Studies on solubility of uranyl complexes in supercritical carbon dioxide and its controlling factors using UV-visible and¹⁷O- and¹⁹F-NMR spectroscopy

Abstract

ARTICLEStudies on solubility of uranyl complexes in supercritical carbon dioxide and its controlling factors using UV- ). The number of yl-oxygen and fluorine atoms also affected the solubility, i.e. the solubility increased in order of Cu(hfa) 2 H 2 O 5 VO(hfa) 2 H 2 O (2.5 6 10 72 M) 5 UO 2 (hfa) 2 H 2 O and in order of Cu(hfa) 2 (2.9 6 10 72 M) 5 Cr(hfa) 3 (3.0 6 10 72 M) 5 Zr(hfa) 4 (4.4 6 10 72 M). Moreover, the intermolecular interactions between CO 2 and specific atoms (yl-oxygen and fluorine) in b-diketonato complexes were examined by 17 O-and 19 F-NMR chemical shifts, and the existence of the apparent van der Waals interactions between CO 2 and the specific atoms was identified. These results showed that the solubility of b-diketonato complexes in scCO 2 was mainly controlled by the strength of CO 2 -complex interactions.

Multinuclear NMR Studies on Lewis Acid–Lewis Base Interactions between Bis(pentafluorophenyl)borinic Acid and Uranyl β-Diketonato Complexes in Toluene

“…onto the solution prepared by dissolving UO 2 (NO 3 ) 2 ·6H 2 O in 17 O-enriched water (H 2 17 O 30–40%; Cambridge Isotope Lab., Inc.) for 30 min . The U 17 O 2 (dfh) 2 DMSO complex was synthesized according to a previous paper . The CH 2 Cl 2 solution containing DMSO and Hdfh was dropped into the aqueous solution, dissolving U 17 O 2 (NO 3 ) 2 ·6H 2 O, followed by shaking to extract U 17 O 2 (dfh) 2 DMSO to the CH 2 Cl 2 phase.…”

“…In 19 56 The U 17 O 2 (dfh) 2 DMSO complex was synthesized according to a previous paper. 57 The CH 2 Cl 2 solution containing DMSO and Hdfh was dropped into the aqueous solution, dissolving U 17 O 2 (NO 3 ) 2 •6H 2 O, followed by shaking to extract U 17 O 2 (dfh) 2 DMSO to the CH 2 Cl 2 phase. After evaporation of the CH 2 Cl 2 phase, yellow precipitates were obtained and recrystallized from CH 2 Cl 2 .…”

“…57,58 11 B, 17 O, and 19 F NMR spectra were measured by using a JEOL JNM-LA300 spectrometer without spinning at 300.0, 96.3, 40.6, and 282.2 MHz, respectively; a zirconia sample tube prepared for studying the behavior of UO 2 (dfh) 2 DMSO in supercritical CO 2 was used to refer to the previous NMR data. 57 After sample solutions were placed in the zirconia sample tube, the tube was sealed with a stainless sample holder and O-ring in a glovebox filled with Ar gas. The temperature of the zirconia sample tube was controlled by the temperature controller of the NMR probe.…”

Super-Critical Fluid: An Overview on Analytical Applications

“…Hence the chelating agents used in the for-metal cations are very proper towards SFE. By altering the temperature gradient and the pressure more efficient selective and replacement over the conventional methods has been utilized for the metal ions as an ecofriendly technique [85]. SC-CO 2 extraction can provide an efficient and specific method for the separation of metal in various samples.…”

17o NMR

“…Zanonato et al 160 have identified several uranylperoxide-carbonate complexes in solution, proposed models of their structure and determined the values of their equilibrium formation constants. Moreover, the solubility and the intermolecular interaction of several uranyl and vanadyl complexes with CO 2 have been investigated in supercritical carbon dioxide, 161 using an NMR spectrometer equipped with a high pressure cell.…”