Temperature changes in solvent extractions of cadmium oxinate

Linear Solvation Energy Relationship (LSER) Analysis of Liquid–Liquid Distribution Constants of 8-Hydroxyquinoline and Its Derivatives

“…At a constant ionic strength (0.1 M NaClO 4 ) of the aqueous phase, the enthalpy and entropy of 8-hydroxyquinoline distribution depend on the properties of organic solvents and differ from those which are characteristic for 2-methyl-8-hydroxyquinoline in the system with 1,1,2,2-tetratrochloroethane. , Sporadically, the distribution constants of the other 8-hydroxyquinolinols were determined at the different ionic strengths of the aqueous phase and lower or higher temperatures than 298 K. ,,,,,,,,, As a result, the effect of temperature upon the distribution constants of different 8-hydroxyquinolinols has been expressed according to the following model: log nobreak.25em K normalD = normalϕ [ true( normalH normalL normalB , normalH normalL normalB 2 , I 1 / 2 false( 1 + I 1 / 2 false) , I , I 2 , normalπ * , normalα , normalβ , δ H 2 true) / T ] …”

“…The structures and names of considered 8-quinolinols are indicated in Appendix A. The distribution constants of 8-hydroxyquinoline and its derivatives determined experimentally in organic solvent/water and/or organic solvent/aqueous solution systems ,− are collected in Tables and .…”

Homogeneous Liquid-Liquid Extraction of Metal Ion Utilizing Upper Critical Solution Temperature of Propylene Carbonate

“…If chelate complex formation is exothermic, metal extraction is suppressed along with the increase of temperature and vice versa. Thus decreasing the distribution ratios along with increasing temperature has been reported for several extraction systems, such as extraction of silver(I) with dithizone chloroform(CHCl 3 ) solution, silver(I) and cadmium(II) with 8-quinolinol in CHCl 3 [15] , and lanthanides with N,N-Diisobutyl-2-[octyl-(phenyl)-phosphoryl]-acetamide (CMPO). [16] The values of enthalpy in Kelex100 extraction from NaOH solution, of which the extraction process was described by Equation (2), were determined to be −43 kJ mol −1 and −104 kJ mol −1 for Al 3+ and Ga 3+ , respectively, and the distribution ratio for both metal ion diminished with increase of temperature.…”

Thermodynamic Study on the Synergistic Extraction of Cobalt(II) with Acetylacetone and Trioctylphosphine Oxide

“…The absorbance of acetylacetone remaining in the organic phase at a wavelength of 279 nm was also measured with a spectrophotometer. The distribution ratio (D HR ) of acetylacetone is defined as (1) where Abs initial and Abs org are the absorbance of organic phase before shaking and the absorbance of organic phase after shaking, respectively.…”

“…Hellwege and Schweitzer examined the temperature effect on the extraction of cadmium(II) with 8-quinolinol, and reported that the enthalpy and entropy changes for all elementary steps in the extraction system. 1 By using thermodynamic quantities, Kandil et al indicated that the synergistic effect of tributylphosphate (TBP) on the extraction of lanthanides with 2-thenoyltrifluoroacetone (TTA) is caused by an expansion of the coordination number of the lanthanides ion. 2 In previous work, the authors studied the synergistic extraction of cobalt(II) with TTA and trioctylphosphine oxide (TOPO) thermodynamically, and the mechanism for the adduct-formation was clarified to proceed according to the expansion of the coordination number of cobalt(II).…”