Autor: Qiu, T. - Prolib Integro

Skocz do pozycji: 1.

Tytuł:: Activating flotation of chalcopyrite using CuSO4 and H2O2 from the cyanide tailings
Autorzy:: Ai, G.
Yan, H.
Qiu, T.
Liu, C.
Tematy:: cyanide tailings
chalcopyrite
CuSO4
H2O2
activation mechanism; Pokaż więcej
Wydawca:: Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Powiązania:: https://bibliotekanauki.pl/articles/109562.pdf Link otwiera się w nowym oknie
Opis:: The effects of CuSO4 and H2O2 on the flotation behavior of cyanide chalcopyrite were investigated by flotation tests, microcalorimetry and X-ray photoelectron spectroscopy (XPS). The underlying activation mechanism was studied in the perspective of micro-thermodynamics and surface properties. The flotation results indicated that cyanide chalcopyrite was strongly inhibited by sodium cyanide, with the maximum flotation recovery of 22.5% only. CuSO4 and H2O2 significantly improved the flotation of cyanide chalcopyrite, and the flotation recovery was increased to 92.28% and 84.35%, respectively. The micro-thermodynamics results indicated that the adsorption heat of butyl xanthate on cyanide chalcopyrite surface increased after the addition of CuSO4 and H2O2, as well as the reaction order. CuSO4 and H2O2 can significantly improve the adsorption of butyl xanthate on the surface of cyanide chalcopyrite by decreasing the apparent activation energy by 80.11% and 66.54%, respectively. XPS analysis indicated that the CuCN was generated on the surface of cyanide chalcopyrite, leading to the loss of sulfur and inhibiting the adsorption of collectors. As a result, the flotation of cyanide chalcopyrite was depressed. It is considered that, CuSO4 and H2O2 can improve the flotation of cyanide chalcopyrite by eleminating CuCN from its surface and increasing the concentration of S by 57.02% and 37.48%, respectively.
Dostawca treści:: Biblioteka Nauki

Artykuł

na półce

Skocz do pozycji: 2.

Tytuł:: Flotation kinetics and thermodynamic behavior of chalcopyrite and pyrite in high alkaline systems
Autorzy:: Yan, H.
Yuan, Q.
Zhou, L.
Qiu, T.
Ai, G.
Tematy:: flotation kinetics
pyrite
chalcopyrite
flotation separation
high alkaline
microcalorimetry; Pokaż więcej
Wydawca:: Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Powiązania:: https://bibliotekanauki.pl/articles/110078.pdf Link otwiera się w nowym oknie
Opis:: The monomineral flotation test and microcalorimetry were used to study the flotation kinetics and thermodynamic behavior of chalcopyrite and pyrite in high alkaline systems of lime and NaOH. The results showed that in these systems there were less hydrophilic substances on the chalcopyrite surface, so that the apparent activation energy of sodium butyl xanthate (SBX) adsorption on chalcopyrite surface was low. This promoted the adsorption of SBX and increased the flotation rate and recovery of chalcopyrite. In contrast, the hydrophilic Fe(OH)3 and SO42- formed by oxidation on the pyrite surface increased the adsorption activation energy of SBX. Thus, the flotation rate and recovery of pyrite were lower. Moreover, in the lime high alkaline system, the hydrophilic calcium film generated on the pyrite surface further hindered the adsorption of SBX, thereby further inhibiting pyrite in this environment. In other words, the lime high alkaline environment increased the apparent activation energy difference of SBX adsorption between chalcopyrite and pyrite compared to the NaOH system, facilitating the flotation separation of chalcopyrite and pyrite. The results can help with the theoretical research of flotation separation of other minerals, and provide guidance for developing low alkaline and lime-free pyrite depressants.
Dostawca treści:: Biblioteka Nauki

Artykuł

na półce

Skocz do pozycji: 3.

Tytuł:: Mental health status of frontline clinical nurses fighting the Omicron variant of COVID-19 – a cross-sectional survey in China
Autorzy:: Li, T.
Qiu, X.
Gong, X.
Zhan, R.
Zheng, X.
Wydawca:: Instytut Medycyny Wsi
Powiązania:: https://bibliotekanauki.pl/articles/28761758.pdf Link otwiera się w nowym oknie
Dostawca treści:: Biblioteka Nauki

Artykuł

na półce

Skocz do pozycji: 4.

Tytuł:: The cross-sectional survey on COVID-19 vaccine hesitancy and it predictors among Chinese parents of 3–17 years aged children in Shenzhen City
Autorzy:: Li, T.
Qiu, X.
Gong, X.
Zhan, R.
Zheng, X.
Wydawca:: Instytut Medycyny Wsi
Powiązania:: https://bibliotekanauki.pl/articles/28761874.pdf Link otwiera się w nowym oknie
Dostawca treści:: Biblioteka Nauki

Artykuł

na półce

Skocz do pozycji: 5.

Tytuł:: Beneficial effects and mechanism of lead ion on wolframite flotation
Autorzy:: Yang, S.
Qiu, X.
Peng, T.
Chang, Z.
Feng, Q.
Zhong, C.
Tematy:: activator
wolframite
lead ion
benzohydroxamic acid
flotation; Pokaż więcej
Wydawca:: Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Powiązania:: https://bibliotekanauki.pl/articles/109484.pdf Link otwiera się w nowym oknie
Opis:: In this study the effects and mechanism of lead ions influence on wolframite flotation with benzohydroxamic acid (BHA) were studied through micro-flotation, adsorption experiments, zeta potential measurements, logarithmic concentration diagram, and X-ray photoelectron spectroscopy. It was observed that lead ions could significantly enhance the recovery of wolframite in flotation and adsorption density of collector BHA onto the wolframite surface. The results showed that Pb existed in the forms of lead ion, monohydric lead, and lead hydroxide at the water-wolframite interface respectively, at three pH ranges. They increased the zeta potential of wolframite. However, the zeta potential of wolframite was still negative, resulting in repulsive electrostatic force to anionic collector BHA. Combining with XPS spectra, it revealed the chemisorption of BHA onto the wolframite surface. In addition, PbO or Pb(OH)2 was observed on the wolframite surface due to the reaction between lead ions and wolframite. These reaction products increased the adsorption site of BHA on the wolframite surface because Pb-hydroxamate was found on the wolframite surface.
Dostawca treści:: Biblioteka Nauki