secondary cells with lithium anodes and immobilized fused_salt

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. .- . - ..... . . I ,caving the reactor, T is the average residence time in the reactor, and n is the orOer of the reaction.' 6 plot of ab-cy) vs T, where a is the fraction reacted, should be linear with a 80. It can be shown from eq 2 that for a first-order reaction, slope equal to the rate constant. Figure 1 shows that the decomposition of ClF5 follows first-order kinetics up to 80$ reaction at 293O. "he data in Figure 1 were c'stained at temgeratures of 29l.5-294.Oo, md corrected to 293.0' using an activation energy of 41 kcal/mole. The rate constant, 1x1 from each experiment is listed In Table 1. The best first-order rate constant, klA, at each temperature, obtained fro3 a ?lot of the type shown in Figure 1, is given in the last colm of Table 1 ad plotted in the Arrhenius fonn in Figure 2. A least squares fit of the data to the Arrhenius expression yields the line shown in Figure 2 which represents the rate expression: -1 kl = exp(-41,330/RT) sec (3) :.e mceytainty in activation energy is about 2 kcal./mole. n; -,e ~Lxing requirements for a stirred flow reactor do not allow a convenient 3roce5ure for varying widely the surface-to-volume ratio, but the high values of the activation enera and preexponential factor suggest that the reaction is hao- geneous in nature. reactor, containing products of reaction, had been allowed to sit at 280° for 1 Lonth . 21scuss10s Three possible mechanisms may be written which are compatible with the observed rate expression, i.e., first order in ClF5 with no apparent inhibition as the products accwulate : A) Unimolecular Elimination of F2 ClF5 4 CLF3 + F2 B) Non Chain Radical Mechanism CLr5 0 CLF4 + F C1F4 0 ClF3 + F F + F + M -. F2 + M C) Long Chain Radical Mechanism ChF5 - clP4 + F F + Clr 5 -. ClF4 + F2 CL"4 0 ClF3 + F F + ClF4 0 CLF3 + F2 Also, it was found that the rates were unchanged after the "he long chain mechanism (C) may be questioned on the bagis of the observed rate parameters A and Z. Mechanism (C) requires that 1 A = (!*)+ and E P &(E5 + E6 + ET - E$ ?he A factors for the 1-dividp steps can be estimated fran the generalizations yoposed by Benson aad Demore . nus, 0. S. W. 3,enson anC Y. 3. Sezore, Ann. Rev. Phys. Chem., 16,426 (1965).
dasel-ved vdxe of 7 9 are assunecl equd to + E-7, where AHo is the heat of reaction for Cg; C1F3 + 2r" (&Yo = 57 KCal/mole) IS t'ce nczivstion energy for the reverse of reection (7). Semenov's ai. gives 9-7 = 2.5 :(Cal/xole and 36 = 11.0 KCal/n;ole. The raciical-rGdic& xactlons (-5) =&(a)' are assmeri to have zero activetion energies. Therefore Z = i(57.0 + 2.5 + 11.0-0)- 35 KCal/aole. This value is somewhat lower thm the GbserveL value of h.3 KCal/nole and suggests thzt the long chain mechanism (C) +obaiLy is zot inportant in the decomposition of CWs. -.. c _ u.7;'ortmztely the data do not allow e choice to be nade between the molecular illmination mechanis-3 (A) za8 the non chain mechanism (B). Thermochemical data give Keq = 10 -~.a5~;+ for the reverse of reaction (4). Therefore, U = + 105-8 e-(-22,&0/i~) liter/mole sec. r.ot unreasonable for a bkolecular reaction. reaction (A) camot be eliminated. The A factor 105-8 liter/nole sec is fience, the nolecular elimination If the non chain radical mech&nisn (B) is correct, then the measured activation energy, h0.3 XCal/mole, is equal to the bond dissociation energy for the first C1-F bond in C1? Tnis value seems reasonable since the average bond enerfg in ClF5 is j6 i~al/~Oie5'5. Further support for the non chain radical mechanism is given by the generalization of Benson and DeNore6 that the A factor f uninoleculy reactions involving the splitting off of atms are in the range of 10' to 1015sec- . It now remains to discuss the recent photochemical investigation by Krieger et 2 a l e They studieC tne kinetics of the photochemical formation of ClF5 from clF3 ana T2 (365 su, 16-70') an8 obtained the complex rate expression: , 5eir sonewhat unllsual nechanisn involves the formation of an activated ClF5 molecule which can (1) be collisionally ceactivzted to CW5, (2) react directly with C1F3 to ,Corn 2 CF4 raLicals, or (3) +it into CU4 + F. In order to explain their observed results (quantum yield aependent on inert gas pressure and on ClF3 pressure), all *- "r-ee 1 of these processes nust occur to an appreciable extent in each of their experlzents. PI,. L..cse pLotochezica1 results indicate that the CP5 activatec? nolecule decomposes r.oze rapi~f thazz classical theory would predict. Also, the thermal decomposition of CL75 stould be press'ure ciependent and accelerated by the presence of the product CLT2. ,7- -..e tkezzial &:.d -,hotoche-;lical resfits can be shown to be compatible in two ways. -._.".A i.. caz bc calculated from the photochemical rate constaqts that the accele.-3*-.- - effect 0:' Cll3 woiia not be sufficient to appreciably affect the first-order plot shoi.3 In Fig. 1. Therclal experiments would have to be run with added CLF3 and at various total pressures to determine if the decomposition is dependent on the . . I - .- . 7. :;. :;. Sc~anov, "Sozle Iro3iess in Chemical Kinetics ana Reactivity," Volune I, princeton University ?res, Princeton, New Jersey, 1958, P 29. "li Y.
Page 1 and 2:
Introduction 1. SECONDARY CELLS WIT
Page 3 and 4:
I time curves at constant current d
Page 5 and 6:
I 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11
Page 7 and 8:
7. IV IV- Equivalent Weight, gr/ Eq
Page 9 and 10:
1 3 9 SOYO FILLER,HQT PRESS Fig. 4.
Page 11 and 12:
11. COAL PYROLYSIS USING LASER IRRA
Page 13 and 14:
13. Macerals. Macerals from a singl
Page 15 and 16:
i 1 I Photochemistry. A fundamental
Page 17 and 18:
t P li. al ’ i ._ m LL
Page 19 and 20:
' 19. PYROLYSIS OF COAL IN A MICROW
Page 21 and 22:
I 21. In the third stage, the gas e
Page 23 and 24:
.4 4 0 W 0 m .d m x .-( 0 x w M m s
Page 25 and 26:
' 25. CONCLUSIONS The principal rea
Page 28 and 29:
' .4 b s tract 28.
Page 30 and 31: 30. the course of the experiment Ex
Page 32 and 33: d (Sulfur] dt m i trogenj dt 32. E
Page 34 and 35: 34. Table 1, Properties of Feed Mat
Page 36 and 37: 0 0 0 m 0 VI b N 0 c, VI N 0 v, N h
Page 38 and 39: - Literature Cited 38 1. Gordon, K
Page 40 and 41: 40 z - B 30 w 6 20 yl w U 10 40. 10
Page 42 and 43: Z 0 In 80 CK W > 6 60- 0 I- 40- Z W
Page 44 and 45: 44. 2.0 I 1.2 - 0 2 1.0- 0.8 i TIME
Page 46 and 47: - 2.81 1.NITROGEN 2. SULFUR 3. GASO
Page 48 and 49: 48. The oil from the separator is v
Page 50 and 51: . 50 . Table I . Properties of Pitc
Page 52 and 53: 52. Coke yield A - - - - 0 800 900
Page 54 and 55: FIGURE 8. 54. t 0.5 1 800 900 1,000
Page 56 and 57: Introduction 56. FLUORODINITROETUNO
Page 58 and 59: chloride extractant without other h
Page 60 and 61: 60. identified (Reference 7) as the
Page 62 and 63: 62. to FEFO -e quite high (80 to 85
Page 64 and 65: 64. RECENT CHEMISTRY OF THE OXYGEN
Page 66 and 67: polymers for the conventional fuel
Page 68 and 69: 68. In summary, two general methods
Page 70 and 71: 70. Table XI1 Differential Thermal
Page 72 and 73: vapor Pressure (psia) Figure 4. Vap
Page 74 and 75: C H -0-C-NHF, - 2 5 II 0 74. H 9304
Page 76 and 77: 76. The infrared spectrum is descri
Page 78 and 79: , 78. PREPARATION AND POLYMERIZATIO
Page 82 and 83: If it ~ 3 ~ o~t 7 s Y'2t the therm1
Page 84 and 85: Chlorine Fentafluaride T q D OC 252
Page 86 and 87: , 86. Zeections of Cl30 and AsF5. M
Page 88 and 89: aa . - The rrost difficult rctionel
Page 90 and 91: 90. DENSITY, VISCOSITY AND SURFACE
Page 92 and 93: 92. If it is assumed that the syste
Page 94 and 95: 94. After condensation of oxidizer
Page 96 and 97: Stirring Solenoid LHe 7. Cryostat 9
Page 98 and 99: Introduction 98. RFACTIONS OF OxYcm
Page 100 and 101: , Acknowledgement 100. This work wa
Page 102 and 103: 102. volume and then by pumping to
Page 104 and 105: 104. The x-ray powder pattern (Tabl
Page 106 and 107: Irredie tion Time, mi&) 106. Table
Page 108 and 109: I. Introduction 108. RE7IIEw OF ADV
Page 110 and 111: 1.40 w F O/) 103-4O 'F 110. /H 0 21
Page 112 and 113: !P, "c -- -2118.5 -195 -172 -16.1 .
Page 114 and 115: 114. weaker than those in NF02. The
Page 116 and 117: Compound C102F ~ 1 , 0 ~ -146 ~ 116
Page 118 and 119: 118. fom such salts as cS+m8- have
Page 120 and 121: 120. DETONABILITY TESTING AT NONAMB
Page 122 and 123: I 122. top) is closed with caps whi
Page 124 and 125: 124. five pieces of MDF, each 20.00
Page 126 and 127: 126. auxiliary equipment. For conve
Page 128 and 129: 128. reliability. Details of most o
Page 130 and 131:
130. The time required for the deto
Page 132 and 133:
132. Fig. 2 Typical Witness Plate
Page 134 and 135:
I ll 134. L, ALUMINUM 011+ ‘7 I-
Page 136:
W (3 3 a (3 W m 3 0 v) W E k- / W 3
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