The specific heat capacity of NaBO2(aq) solution was determined using a Calvet-type calorimeter at a temperature from 288.15 to 338.15 K and at a concentration from about 0.25 mol·kg–1 H2O to near room temperature solubility limit. Combining these specific heat capacity data and thermodynamic and solid–liquid equilibrium data reported in the literature, a temperature-dependent thermodynamic model was developed for the NaBO2 + H2O system based on Pitzer–Simonson–Clegg activity coefficient equations. The model represents all of the properties over a wide temperature and concentration ranges. Combining the binary models of NaCl + H2O and Na2SO4 + H2O systems published in the previous studies of our group, multitemperature thermodynamic models of the NaBO2 + NaCl + H2O and NaBO2 + Na2SO4 + H2O systems were constructed. These ternary models reproduce the experimental solubility isotherms reported in the literature in general, but some significant inconsistency is still present. More accurate solubility data for these ternary systems at various temperatures are urgent.
Liu Min,Zhang Qiang,Gao Jianxin,Liu Qianfeng,Wang Erdong,Wang Zhenbo
Mg-air battery is a promising electrochemical system for high-energy–density, long storage application. However, its commercialization is hindered by the low anode utilization rate mainly caused by the serious hydrogen evolution reaction (HER) in traditional NaCl aqueous electrolyte. Herein, we report NaBF 4 -dimethyl sulfoxide (DMSO)/NaCl-H 2 O biphasic electrolytes to alleviate the anode HER corrosion by allowing anodic reaction to take place in organic solution DMSO while ensuring high cathode activity with applying cathode reaction to occur in NaCl-H 2 O solution. The discharge results show that its utilization rate of AZ61 alloy in NaBF 4 -DMSO/NaCl-H 2 O biphasic electrolytes is increased to 67% at 1 mA cm −2 which is 17% higher than in NaCl-H 2 O single electrolyte, and the anode energy density is up to 2020 Wh kg −1 . In addition, even at 15 mA cm −2 , its discharge voltage is still up to 1.02 V which is higher than that in similar literatures using organic electrolytes for Mg anode.
Yunxue Gao,Shuni Li,Quanguo Zhai,Yucheng Jiang,Mancheng Hu
Complete phase diagrams and physico-chemical properties for the ternary system (CsCl + NaCl + H2O) were determined at T = (298.15, 308.15, and 318.15) K, respectively. The X-ray diffraction method and Schreinemaker’s wet residue method were used to verify the solid phase. The phase diagrams show this ternary system is a complex type. Three crystallization regions were found corresponding to the single salt NaCl, a compound CsCl·2NaCl·2H2O, and a solid solution series [Cs1–x(Na·H2O)x]Cl (x in [Cs1–x(Na·H2O)x]Cl changed from 0 to 0.43 (298.15 K), 0.39 (308.15 K), and 0.36 (318.15 K) at each temperature. With rising temperature, the crystallization area of NaCl increased, but CsCl·2NaCl·2H2O and [Cs1–x(Na·H2O)x]Cl decreased simultaneously. However, density and refractive index increased with increasing CsCl concentration.
Hao Runming,Du An,Zhu Qingling,Wu Xue,Liu Sijia,Wang Ke,Wang Yang
5-Hydroxymethylfurfural (HMF) is a high value-added platform compound, converted into bio-based polyesters and biofuels etc. In this paper, we used two commercially available hexamethylenimine and cetyltrimethylammonium bromide (CTAB) as the structure-directing agents to synthesize HMWW zeolite nanosheets via one step. A series of HMWW zeolite nanosheets with different disorder index ( DI ) were controllably prepared by adjusting the amount of CTAB, operating also as an in situ exfoliating agent, converting fructose into HMF in the tetrahydrofuran/NaCl-H 2 O biphasic solvent with low boiling point. Successful construction of disordered HMWW zeolite nanosheets was verified by PXRD. Further characterizations by BET, SEM and TEM etc. show that HMWW 4.0 with the optimum DI of 0.67 has a disordered network-like arrangement of layers with the external surface area of 224 m 2 /g and the mesoporous size of 3.5 nm. Catalytic evaluations showed that HMF selectivity was closely related to DI of the catalysts. Under the optimized DI , fructose molecules are readily accessible to acidic sites on the external surface while larger external surface area is exposed. The HMWW 4.0 zeolite catalyzed fructose dehydration in the biphasic solvent, producing 90% HMF selectivity with 93% fructose conversion at 140 °C for 6 h. In the reuses of the HMWW 4.0 catalyst, HMF selectivity was around 90% with fructose conversion decreasing by ca. 10% after six runs, indicating that it possesses the promising stability. Graphical Abstract
危险品化学品经营许可证（带存储）