of Carboxylic Acid Through Solvation Energy Relation

Abstract Long‐chain, aliphatic tertiary amines (e.g., Alamine 336 or 308) dissolved in suitable organic solvents are known to be effective extractants for carboxylic acids. A log‐basis approach SERAS (solvation energy relation for amine systems) has been proposed to estimate the properties and liquid–liquid equilibria (LLE) of amine/diluent/organic acid associated systems containing protic and nonprotic components. The model combines the solvatochromic parameters of solvation energy of solution with the thermodynamic factors derived from a group‐contribution method, i.e., UNIFAC‐Dortmund activity‐coefficient model. The reliability of the model has been analyzed against the LLE data for distribution of pyruvic (2‐oxopropanoic) acid between water and Alamine 308 (triisooctylamine) dissolved in C6‐ring‐included diluents of proton‐donating and ‐accepting (cyclohexanone, methylcyclohexanol), polar (1,2‐dichlorobenzene), and inert (toluene) types. The proposed solvatochromic approach SERAS is expected to be an improvement in data fit clarifying the simultaneous impact of hydrogen bonding, solubility, and thermodynamic factors of components on LLE. The model matches the experimental data, yielding a mean relative error of ±13.9%. The results were also correlated using a version of the mass‐action law, i.e., a chemodel approach comprising the formation of one or two acid–amine complexes.

Volatile Constituents of Turkish Bergamot Oil

Abstract The analysis of bergamot (Citrus bergamia Risso et Poiteau) oil of Turkish origin was carried out by capillary GC and GC/MS. Forty-nine compounds, constituting 99-4% of the oil, were identified. The composition of the Turkish bergamot oil was compared with the Italian bergamot oil. They could be differentiated from their sesquiterpenes, carbonyl compounds, hydrocarbons and monoterpenes. The main components of die Turkish bergamot oil were linalyl acetate (38.7%), limonene (23.7%), linalool (14.7%), γ-terpinene (4.7%), β-pinene (3.0%) and myrcene (2.0%). The bergamot oil yield was about 1.2% for fresh bergamot rinds.