Informacja

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

Wyszukujesz frazę "Xie, S." wg kryterium: Wszystkie pola


Wyświetlanie 1-5 z 5
Tytuł:
Adsorption behavior of surfactants on lignite particles with different densities in aqueous medium
Autorzy:
Wang, J.
He, Y.
Wen, B.
Ling, X.
Xie, W.
Wang, S.
Powiązania:
https://bibliotekanauki.pl/articles/110538.pdf
Data publikacji:
2017
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
interfacial surface free energy
adsorption
lignite
surfactant
Washburn equation
Opis:
Lignite is well known for its strong hydrophilicity and hard-to-float properties. However, the surface free energy of the solid is made up of two components, that is the Lifshitz-van der Waals and acid-base interaction energy. Differences in these two components between the low ash (lower density) and high ash fraction (higher density) provide a benefit for improving the separation efficiency through introducing surfactants in flotation. In this paper, thermodynamic characterization of three density lignite fractions was measured by a Washburn dynamic method. Combining the Washburn equation and Van Oss-Chaudhury-Good theory, the surface free energy components of three samples were calculated according to the wetting process by n-hexane, diiodomethane, deionized water and ethylene glycol. The Lifshitz-van der Waals part of surface free energy reduced with the coal density increase, especially between fractions of -1.45 g/cm3 and 1.45-1.80 g/cm3, while the Lewis base part increased slightly. The interfacial interaction free energies between the surfactant and lignite in aqueous medium indicated that the low hydrophilic index benefited for the stronger adsorption intensity. Increase of the surfactant Lifshitz-van der Waals component increases the adsorptive intensity on lower density lignite and the repulsive intensity on higher density lignite, which is beneficial for separation.
Źródło:
Physicochemical Problems of Mineral Processing; 2017, 53, 2; 996-1008
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Relationship between flotation and Fe/Mn ratio of wolframite with benzohydroxamic acid and sodium oleate as collectors
Autorzy:
Yang, S.
Feng, Q.
Qiu, X.
Gao, Y.
Xie, Z.
Powiązania:
https://bibliotekanauki.pl/articles/109666.pdf
Data publikacji:
2014
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
wolframite
flotation
collector mixture
benzohydroxamic acid
sodium oleate
Opis:
Several studies revealed that flotation of wolframite changes with different Fe/Mn ratios, but they did not reach a consensus. This relationship in the presence of benzohydroxamic acid (BHA) and sodium oleate (NaOl) as collectors was studied in this paper through comparison of probability distribution curve of wolframite with different Fe/Mn ratios between the raw ore and the flotation concentrate, the pure mineral flotation and solution chemistry of flotation. The results showed that wolframite with high Fe/Mn ratio showed higher flotation with BHA as a collector while the flotation behavior of wolframite was completely opposite with NaOl as a collector. Besides, the calculations of chemical equilibrium in the solution were plotted as ΔG°-pH graphs. The results revealed that the flotation of wolframite may be determined by the interaction between BHA and ferric(II) ion or between NaOl and manganous ion. From the perspective of collector mixture, the results also explain the high collecting capability of the BHA/NaOl collector mixture, which can be defined as “functional complementation”.
Źródło:
Physicochemical Problems of Mineral Processing; 2014, 50, 2; 747-758
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Ammonium chloride’s weakening effect on the copper activation of pyrite in flotation and the surface regulation mechanism behind it
Autorzy:
Zhang, Shengdong
Chen, Yumeng
Tong, Xiong
Xie, Xian
Lu, Yalin
Powiązania:
https://bibliotekanauki.pl/articles/110323.pdf
Data publikacji:
2019
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
pyrite
depression
cuprammonium solution
pH buffering property
flotation
Opis:
The traditional separation process of pyrite and marmatite is carried out under highly alkaline conditions. Therefore, a large amount of lime is demanded and the zinc recovery cannot be guaranteed. However, under weakly alkaline conditions, copper-activated pyrite has good floatability, which is difficult to separate from marmatite. In this paper, ammonium chloride (NH4Cl) is used for depressing the flotation of copper-activated pyrite to achieve the separation of these two minerals under weakly alkaline environment. The flotation tests show that NH4Cl can significantly reduce the floatability of pyrite in weakly alkaline conditions. The results of adsorption tests and X-ray photoelectron spectroscopy (XPS) analyses indicate that NH4Cl can obviously change the composition of pyrite surface by increasing the content of iron/copper hydroxide and reducing the content of copper sulfides. Calculation of the solution composition demonstrates that the addition of NH4Cl results in the occurrence of Cu(NH3)n2+ and the pH buffering property. Based on these results, it can be concluded that the depression of NH4Cl on copper activated pyrite is mainly derived from two aspects: 1) the pH buffering property of the conjugated acid-base pair (NH4+/NH3) can impede the decline of OH- concentration, which results in more hydroxide adsorbed on pyrite; 2) NH3 (aq) competes with the pyrite surface to consume Cu2+through complexation, which causes a reduction in the amount of copper sulfides formed on the pyrite surface.
Źródło:
Physicochemical Problems of Mineral Processing; 2019, 55, 5; 1070-1081
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Response of energy-size reduction to the control of circulating load in vertical spindle pulverizer
Autorzy:
Li, H.
He, Y.
Zhang, Y.
Ge, Z.
Xie, W.
Wang, S.
Li, K.
Powiązania:
https://bibliotekanauki.pl/articles/110803.pdf
Data publikacji:
2017
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
circulating load control
response of energy-size reduction
mixture grinding
energy efficiency
Opis:
In the vertical spindle pulverizer (VSP), the large circulation ratio and high ash and sulfur contents in circulating load would result in intensive energy consumption and low grinding efficiency. Although the control of circulating load would help increase the energy efficiency, no quantitative study has been conducted due to the high temperature and pressure in the closed VSP. In this study, response of energy-size reduction to the control of circulating load was studied by the experimental simulation method. Coal mixtures with fine/coarse ratio of 11:1, 8:1 and 6:1 were ground by a lab-scale roller mill. Energy-size reductions of the coarse coal were compared to evaluate the influence of circulating load control. Results showed that the product with the coarse coal increased by 30% when the specific breakage energy was 1.0 kWht–1 as the circulation ratio decreased from 11 to 6. Meanwhile, a breakage characteristic index of the coarse coal was two times higher due to the cushioning effect of fines. Besides, decrease of circulation ratio led to increase of the breakage rate of coarse coal, and the energy saving improved by 57%. With the same energy input of 2.0 kWht-1, the yield of –0.09 mm pulverized fuel (PF) increased from 22 to 43%. Therefore, controlling the circulating load is an effective method to improve the breakage rate of coarse coal and energy efficiency for PF generation.
Źródło:
Physicochemical Problems of Mineral Processing; 2017, 53, 2; 793-801
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Trace muscovite dissolution separation from vein quartz by elevated temperature and pressure acid leaching using sulphuric acid and ammonia chloride solutions
Autorzy:
Lin, M.
Pei, Z.-Y.
Lei, S.-M.
Liu, Y.-Y.
Xia, Z.-J.
Xie, F.-X.
Powiązania:
https://bibliotekanauki.pl/articles/110755.pdf
Data publikacji:
2018
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
vein quartz
muscovite
sulphuric acid
ammonium chloride
acid leaching
Opis:
Effects of sulphuric acid and ammonia chloride on muscovite dissolution were studied in acid leaching of vein quartz under elevated temperature and pressure. The leaching processes have been studied in detail by analyzing sources of impurity minerals, optimizing leaching process, analyzing leaching kinetics of Al in muscovite and charactering leaching mechanism of muscovite. The results showed that elements of Al and K mainly occurred in muscovite, and 98.10% or more of muscovite could be removed by acid leaching, while the process had limited influence on the particle size of quartz sand. Leaching of Al in the quartz ore was mainly controlled by chemical reaction. A calcination process and ammonia chloride were used for reducing chemical reaction resistance by damaging crystal structure of muscovite and providing stable acid leaching environment. Combined with the calcination process, muscovite, as a main gangue mineral, was effectively extracted during acid leaching of vein quartz at elevated temperature and pressure.
Źródło:
Physicochemical Problems of Mineral Processing; 2018, 54, 2; 448-458
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
    Wyświetlanie 1-5 z 5

    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