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The solubilities of 2-naphthalenesulfonic acid monohydrate and sodium 2-naphthalenesulfonate in sulfuric acid solutions were measured at temperatures ranging from 278.15 to 338.15 K by using a dynamic method. The concentration of sulfuric acid solution ranged from 0 to 80wt%,. The solubilities of 2-naphthalenesulfonic acid monohydrate and sodium 2-naphthalenesulfonate increased with temperature, and both of them were the lowest at 70wt%, of sulfuric acid solution(w 3 0 =0.70)while the highest in pure water. The solubility data were correlated by the modified Apelblat equation. Based on the solubility difference between 2-naphthalenesulfonic acid monohydrate and sodium 2-naphthalenesulfonate, a new technique in which sodium sulfate was used to replace sodium sulfite in the neutralization reaction was developed. The suitable mole ratio of H2O to Na2SO4 in the neutralization reaction was 80:1, and that of 2-naphthalenesulfonic acid monohydrate to Na2SO4 was 3.2:1. The material balance under the suitable mole ratios was given and discussed.

In this work, solid–liquid equilibria (SLE) data for ternary sodium 1-naphthalenesulfonate + sodium 2-naphthalenesulfonate + water system was measured at (283.15, 303.15 and 323.15) K respectively. The diagrams for solid liquid phase of the ternary system were well-established by the measured solubility data. The solid phases formed in the studied system were determined by the method of Schreinemaker’s wet residue. Moreover, the density of equilibrium liquid phase was gained in the process. At each temperature, there are two pure solids forming. They are sodium 1-naphthalenesulfonate and sodium 2-naphthalenesulfonate in the ternary system. The solubility data for the ternary system were calculated and regressed by NRTL model, giving acceptable results for the investigated systems.

This study evaluated the performance of photo-Fenton reaction when it was initiated by using UV/H2O2 with steel waste, basic oxygen furnace slag (BOF slag), denoted as UV/H2O2/BOF slag process, to decompose 2-naphthalenesulfonate (2-NS) in the aqueous solution. The concentration of total organic carbon (TOC) was chosen as a mineralization index of the decomposition of 2-NS by the UV/H2O2/BOF slag process. A first-order kinetic model with respect to TOC was appropriately adopted to represent the mineralization of 2-NS by the UV/H2O2/BOF slag process. The experimental results of this study suggested that the dosages with 1.25 × 10−4 mol L−1 min−1 H2O2 and 12.5 g L−1 BOF slag loading in the solution at pH 2.5 with 120 μW cm−2 UV (312 nm) provided the optimal operation conditions for the mineralization of 2-NS yielding a 56% mineralization efficiency after 90 min of reaction time.

The adsorption behavior of 2-naphthalenesulfonate (NS) on activated carbon Chemviron Filtrasorb 400 (F 400) in different aqueous systems was investigated in this study. Adsorption technology has high potential to remove NS from aqueous solutions due to the high adsorption capacity. The adsorption capacity of the NS by F 400 is effectively improved at lower pH value and higher ionic strength. The effective diffusion coefficients can be calculated by an approximate estimation method and further used to simulate the adsorption behavior of NS in a full-scale column when combined with linear driving force model (LDF model). Satisfactory results of simulating the adsorption breakthrough curve in the full-scale column can be obtained, which was further compared with the results of the rapid small-scale column tests (RSSCTs). The methods used in this study satisfactorily simulated the experimental results for investigating the performance of NS adsorbed by activated carbon F 400. Therefore, it can directly provide the parameters for designing and simulating the adsorber systems.

This study investigates the ozonation of 2-naphthalenesulfonate (2-NS) combined with UV radiation in the electroplating solution. 2-NS is commonly used as a brightening and stabilization agent in the electroplating solution. Semibatch ozonation experiments were conducted under various reaction conditions to study the effects of ozone dosage and UV radiation on the oxidation of 2-NS. The concentrations of 2-NS were analyzed at specified time intervals to elucidate the decomposition of 2-NS. Total organic carbon (TOC) is chosen as a mineralization index of the ozonation of 2-NS. In addition, values of pH and oxidation reduction potential were continuously measured in the course of experiments. As a result, the nearly complete mineralization of 2-NS via the ozonation treatment can be achieved. The mineralization of 2-NS is found accelerated by the introduction of UV radiation and has a distinct relationship with the consumption of applied ozone. These results can provide useful information for the proper removal of 2-NS in the electroplating solution by the ozonation with UV radiation.

At pH values 5.5 and 10.3, 6-deoxy-6-diethylamino-beta-cyclodextrin (DD-beta-CD) as well as beta-CD forms 1:1 inclusion complexes with 2-anthracenesulfonate (2AS), 2-naphthalenesulfonate (2NS), 2,6-naphthalenedisulfonate (2,6NDS), and 2,7-naphthalenedisulfonate (2,7NDS). The equilibrium constants (K) for the formation of the 1:1 inclusion complexes have been evaluated from the absorbance and/or fluorescence intensity changes. With respect to the beta-CD inclusion complexes of 2AS, 2NS, 2,6NDS, and 2,7NDS, the K values at pH 5.5 are nearly the same as the corresponding ones at pH 10.3. In the case of the DD-beta-CD inclusion complexes, the K values of 2AS and 2NS similarly do not depend on the pH value. However, the K values of 2,6NDS and 2,7NDS for DD-beta-CD at pH 5.5 have been found to be more than two times greater than the corresponding ones at pH 10.3, suggesting the electrostatic attraction between the protonated diethylamino group of DD-beta-CD and the sulfonato group of the NDSs.

Cristallisation dans le systeme monoclinique, groupe P2 1/n et affinement jusqu'a R=0,053. Conformation repliee de la molecule avec les systemes cycliques presque paralleles l'un l'autre