Informacja

Drogi użytkowniku, aplikacja do prawidłowego działania wymaga obsługi JavaScript. Proszę włącz obsługę JavaScript w Twojej przeglądarce.

Wyszukujesz frazę "Chen, R." wg kryterium: Autor


Wyświetlanie 1-4 z 4
Tytuł:
Flotation separation of scheelite from calcite using sodium polyacrylate as depressant
Autorzy:
Zhang, Y.
Chen, R.
Li, Y.
Wang, Y.
Luo, X.
Powiązania:
https://bibliotekanauki.pl/articles/110896.pdf
Data publikacji:
2018
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
scheelite
calcite
flotation
sodium polyacrylate
selective depression
Opis:
The depressing properties of sodium polyacrylate (PA-Na) for calcite from scheelite were studied by microflotation experiments, zeta potentials, X-ray photoelectron spectroscopy (XPS) and density functional theory (DFT) calculation. Flotation results revealed that the selective depression effect of PA-Na was better than that of sodium silicate (Na2SiO3), and PA-Na can depress calcite more effectively than scheelite. The flotation recovery of scheelite and calcite kept at about 75% and 15% respectively at the pulp pH 9.3~9.6 and PA-Na concentration from 37.5 mg/dm3 to 50 mg/dm3. The zeta potentials of the minerals were significantly altered and the zeta potential of calcite became more negative than scheelite. XPS analysis deduced the occurrence of chemisorption between PA-Na and mineral surfaces, and the chemisorption of PA-Na on calcite was stronger than on scheelite. The results from DFT calculation demonstrated that the absolute value of the adsorption energy in the presence of PA-Na on the surface of calcite {104} was larger than on the surface of scheelite {111}. With the combination of the analysis, it could be concluded that calcite was more easily depressed than scheelite, and this finding remarkably matched with the microflotation experimental results. Furthermore, by using PA-Na as depressant, the flotation separation of scheelite from calcite can be achieved by controlling the flotation pH and PA-Na dosage.
Źródło:
Physicochemical Problems of Mineral Processing; 2018, 54, 2; 505-516
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Mass transfer process of leaching weathered crust elution-deposited rare earth ore with magnesium salts
Autorzy:
Chen, Z.
Zhang, Z.
He, Z.
Chi, R.
Powiązania:
https://bibliotekanauki.pl/articles/110343.pdf
Data publikacji:
2018
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
mass transfer
magnesium salts
theory plate
weathered crust elution-deposited rare earth ore
Opis:
In order to optimize the leaching process of weathered crust elution-deposited rare earth ore with magnesium salts, the influence of different flow rate, concentration of magnesium ions, initial pH of magnesium salts solution and experimental temperature on the mass transfer process of rare earth and aluminum was investigated in the case of using magnesium salts as leaching agent. The relationship between the flow rate μ and the HETP (Height Equivalent of Theoretical Plate) is in accordance with the Van Deemter equation when magnesium salts were used as leaching agent. The optimum condition for rare earth and aluminum were 0.4 cm3/min of flow rate and 0.2 mol/dm3 of magnesium ion concentration of magnesium sulfate, magnesium chloride and magnesium nitrate respectively. Under this condition the mass transfer efficiency of rare earth and aluminum with three kinds of magnesium salts follow the order of Mg(NO3)2>Mg(Cl)2>MgSO4. High temperature contributes to improving the mass transfer efficiency of rare earth and aluminum. Magnesium nitrate as the leaching agent can get the highest leaching mass transfer efficiency of rare earth and magnesium sulfate as the leaching agent can make the impurity leaching and mass transfer efficiency of Al is the lowest.
Źródło:
Physicochemical Problems of Mineral Processing; 2018, 54, 3; 1004-1013
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Preparation of activated bentonite and its adsorption behavior on oil-soluble green pigment
Autorzy:
Zheng, R.
Gao, H.
Ren, Z.
Cen, D.
Chen, Z.
Powiązania:
https://bibliotekanauki.pl/articles/110655.pdf
Data publikacji:
2017
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
activated bentonite
acid activation
microwave heating
oil-soluble green pigment
adsorption
Opis:
The present research work focuses on effective preparation of activated bentonite (AB) and its application in removal of oil-soluble green pigment (OSGP) from either vegetable oils or food-processing wastewater. Mono-factor experiments were carried out to explore the effects of operation factors in preparation of AB. The parameters investigated were the effect of contact time, adsorbent dosage, initial OSGP concentration and temperature. The chemical composition, crystalline phases, microstructure and functional groups of prepared AB were characterized and evaluated by X-ray fluorescence (XRF), X-ray diffraction (XRD), scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FT-IR), respectively. The adsorption kinetics and equilibrium isotherms were studied, finding that the adsorption process fitted better with the pseudo-second-order model and the Freundlich isotherm equation. In addition, thermodynamic parameters, such as standard the Gibbs free energy (ΔG°), standard enthalpy (ΔH°) and standard entropy (ΔS°) were also calculated, indicating that adsorption was spontaneous and endothermic. The findings of this investigation suggest that AB prepared through microwave activation as a cheap adsorbent holds great potential to remove oil-soluble green pigment in the wastewater treatment process.
Źródło:
Physicochemical Problems of Mineral Processing; 2017, 53, 2; 829-845
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of modified starch on separation of fluorite from barite using sodium oleate
Autorzy:
Chen, Z.
Ren, Z.
Gao, H.
Qian, Y.
Zheng, R.
Powiązania:
https://bibliotekanauki.pl/articles/109938.pdf
Data publikacji:
2018
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
fluorite
barite
modified starch
flotation
Opis:
In this study, a modified starch was utilized to selectively separate barite from fluorite. The results of flotation tests showed that highly selective separation of fluorite from barite was obtained when 250 mg/dm3 of modified starch and 13.16×10−5 mol/dm3 sodium oleate was used in neutral solutions. FTIR spectra results showed that the modified starch can adsorb on the fluorite and barite surfaces. Zeta potential analyses indicated that the modified starch had little effect on adsorption of sodium oleate on the fluorite surface, although it interfered with the adsorption of sodium oleate on the barite surface. Contact angle measurements results corresponded well with the flotation results.
Źródło:
Physicochemical Problems of Mineral Processing; 2018, 54, 2; 228-237
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
    Wyświetlanie 1-4 z 4

    Ta witryna wykorzystuje pliki cookies do przechowywania informacji na Twoim komputerze. Pliki cookies stosujemy w celu świadczenia usług na najwyższym poziomie, w tym w sposób dostosowany do indywidualnych potrzeb. Korzystanie z witryny bez zmiany ustawień dotyczących cookies oznacza, że będą one zamieszczane w Twoim komputerze. W każdym momencie możesz dokonać zmiany ustawień dotyczących cookies