Association of Tris(pentane-2,4-dionato)chromium(III) with Modifiers of Hydrogen-bond Donors in Supercritical Carbon Dioxide

Effects of Substituents in ß-Diketones and Their Tris-iron(III) Complexes on Partitioning between Various Micellar Phases and the Bulk Aqueous Phase

“…We used the following β-diketones (HAs): acetylacetone (2,4-pentanedione; Haa), benzoylacetone (1-phenyl-1,3-butanedione; Hbza), dibenzoylmethane (1,3- (20)cetylether;B58),andTriton X-100 (TX), were used as the micelle-forming reagents. The C12POE8wassuppliedfromNikkoChemicals,Brij35andBrij 58wasfromWakoPureChemicals,andTritonX-100wasfrom Fluka.Thereportedvaluesofthecriticalmicellarconcentration (CMC), the micelle molar volume (f), the micelle aggregation number (N), the calculated whole volume of one micelle (Vt), andthecalculatedvolumeofthecoreregionofonemicelle(Vc) forthesesurfactantsarelistedinTable1.…”

“…20 They concluded that the hydrogen-bond between the adduct-forming ligand and the coordinated oxygen atom of the metal-bonded β-diketonate anionassistedtheenhancementofextractability.Althoughthe site of hydrogen-bond in our system is not the coordinated oxygen atom, the formation of a hydrogen-bond between the coordinatedligandandtheadditionalmoleculemayalsoassist in enhancing the extractability in the Htta extraction into the presentfourmicellarphases.…”

Enhanced Extraction of Tris(pentane-2,4-dionato)cobalt(III) in Supercritical Carbon Dioxide/Water Systems by Association with Fluorinated Phenols

“…A known quantity of PhOH was introduced into the mixing cell after which compressed CO 2 (10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20)(21)(22) MPa) was added by the syringe pump and stirred with a magnetic stirrer for 1 h. An aqueous solution (1.54 cm the optical cell, the valve was closed. The solutions in the optical cell were stirred with a magnetic stirrer for 3 h and subsequently settled for 10 min.…”

“…We recently reported a significant solubility enhancement of coordinatively saturated chelates of chromium(III) and cobalt(III) in SC-CO 2 upon the addition of fluorine-containing alcohols and phenols (PhOH) as modifiers [10][11][12]. This solubility enhancement effect was ascribed to the formation of association complexes with the metal complexes via hydrogen bonding in SC-CO 2 , as revealed by Fourier transform infrared spectroscopy (FT-IR).…”

The action mechanism of ethanol in preparation of supported nano-sized Ru catalyst via supercritical fluid deposition

“…But the low solubility of most metal precursors in SCCO 2 lead to the poor metal utilization and subsequent high cost [14]. In order to solve the problem, many researchers tried to add polar solvents as co-solvents to improve the dissolution of metal precursors in SCFs [15][16][17]. The effect of polar solvent on supercritical deposition process can be reflected by critical point of binary systems [16,18] , polarity of SCCO 2 [19,20] and the interactions between polar solvents and the metal precursors [17].…”