76-19-7Relevant articles and documents
Thermodynamically unstable fluorides of nickel: NiF4 and NiF3 syntheses and some properties
?emva,Lutar,Chacón,Fele-Beuermann,Allman,Shen,Bartlett
, p. 10025 - 10034 (1995)
F- acceptors (BF3, AsF5, SbF5, or BiF5) added to solutions of NiF62- salts in anhydrous hydrogen fluoride (aHF) below -65 °C precipitate the tan solid NiF4. This solid, preserved at ≤-65 °C, is quantitatively converted, by 2 equiv of F- donor (XeF6 or KF) in aHF, to dissolved NiF62-. Dry NiF4 loses F2 above -60 °C, the decomposition to nearly black NiF3 becoming rapid at ~0 °C. When the dry NiF4 is prepared from K2NiF6, inclusion of some K+ leads, on thermolysis at 0 °C, to a pyrochlore form of NiF3 (P-NiF3). P-NiF3 contains K+ in the open channels, with KxMiF3, x ≈ 0.1. The nearly cubic P-NiF3 unit cell is rhombohedral: a0 = 9.933(3) A?, α = 91.01(3)°, V = 980 A?3, z = 16, with absent reflections coincident with those of the cubic space group Oh7-Fd3m, appropriate for pyrochlore. Decomposition of NiF4 in aHF begins at -65 °C and is rapid at 0 °C, giving black rhombohedral NiF3 (A-NiF3) with a0 = 5.168(2) A?, α = 55.46(3) A°, V = 87.3 A?3, z = 2. When the NiF4 is made and decomposed at ~20 °C, with K+ present, a hexagonal tungsten bronze form of NiF3 is precipated (H-NiF3), with a0 = 7.074(6) A?, c0 = 7.193(6) A?, V = 312A?3, z = 6. R- and H-NiF3 can also be made by mixing solutions of Ni2+ salts [e.g., Ni(AsF6)2] with NiF62- salts (e.g. K2NiF6) in aHF. All forms of the trifluoride (R, H, and P) lose F2 on warming (R > 39°, H > 72° and P > 138 °C) to yield NiF2, but an intermediate red-brown phase is observed for R-NiF3. R-NiF3 at ~20 °C, oxidizes Xe to Xe(VI), perfluoropropene, C3F6, to perfluoropropane, C3F8, and solid LiCl with incandescence. H-NiF3 and P-NiF3 interact similarly but less energetically.
Method for performing olefin addition reaction by using microchannel reactor
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Paragraph 0060; 0061; 0062; 0063; 0064, (2017/03/14)
The present invention discloses a method for carrying out addition on olefin and fluorine gas by using a microchannel reactor, wherein C2-C9 olefin or fluoroolefin reacts with F2 in a microchannel reaction module to obtain the corresponding fluoroalkane. According to the present invention, with the method, the purity of the prepared fluoroalkane is high, and the method has the cost advantage.
Catalytic pyrolysis of CHF3 over activated carbon and activated carbon supported potassium catalyst
Han, Wenfeng,Kennedy, Eric M.,Liu, Huazhang,Li, Ying,Adesina, Adesoji A.,MacKie, John C.,Dlugogorski, Bogdan Z.
scheme or table, p. 698 - 703 (2010/09/12)
The catalytic activity of activated carbon (AC) and activated carbon supported potassium for the decomposition of CHF3 was investigated at temperatures between 873 and 1173 K and at a space velocity of 4300 h -1. It is found that activated carbon supported potassium shows high and relatively stable activity during the pyrolysis of CHF3 under the conditions studied. Compared with the gas phase reaction, the conversion of CHF3 increases by up to 10 times between 873 and 1123 K, with the major products being C2F4 and C3F6. Selectivities as high as 55% to C2F4 and 35% to C 3F6 are achieved under optimum conditions. The main byproduct HF readily reacts with K2O in the catalyst, converting the catalyst from K2O/AC into KF/AC. Selectivity to the major products remains relatively constant following this transformation.