Solvation Of Nitrate Research Articles

Enhanced Sulfate Production by Nitrate Photolysis in the Presence of Halide Ions in Atmospheric Particles.

Heterogeneous oxidation of SO2 is an effective production pathway of sulfate in the atmosphere. We recently reported a novel pathway for the heterogeneous oxidation of SO2 by in-particle oxidants (OH, NO2, and NO2-/HNO2) produced from particulate nitrate photolysis (Environ. Sci. Technol. 2019, 53, 8757-8766). Particulate nitrate is often found to coexist with chloride and other halide ions, especially in aged sea-salt aerosols and combustion aerosols. Reactive uptake experiments of SO2 with UV-irradiated nitrate particles showed that sulfate production rates were enhanced by a factor of 1.4, 1.3, and 2.0 in the presence of Cl-, Br-, and I-, respectively, compared to those in the absence of halide ions. The larger sulfate production was attributed to enhanced nitrate photolysis promoted by the increased incomplete solvation of nitrate at the air-particle interface due to the presence of surface-active halide ions. Modeling results based on the experimental data showed that the nitrate photolysis rate constants increased by a factor of 2.0, 1.7, and 3.7 in the presence of Cl-, Br-, and I-, respectively. A linear relation was found between the nitrate photolysis rate constant, jNO3-, and the initial molar ratio of Cl- to NO3-, [Cl-]0/[NO3-]0, as jNO3- = 9.7 × 10-5[Cl-]0/[NO3-]0 + 1.9 × 10-5 at [Cl-]0/[NO3-]0 below 0.2. The present study demonstrates that the presence of halide ions enhances sulfate production produced during particulate nitrate photolysis and provides insights into the enhanced formation of in-particle oxidants that may increase atmospheric oxidative capacity.

High-efficient photooxidative degradation of dyes catalyzed by hetero-nuclear complex under light irradiation

Abstract A hetero-nuclear complex Hexakis (μ2-pyridine-2-aldoximato-N, N′, O)-iron (III) -di-nickel (II) nitrate solvate duodenaryhedrate ([FeNi2(PA)6]) has been prepared. The structure of the complex has been characterized by X-ray crystallography. The complex was observed to be active in photo-catalyzing oxidation of Rhodamine B (RhB) and Methyl Orange (MO) in an aqueous solution with hydrogen peroxide (H2O2).

Phase equilibria in the liquid ternary system [Th(NO3)4(TBP)2]-[UO2(NO3)2(TBP)2]-Isooctane at different temperatures

The phase diagrams of the ternary systems [Th(NO3)4(TBP)2]-[UO2(NO3)2(TBP)2]-isooctane in the temperature range 298.15–333.15 K were constructed. These diagrams contain the field of homogeneous solutions and the field of separation into two liquid phases (I, II). Phase I is enriched in [Th(NO3)4(TBP)2] and [UO2(NO3)2(TBP)2], and phase II is enriched in isooctane. With increasing temperature from 298.25 to 333.15 K, the mutual solubility of Th(NO3)4(TBP)2 and isooctane does not change noticeably, but the two-phase fields somewhat contract. In the two-phase systems [UO2(NO3)2(TBP)2] is preferentially distributed in phase I, although the binary system [UO2(NO3)2(TBP)2]-isooctane is single-phase over the entire temperature range examined. The preferential accumulation of [UO2(NO3)2(TBP)2] in phase I causes the redistribution of [Th(NO3)4(TBP)2] and isooctane into phases II and I, respectively. The compositions of the ternary systems in the critical points at different temperatures were determined. The electronic absorption spectra of uranyl nitrate solvate with TBP in the homogeneous and two-phase systems were recorded and analyzed.

Influence of Temperature on the Mutual Solubility of Components in the Binary Systems Tetradecane—Rare-Earth Metal (Nd, Sm, Gd, Y, Lu) Nitrate Solvate with TBP

The phase diagrams of binary liquid systems tetradecane—rare-earth metal (Nd, Sm, Gd, Y, Lu) nitrate solvate with TBP were studied in the temperature range 273.15–373.15 K. These diagrams contain the fields of homogeneous solutions and the field of separation into two liquid phases (I, II). Phases I and II are enriched, respectively, in tetradecane and Ln(NO3)3(TBP)3 (Ln = Nd, Sm, Gd, Y, and Lu). With increasing temperature, the fields of separation into two liquid phases contract. The upper critical solution temperatures are dependent on the kind of rare-earth metal(III).

Effect of temperature on solubility in liquid ternary systems tetradecane-normal carboxylic acids (or higher isomers of ?,??-branched carboxylic acids)-neodymium nitrate solvate with tri-n-butyl phosphate

Phase diagrams of ternary liquid systems tetradecane-normal carboxylic acids [or higher isomers of α,α′-branched carboxylic acids (HICA)]-neodymium nitrate solvate with tri-n-butyl phosphate were studied within the temperature range 293.15–344.85 K. The diagrams consist of the area of homogeneous solutions and area of two coexisting liquid phases (I and II). Phase I is enriched in tetradecane, and phase II, in Nd(NO3)3(TBP)3. The area of phase separation contracts with increasing temperature. The points of the critical composition of ternary systems were estimated at various temperatures. In these points, the content of normal carboxylic acids is lower than that of HICA.

Influence of temperature on phase separation in the binary system tetradecane-Nd(III) nitrate solvate with tri-n-butyl phosphate and ternary system tetradecane-tri-n-butyl phosphate-Nd(III) nitrate solvate with tri-n-butyl phosphate

The phase diagrams of the liquid binary system tetradecane-Nd(III) nitrate solvate with tri-n-butyl phosphate [Nd(NO3)3 (TBP)3] and ternary liquid system tetradecane-tri-n-butyl phosphate-Nd(III) nitrate solvate with tri-n-butyl phosphate were studied in the temperature range 298.15–344.85 K. The phase diagrams of the binary and ternary systems contain an area of homogeneous solutions and an area of separation into two liquid phases (I, II). Phases I and II are enriched in tetradecane and Nd(NO3)3 (TBP)3, respectively. With increasing temperature, the areas of separation into two liquid phases in the binary and ternary systems contract. The compositions of the binary and ternary systems in the critical points at different temperatures and their upper critical solution temperatures were determined.

Effect of Temperature on Phase Separation in Liquid Binary System Constituted by Tetradecane and Samarium(III) Nitrate Solvate with Tri-n-Butyl Phosphate and Ternary System Constituted by Tetradecane, Tri-n-Butyl Phosphate, and Samarium(III) Nitrate Solvate with Tri-n-Butyl Phosphate

The phase diagrams of a binary liquid system constituted by tetradecane and samarium(III) nitrate solvate with tri-n-butyl phosphate and a ternary system constituted by tetradecane, tri-n-butyl phosphate, and samarium(III) nitrate solvate with tri-n-butyl phosphate were studied at 298.15-355.15 K. The distribution of components between the phases was considered. The points of critical compositions of the ternary system at various temperatures and the upper critical temperature of mixing of the binary and ternary systems were estimated.

Phase Separation in the Systems Constituted by Tetradecane (Hexane, Decane), Tri-n-Butyl Phosphate, and Cerium(III) Nitrate Solvate with Tri-n-Butyl Phosphate

Phase diagrams of ternary liquid systems constituted by tetadecane (hexane, decane), tri-n-butyl phophate, and cerium(III) nitrate solvate with tri-n-butyl phosphate Ce(NO3)3(TBP)3 with phase separation into liquid phases I and II were studied at 298.15 K. Phase I is enriched in the hydrocarbon diluent, and phase II, in Ce(NO3)3(TBP)3. The distribution of components between phases I and II was considered.

Infrared study of compounds of type (MNO 3, nHNO 3)

The solvation of nitrate by nitric acid molecule is studied by infrared spectroscopy. It is shown than solvation occurs through hydrogen bonds. The solvation is “asymmetrical”, “nearly symmetrical” or “perfectly symmetrical” according to the number of nitric acid molecules.