JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2017
·
IF 4.233
Chenhu Zhang,Sun Wei,Yuehua Hu,Honghu Tang,Jiande Gao,Zhigang Yin,Qingjun Guan
Selective adsorption of tannic acid (TA) on calcite surfaces and the implications of this process for the separation of fluorite ore were studied by microflotation tests, surface adsorption experiments, zeta potential measurements, UV–vis analysis, and X-ray photoelectron spectroscopy (XPS) analysis. The microflotation tests indicated that TA, when added before sodium oleate (NaOl), could selectively depress calcite from fluorite at pH 7. Surface adsorption experiments revealed that TA hinders the interaction of NaOl with calcite. The zeta potential of calcite became more negative with TA than with NaOl. However, the characteristic features of TA adsorption were not observed on fluorite, suggesting that the dominant adsorption sites are dissimilar on the fluorite and calcite surfaces in the pulp. UV–vis spectroscopy, XPS, and solution chemistry analysis were utilized to obtain a better understanding of the mechanism for selective adsorption of TA as well as the key factors determined by the Ca 2+ and Ca(OH) + components on the mineral surfaces. A possible adsorption mechanism along with an adsorption mode is proposed for the surface interaction between TA and calcite.
研究领域:
矿物加工工程
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表面化学
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胶体与界面科学
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资源利用
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浮选化学
✓ 已验证
DOI
高影响因子
RSC Advances
·
2015
·Vol. 5
·期 118
·97435-97445
·
IF 3.84
Yuling Cai,Liuchun Zheng,Zhanqiang Fang
To reduce costs and improve practicability, an ion imprinted magnetic chitosan (IMCS) was synthesized through co-precipitation using steel pickling waste liquor and chitosan and Cu(II) as template ions, which was then characterized by TEM, SEM, EDX, FTIR, XRD and VSM. The batch experiments were carried out for its potential application and high selectivity of Cu(II) removal, which were observed due to the paramagnetic properties and coordination reactions in the imprinted cavities. Kinetic studies revealed that the adsorption process followed a pseudo second-order model and the equilibrium data fit perfectly with the Langmuir isotherm model. The maximum adsorption capacity was 109.89 mg g−1. Negative values for ΔH0 and ΔG0 indicated an exothermic and spontaneous adsorption process. The adsorption process was found to be a chemical reaction and coordination complexes were formed between the metal ions and the groups of chitosan binding mainly in the “bridge model”. Moreover, 0.2 mol L−1 HCl solution was considered as the most appropriate eluent for regeneration. It showed a great performance in the experiments for practical copper wastewater and the process was considerably cost-effective.
研究领域:
环境化学
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材料科学
·
污染控制工程
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资源循环利用
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吸附技术
✓ 已验证
DOI
高影响因子
ADVANCED POWDER TECHNOLOGY
·
2022
·Vol. 33
·期 9
·103725
·
IF 4.969
Ling Ding,Xiaolin Liu,Shuai Zhang,Jun Liao,Yong Zhang,Lin Zhang
The spinel composite doped with TiO 2 (TiO 2 @ZnFe 2 O 4 ) was prepared via in situ fabrication and template method to extract uranium(VI) from solution. Compared with ZnFe 2 O 4 and TiO 2 /ZnFe 2 O 4 , TiO 2 @ZnFe 2 O 4 showed a high adsorption efficiency (98.3%) and adsorption capacity (716.2 mg g −1 ), which mainly related to the uniform porous structure of TiO 2 @ZnFe 2 O 4 . After five adsorption–desorption cycles, the removal efficiency of TiO 2 @ZnFe 2 O 4 remained above 90%, indicating that TiO 2 @ZnFe 2 O 4 had excellent reusability. Besides, TiO 2 @ZnFe 2 O 4 possessed excellent adsorption selectivity for uranium(VI) in the existence of competitive ions. The Langmuir adsorption model and pseudo-second order model fitted well the adsorption process, which demonstrated that the remove behavior of uranium(VI) on TiO 2 @ZnFe 2 O 4 was a monolayer chemisorption process. The extraction behavior of TiO 2 @ZnFe 2 O 4 for uranium(VI) was mainly attributed to electrostatic attraction, complexation reaction and oxygen vacancy filling. This study not only provides a high efficiency adsorbent (TiO 2 @ZnFe 2 O 4 ) for the extraction of uranium(VI) from solution but also offers a new effective way to enhance the performance of spinel composite.
研究领域:
环境化学
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核化学
·
材料科学
·
吸附科学
·
水处理技术
·
功能材料
✓ 已验证
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2017
·
IF 6.065
Li Fang,Liang Li,Zan Qu,Haomiao Xu,Jianfang Xu,Naiqiang Yan
A novel method was developed and applied for the treatment of simulated wastewater containing multiple heavy metals. A sorbent of ZnS nanocrystals (NCs) was synthesized and showed extraordinary performance for the removal of Hg 2+ , Cu 2+ , Pb 2+ and Cd 2+ . The removal efficiencies of Hg 2+ , Cu 2+ , Pb 2+ and Cd 2+ were 99.9%, 99.9%, 90.8% and 66.3%, respectively. Meanwhile, it was determined that solubility product ( K sp ) of heavy metal sulfides was closely related to adsorption selectivity of various heavy metals on the sorbent. The removal efficiency of Hg 2+ was higher than that of Cd 2+ , while the K sp of HgS was lower than that of CdS. It indicated that preferential adsorption of heavy metals occurred when the K sp of the heavy metal sulfide was lower. In addition, the differences in the K sp of heavy metal sulfides allowed for the exchange of heavy metals, indicating the potential application for the sequential removal and separation of heavy metals from wastewater. According to the cumulative adsorption experimental results, multiple heavy metals were sequentially adsorbed and separated from the simulated wastewater in the order of the K sp of their sulfides. This method holds the promise of sequentially removing and separating multiple heavy metals from wastewater.
研究领域:
环境科学
·
环境工程
·
纳米材料
·
水污染控制
·
化学工程
✓ 已验证
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2021
·
IF 10.588
Keng Xuan,Juan Wang,Zhiheng Gong,Xuegang Wang,Jun Li,Yadan Guo,Zhanxue Sun
In this work, nanoscale hydroxyapatite (HAP)-modified ZIF-67 composite, HAP/ZIF-67, with abundant functional groups for uranium(VI) binding was synthesized via a facile ultrasound-assisted synthesis method. The prepared HAP/ZIF-67 was characterized by XRD , SEM, TEM , BET, FT-IR and XPS techniques, and was applied to eliminate uranium(VI) from aqueous solutions under various conditions, i.e., pH, coexisting ions, temperature and contact time. The results indicate that the abundant Co-OH, -C N- and -NH- binding groups originating from the ZIF-67 and the Ca-OH and PO 4 3- derived from loaded nanoscale HAP synergistically endowed HAP/ZIF-67 with the excellent U(VI) adsorption capacity of 453.1 mg/g, which is 2.55 and 1.78 times that of pristine HAP and ZIF-67. HAP/ZIF-67 showed high adsorption selectivity toward U(VI), and the U(VI) elimination efficiency for real wastewater by HAP/ZIF-67 reached 97.29%. The adsorption kinetics and isotherms were well simulated by the pseudo-second-order model and Langmuir isotherm model, respectively, suggesting that U(VI) adsorption was an endothermic monolayer chemisorption process. The adsorption mechanism of U (VI) by HAP/ZIF-67 was dominated by surface complexation process. This work is expected to provide an effective strategy for developing HAP-modified MOFs absorbent to be used for the highly efficient elimination of radionuclides from wastewater.
研究领域:
环境科学
·
材料科学
·
核化学
·
水污染控制
·
吸附技术
·
功能材料
·
放射性核素去除
✓ 已验证
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2019
·
IF 5.383
Xiaoyu Zhao,Guangyu Li,Minghui Feng,Yanfei Wang
Compared to traditional extraction of lithium using solar evaporation, the electrochemical extraction is advantageous in many aspects, including elevated efficiency, superior selectivity, and low environmental pollution. In this study, LiNi 0·038 Mo 0·012 Mn 1·95 O 4 (LNMMO) with good lattice structure and nano morphology was successfully prepared and confirmed by XRD (X-ray diffraction), SEM-Mapping (scanning electron microscope mapping), SEM (scanning electron microscope), and EDX (Energy-dispersive X-ray spectroscopy) analyses. The pairing of LNMMO with activated carbon (AC) yielded obvious cost-effective and environmentally friendly composite when compared to conventional Noble metals used for battery anodes, such as Ag and Pt. A hybrid supercapacitor was assembled using delithiated LNMMO cathode (NMMO) and AC anode to form NMMO/AC. The cell showed high capacity, high rate performance, and excellent cyclic stability. A continuous flow NMMO/AC hybrid supercapacitor (CF-NMMO/AC) was developed for selective capture of Li + in aqueous solution by combining NMMO/AC hybrid supercapacitor with self-designed continuous flow control system. The device delivered high Li + extraction efficiencies reaching 14.4 mg/g per one cycle in simulated brine by consuming only 7.91 W h/mol Li + . The overall process produced 97.2％ Li + in simulated brine at optimized operating conditions. Overall, CF-NMMO/AC system provided higher efficiency, superior selectivity, and moderate energy utilization for Li + recovery from brine.
研究领域:
电化学
·
环境科学
·
材料科学
·
能源工程
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分离科学
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可持续技术
✓ 已验证
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2023
·
IF 6.7
Shijie Sun,Baijin Li,Wei Xiong,Boyu Fu,Yong Zhang,Zilin Ruan,Lei Gao,Xiaoqing Zuo,Jianchen Lu,Jinming Cai
Supramolecular self-assembly offers a feasible route for nanopatterning and functionality. The construction and precise control of selective adsorption at the molecular scale play essential roles in fundamental sciences and practical applications. Molecular tiling such as trihexagonal tiling Kagome networks has potential promising chemical and physical properties. Distorted Kagome-like networks controllable fabrication is possible by coupling molecular functional groups and substrate atoms. A chiral Kagome-like network was constructed using IFDO ([1,2-b]fluorene-6,12-dione) as precursor molecules complemented with molecular beam epitaxy and annealing strategies. Revealing arrangements of the assembled network of O-Cu metal coordination linked Kagome-like networks on the Cu(1 1 1) surface and their assembly mechanisms and cavity characteristics were explored in detail through scanning tunneling microscopy combined with density functional theory. Based on the electronic state difference between the hole center of the network and the molecular backbone, the host–guest network was successfully prepared by co-depositing C 60 molecules. Kagome-like networks could as an efficient template for regulating the adsorption configuration of C 60 . Our results demonstrate a controllable and efficient method to design atomically precise ordered host–guest assemblies on solid surfaces, advancing the approach is yet another step toward the fabrication of molecular devices.
研究领域:
表面科学
·
纳米材料学
·
超分子化学
·
凝聚态物理
·
分子自组装
·
扫描探针显微学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）