ZEITSCHRIFT FUR PHYSIKALISCHE CHEMIE-INTERNATIONAL JOURNAL OF RESEARCH IN PHYSICAL CHEMISTRY & CHEMICAL PHYSICS
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2020
·Vol. 235
·期 4
·451-466
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IF 2.03
Yuli Xue,Yan Zhang,Xiaoling Tan,Wenqing Li,Zhongshu Li,Shaonan Xu,Peng Zhang,Jian Wang,Peiping Zhang,Shiding Miao
It is of importance to reclaim single-salt of potash from Li + -type brines of low concentration. In this work the potassium salts KHCO 3 was efficiently separated from the lithium carbonate-type brines with the aid of CO 2 carbonation. The phase field was provided in which the precipitation of KHCO 3 occurs and single-salt of potassium can be obtained. The low concentration of [Li + ] was also successfully concentrated to a high level (8.1 g/L), and this concentration can be used as sources for Li + -salts production using pre-developed strategies, which looks forward wider applications of the lithium resources of natural brine. This state-of-art was traced via isotherm evaporation on the quaternary system of Li + –K + –CO 3 2− –H 2 O at 298.15 K in which the carbonation steps were performed by CO 2 . Metastable phase diagram was found to consist of three invariant points, seven univariant curves, and four crystallization fields corresponding to Li 2 CO 3 , KHCO 3 , potassium carbonate sesquihydrate (K 2 CO 3 ⋅ 3/2H 2 O), and a potassium carbonate and potassium bicarbonate double salt (K 2 CO 3 ⋅ 2 KHCO 3 ⋅ 1.5H 2 O). There was no crystallization field corresponding to LiHCO 3 . The pH-composition diagram and density-composition diagram were also plotted. This work was carried out in aim of extracting/separating single salts of alkali metals from carbonate-type brines of west China.
研究领域:
化学工程
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材料科学
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DOI
高影响因子
LANGMUIR
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2024
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IF 3.7
Qiongyuan Zhang,Yanping Wang,Jilong Han,Haining Liu,Huifang Zhang,Zhijian Wu,Siyuan Zhang,Wenjie Han,Xiushen Ye
Layered double hydroxides (LDHs) have garnered significant attention from researchers in the field of adsorption due to their unique laminated structures and ion exchange properties. LDHs with various anion intercalation showed different adsorption effects on adsorbing ions, but the corresponding adsorption mechanisms are ambiguous. In this study, three types of NiAl-LDHs were synthesized, utilizing NO3–, CO32–, or Cl– as the interlayer anions. Batch tests were conducted to study their adsorption performances for Br–. Among them, the LDH with a NO3– intercalation layer exhibited the highest adsorption capacity for Br–, reaching up to 1.40 mmol g–1. The adsorption kinetics, mechanism, and renewability of these NiAl-LDHs were systematically compared. As a result, the type of Br– adsorption by all three materials was single molecular layer chemisorption. Moreover, the thermodynamic results of adsorption suggested that the adsorption of Br– was a spontaneous exothermic process. X-ray photoelectron spectroscopy, X-ray diffraction, and point of zero charge analysis collectively indicated that the adsorption of Br– by LDHs primarily occurred through interlayer ion exchange and electrostatic interactions. Structural characterizations of the adsorbents revealed that Br– entered the interlayers of the three LDHs, causing varying degrees of reduction in the interlayer spacing. Density functional theory calculations indicated that the interlayer binding energy of LDH with NO3– intercalation was the lowest, thereby making it more susceptible NO3– to be exchanged with Br–. Finally, the stability of the NiAl-LDHs was studied. The NiAl-LDHs retains a high removal efficiency of Br– even after 5 cycles of adsorption and desorption.
研究领域:
环境科学
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材料科学
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化学工程
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表面化学
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产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2018
·
IF 6.735
Linghui Zhao,Yufan Chen,Yong Feng,Deli Wu
In this study, three GR/Cu(II) (Green Rust/Cu(II)) composites (GR SO4 /Cu(II), GR CO3 /Cu(II), and GR Cl /Cu(II)) were synthesized and used to activate dioxygen under weakly acidic conditions. The change in the mechanism caused by three interlayer anions, CO 3 2− , SO 4 2− , and Cl − , was discussed for the first time. Both Cu(I) and H 2 O 2 were generated during GR/Cu(II)-induced dioxygen activation, resulting in the rapid degradation of acetaminophen. The inconsistency between the reaction constant rates and oxidation reduction potential (ORP) order revealed the effects of the various types of interlayer ions. To further reveal the effects of the anions, the variations in the morphology and valence states of the composites were examined. To identify the rate-controlling step of dioxygen activation by the three composites, the production of reactive oxygen species (ROS) was investigated and compared. The combination of interlayer anions and metal ions changed the oxide morphology of the solid-phase materials. Furthermore, changes in the content of the reductive species (Fe(II) or Cu(I)) either enhanced or inhibited specific reaction steps. The results from this study could deepen our understanding of the effects of anions on dioxygen activation by transition metals and provide a basis for the study of oxidation reactions and mechanisms in the presence of various anions.
研究领域:
环境科学
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化学
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2021
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IF 7.312
Yu Liu,Yu Xiang,Hui Xu,Huili Li
Photocatalysis is highly efficient for the treatment of dyeing wastewater. However, the wastewater still contains a large amount of nano-TiO 2 after photocatalysis. In order to reduce the cost of nano-TiO 2 , different coagulants were used to improve the solid/liquid separation efficiency. At the same time, the reuse of flocs has raised increasing attention after coagulation. In this study, we report on the recycling of flocs for the production of AlCl 3 and TiO 2 formed flocs (AT 1 ) and Al 13 and TiO 2 formed flocs (AT 2 ) through a simple calcination process. Results indicated the flocs formation processes under different concentration of CO 3 2– were Al species distribution and coagulant dosage dependent. Without HA molecules, the reaction between Al-based coagulants and CO 3 2– are the controlling steps in the coagulation process, and Al a and Al b species had different reaction processes. The influence of HA molecules was also studied, and the HA-Al aggregates which could bridge the TiO 2 nanoparticles , and thus induce sweep flocculation . Consequently, highly enhanced aggregation rate, due to the heteroaggregation between these aggregates and TiO 2 was observed. After calcination, the AT 2 -10 and AT 2 -20 (CO 3 2– : 10, 20 mmol/L) with petal-like structures (mesoporous), relatively high specific surface areas, i.e. 83.98 m 2 /g and 78.38 m 2 /g and high photocatalytic degradation, i.e. 72.79%, 67.78% (compared to nano-TiO 2 , AT 1 -10 and AT 1 -20), were obtained. Additionally, oxygen vacancy (OV) was generated on the surface of the recycled AT 2 -10 and AT 2 -20, which display strong photocatalytic performance for the degradation of MO greater than 65%, under ultraviolet (UV) irradiation and without any sacrificial reagents. This study proposes a new perspective on recycling coagulated flocs for practical application in wastewater treatment .
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CHEMICAL AND ENGINEERING DATA
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2019
·
IF 2.298
Zhongshu Li,Yuli Xue,Xiaoling Tan,Wenqing Li,Shaonan Xu,Ziyan Wang,Jian Wang,Lina Li,Shiding Miao
It is of great importance to separate potassium salts from carbonate-based lakes, especially the low-[K+] but high-[Na+] brine which has been discovered around the world. Here the phase diagram of the quaternary system Na+, K+//Cl–, CO32––H2O was experimentally studied at 298.15 K via the method of isothermal evaporation, and the results corrected the previous diagram reported by Blasdale (J. Am. Chem. Soc.1923, 45, 2935–2946). The type of salts appeared and their solubility during the evaporation, and the density vs composition diagram and the pH values were plotted based on the experimental data. It was found that there were six invariant points, seven univariant curves, and five crystallization fields in the equilibrium phase diagram. To extract single-salt of potassium, certain areas in the Na+, K+//Cl–, CO32––H2O diagram were chosen to be acidified by the compressed CO2, and potassium in the form of KHCO3 was precipitated from the mother solution. The compressed CO2 was able to avoid formation of NaKCO3·6H2O during evaporation of the original system Na+, K+//Cl–, CO32––H2O. Based on experiment data, the region area for potassium salt extraction was determined, and this area was suitable for extracting K+ salts from brines with a [Na+/K+] ratio even lower than 0.44. This strategy opened a new way to recovery of potassium with a maximum yield of 59.88% from the carbonate-chloride-based brine.
研究领域:
化学工程
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）