International Journal of Mining Science and Technology
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2023
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IF 11.8
Haoyong Yu,Yangge Zhu,Liang Lu,Xiaoxing Hu,Songqing Li
This study aims to investigate the effect of a cationic-anionic mixed collector (dodecyltrimethyl ammonium bromide/sodium oleate (DTAB/NaOL) on the selective separation of apatite, dolomite, and potassium feldspar. Herein, several experimental methods, including flotation experiments, zeta-potential detection, microcalorimetry detection, XPS analysis and FTIR measurements, were used. The flotation tests showed that dolomite and potassium feldspar can be successfully removed from apatite simultaneously when the molar ratio of DTAB to NaOL was 2:1 with pH 4.5. Zeta-potential and microcalorimetry detection suggested that NaOL and DTAB were adsorbed on the surface of dolomite and potassium feldspar respectively, and part of NaOL and DTAB formed co-adsorption on the surface of potassium feldspar to enhance the floatability of potassium feldspar. The XPS and FTIR spectra analysis demonstrated that the cationic collector, DTAB, was first adsorbed on the surface of potassium feldspar through electrostatic attraction in the DTAB/NaOL mixture system. Subsequently, the anionic NaOL collector and cationic DTAB collector form an electron neutralisation complex, thereby resulting in co-adsorption on the surface of potassium feldspar. NaOL was chemically reacted and adsorbed on dolomite surface, but almost no collector was adsorbed on apatite surface. Finally, the adsorption models of different collectors on mineral surface were obtained.
研究领域:
矿物加工工程
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表面化学
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DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
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2014
·Vol. 132
·期 15
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IF 1.64
Pengfei Ma,Zhiping Zhou,Wenming Yang,Bingqing Tang,Hong Liu,Wanzhen Xu,Weihong Huang
Novel, temperature-responsive molecularly imprinted polymers (TMIPs) based on potassium hexatitanate whiskers for selectively adsorbing sulfadiazine (SDZ) from aqueous media were prepared with methacrylic acid (MAA) and 4-vinylpyridine (4-VP) as cofunctional monomers and N -isopropyl acrylamide (NIPAM) as a temperature-responsive monomer. The template–monomer interactions were studied by molecular simulation. In particular, the effects of different kinds of crosslinkers on the selective recognition ability of the TMIPs in water media were investigated. The temperature–responsive adsorption performance and phase behavior of the molecularly imprinted polymers were studied by batch-mode binding experiments, swelling experiments, and contact angle testing. The results demonstrate that the combination of MAA, 4-VP, and NIPAM was a favorable temperature-responsive imprinted system for SDZ in water, and the cocrosslinking agent of ethylene glycol dimethacrylate (EGDMA) and N,N ′-methylene bisacrylamide (MBA) was more suitable compared with either pure EGDMA or MBA. The adsorption kinetics and adsorption isotherms were analyzed by the fitting of different adsorption models. Also, the effect of the temperature on the recovery was investigated by the determination of the spiked SDZ in real-water samples with solid-phase extraction and high-performance liquid chromatography. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132 , 41769.
研究领域:
环境科学
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材料科学
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药物分析
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DOI
高影响因子
CERAMICS INTERNATIONAL
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2021
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IF 4.527
Yifan Du,Bolin Wen,Ronglu Shu,Liping Cao,Wei Wang
In this paper, potassium titanate whiskers was prepared via the Molten salt synthesis on the surface of cordierite ceramics for the regeneration of diesel particulate filters (DPFs). SEM, EDS , XRD , FT-IR, TG-DSC and TPO were carried out to characterize the morphology, microstructure, growth mechanism and catalytic performance of the samples. Potassium titanate whiskers with diameter (100–500 nm) and length (about 3 μm) is tightly combined with the cordierite ceramic substrate . The catalyst performance investigation demonstrates that potassium titanate whiskers decrease the soot combustion temperature apparently. The soot combustion process was studied by thermal analysis tests, and the activation energy of the combustion reaction can be calculated using Freeman-Carroll method. The carbon oxidation activation energy is 14.009 kcal/mol, and the activation energy for the catalytic reaction with potassium titanate whiskers is 6.287 kcal/mol, it can be illustrated that potassium titanate whiskers/cordierite catalyst possess excellence performance for carbon catalytic combustion. The coarseness of the interface increased because potassium titanate whiskers grew on the cordierite substrate, and the trapping ability could improve. This unique microstructure has potential application in the DPF field.
研究领域:
材料科学
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环境工程
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DOI
高影响因子
JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES
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2023
·Vol. 128
·期 24
·e2023JD039971
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IF 4.4
Lanxiadi Chen,Soleil E. Worthy,Wenjun Gu,Allan K. Bertram,Mingjin Tang
Mineral dust is one of the most abundant types of ice nucleating particles in the atmosphere. During atmospheric transport, mineral dust particles can become coated with inorganic and organic solutes, which can impact their ice nucleation activity. Aminium cations formed from amines are one type of organic solute that can coat mineral dust particles in the atmosphere, but their effects on the ice nucleation activity of mineral dust have not been studied. We investigated the effects of primary, secondary, and tertiary aminium cations with methyl and ethyl groups, as well as ammonium cations, on the ice nucleation activity of K-feldspar, an important type of mineral dust, in the immersion freezing mode at low cation concentrations (0.2–20 mM) using a droplet-freezing apparatus. Ammonium cations substantially increased the ice nucleation activity of K-feldspar, consistent with previous studies. In contrast, primary aminium cations significantly reduced K-feldspar ice nucleation activity, and secondary and tertiary aminium cations had no significant effect (the effect was less than the uncertainty of our measurements). Our combined results are consistent with the following mechanisms: ammonium cations undergo ion exchange with K-feldspar, providing exposed N–H groups for hydrogen bonding with ice; primary aminium cations undergo ion exchange with K-feldspar, exposing a hydrophobic tail that is not effective at nucleating ice; secondary and tertiary aminium cations do not undergo ion exchange with K-feldspar due to steric effects caused by the multiple hydrophobic groups on the cation. Key Points Ammonium cations significantly increased the ice nucleation activity of K-feldspar Primary aminium cations substantially reduced the ice nucleation activity of K-feldspar Secondary and tertiary aminium had limited effects on the ice nucleation activity of K-feldspar due to their inability for ion exchange Plain Language Summary Ice nucleating particles are particles in the atmosphere that can initiate the formation of ice in liquid clouds, impacting cloud properties, precipitation, and climate. Mineral dust is a dominant type of ice nucleating particles in the atmosphere. During atmospheric transport, aminium cations, formed from amine gases which can be abundant in the atmosphere, can coat mineral dust particles altering their ability to nucleate ice. However, the effect of aminium cations on the ice nucleation ability of mineral dust particles has not been studied. We investigated the effects of aminium and ammonium cations on the ice nucleation ability of K-feldspar, an important type of mineral dust and ice nucleating particles in the atmosphere. Our results show that secondary and tertiary aminium cations have no effect on the ice nucleating ability of K-feldspar, but primary aminium cations greatly reduce the ice nucleating ability of K-feldspar. This has possible implications for predicting cloud formation in the atmosphere. We also present a mechanism related to ion exchange that can explain our ice nucleation results.
研究领域:
大气科学
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环境化学
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物理化学
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气候学
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DOI
高影响因子
ENVIRONMENTAL TECHNOLOGY
·
2025
·
IF 2
Shizong Wang,Jianlong Wang,Xuan Guo
This study evaluated the uranium removal performance and mechanisms of six minerals: zeolite, montmorillonite, bentonite, phlogopite, sodium bentonite (Na-bentonite), and potassium feldspar (K-feldspar). When the initial uranium concentration was 10 mg/L, montmorillonite exhibited the highest uranium adsorption capacity, reaching 64.9%, followed by bentonite (63.3%), zeolite (57.2%), phlogopite (53.3%), Na-bentonite (37.3%) and K-feldspar (35.7%). The adsorption process was pH-dependent, with bentonite and zeolite showing enhanced adsorption at higher pH levels, while other minerals exhibited complex trends due to changes in uranium speciation and mineral surface properties such as electronegativity. Mechanistic analysis revealed that zeolite, phlogopite and K-feldspar removed uranium mainly through chemical adsorption, such as structural incorporation and surface complexation, whereas montmorillonite, bentonite and Na-bentonite mainly removed uranium via physical adsorption such as ion exchange and electrostatic attraction. Phlogopite exhibited strong uranium retention via interlayer adsorption, whereas Na-bentonite and K-feldspar exhibited weaker adsorption due to lower cation exchange capacity and surface interactions. Thermodynamic studies indicated that adsorption onto montmorillonite, bentonite, zeolite, and phlogopite was spontaneous and exothermic, whereas Na-bentonite and K-feldspar showed endothermic behaviour. Stability tests in bicarbonate solution confirmed phlogopite’s highest uranium retention, whereas bentonite and montmorillonite released more uranium due to bicarbonate complexation. These findings provide insight into uranium adsorption mechanisms and serve as a reference for the selection of materials for radioactive waste disposal repositories.
研究领域:
环境科学
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地球化学
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放射化学
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材料科学
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核废物管理
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）