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| 11. |
EXCHANGE MECHANISMS OP SILVER ON NICKEL AND ZINC PERROCYANIDES |
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Solvent Extraction and Ion Exchange,
Volume 5,
Issue 4,
1987,
Page 757-780
C. Loos-NesXovic,
M. Pedoroff,
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PDF (339KB)
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摘要:
The retention mechanisms of silver ions were studied on some nickel and zinc ferrocyanides Which represent several types of structures. This was performed through the study of the influence of the ferrocyanide composition and structure, a determination of the kinetics and capacity, a study of the modification of the solid at each step of the fixation. All the studied ferrocyanides are able of removing silver from aqueous solutions with a high efficiency. The kinetics is always very fast. It could be interpreted by an intracrystalline diffusion for acid-nickel ferrocyanide, but was too fast for Interpretation in other cases. The main feature is a substitution of all ferrocyanide cations leading to a composition tending to Ag4Fe(CN)6. However, the stability of this compound is questionable. The capacity of fixation exceeds the predicted value and may reach 6 silver atoms per iron atom in the initial product. A possible interpretation is the formation of silver cyanide. The fixation is a complex phenomenon involving structural changes in the crystal lattice.
ISSN:0736-6299
DOI:10.1080/07366298708918592
出版商:Taylor & Francis Group
年代:1987
数据来源: Taylor
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| 12. |
NEW STRATEGIES IN SEPARATION OF CLOSE BOILING(SOLID)MIXTURES : EXTRACTION INTO MICELLAR AND MICROEMULSION MEDIA |
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Solvent Extraction and Ion Exchange,
Volume 5,
Issue 4,
1987,
Page 781-788
A. Mahapatra,
M. M. Sharma,
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PDF (110KB)
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摘要:
Aqueous solutions of various surfactants, such as, sodium lauryl sulphate, lauryl alcohol-7-ethoxylate, cetyl pyridinium chloride, cetyl trimethylammonium bromide, etc., at concentrations above their critical micelle concentration values, known as micellar solutions, and microemulsion solutions consisting of these surfactants and a co-surfactant,n-butanol, have been used successfully to separate mixtures of isomeric/non-isomeric close boiling substances likeo-nitrochlorobenzene/p-nitrochlorobenzene,o-nitrotochlorbenzene,p-nitrotoluene, 2,6-xylenol/p-cresol, -2,4-dichloro-phenol/2,4,6-trichlorophenol,o-isopropylphenol/p-isopropylphenol, from their solid mixtures. Exceptionally high values for the separation factor have been realized and these novel methods appear to be promising for industrial utilization.
ISSN:0736-6299
DOI:10.1080/07366298708918593
出版商:Taylor & Francis Group
年代:1987
数据来源: Taylor
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