secondary cells with lithium anodes and immobilized fused_salt
secondary cells with lithium anodes and immobilized fused_salt secondary cells with lithium anodes and immobilized fused_salt
polymers for the conventional fuel can be seen. Use of a carboxy-termhated polyester based on diethylene aycol and sdipic acid, with an owen content of 37.odp results in almost a 50$ reduction in solid carbon in the exhaust. The required mount of IfH4ClO1 oxidizer for a 220OoF temperature is reduced to approximately 66. For a 42.d$ oxygen content binder, the wunt of oxidizer for generation of 2200°F is reduced still further, to approximately 58%. Since one of the combustion products resultingfromthe use of NH4ClO4 is Ha, with its consequent erosivity of certain metals of construction, these reductions in oxidizer content are quite desirable, since they result in corresponding reductions in HCl content. The second nethod of lowering flame temperature involves the addition of a third component to tie system that is as low in energy content as possible and that has a? internal oxidation ratio close to 1.0. Compounds with these high ' negative heats of formation and balanced stoichiometry are aptly designated as 66. "coolants", since they are both poor fuels and poor oxidizers. A representative l'ist of compounds of this type is shown in Table 11. The oxidizers, ammonium perchlorate and ammonium nitrate, are included for comparison. For each compound, the empirical formula, density, oxidation ratio, and heat of fomtion in kilocalories per gram are given. Because warm gas generating systems mt be efficiently packaged, high density values axe desirable. The advantGe of possessing an oxidation ratio close to 1.0 has already been pointed out. Finally, since high flame temperatures result from either low negative or positive heat:' of formation, it is desirable that the value for &/M be as large a negative nunber as possible, in order to produce low flame temperatures. Exanination of tie compounds in Table II shows materials ranging from low oxidation ratio fuel-like compounds such as oxamide and azodicarbonanide, to more evenly bilxced materials such as armnonium oxalate hydrate, oxalohydroxamic acid, and hydroxylamonium oxalate. Ammonium dihydrogen phosphate theoretically appears to be zr~ osidizcr, like arsnoniurn nitrate, and ammonium perchlorate; however, in actaity it serves only as a coolant, since the phosphate portion of the molecule is extrenely stable at elevated temperatures, and is not a source of oxygen, unlike the nitrate and perchlorate structures. As might be expected, the compounds in the middle of the list are the most desirable end useful corlants; in particular, oxalohydroxamic acid (also sometimes referred to as dihydroxyglyoxime-DHG) is of particular interest. Its high density, bzlanced stoichiometry and negative heat of formation are of importance, in this regard. Table I11 points out still another important factor in the selection of an effective coolant.. A good coolant is thermally stable, but not too stable. 0xalohydrom.nic acid is quite satisfactory in this respect, sharing no endotherm or exotherm in differential thermal analysis below 300°F, but it completely fumes off at the slightly higher temperature of 338OF (dec.). Its arrrmonium salt, on the other hand, exhibits its first exotherm at a lower temperature than 30O0F, but it is not completely decomposed until 400°F is reached. The other coolants shown are mre stable in e thermal sense, but this fYequently means that the amounts that can be added to a propellant formulation are limited to low levels because of difficulty in achieving combustion. The effect of adding various aJmunts of coolant to typical warm gas generator propellant compositions is shown in Figure 2. At the same binder content of 26.58, larger amounts of oxalohydroxamic acid (DEG) are required to reduce the flame temperature of the 4% oxygen content binder to the 2200'F level then far the 3'7% oxygen content binder. !&e mre negative heat of formation of hydroxylanrmonium oxalate makes it possible to reach the 22000F level with even less coolant. The
! overall effectiveness of these coolants is realized when the flame temperatures of the same compositions without coolant are compared, for these are 4250°F and 39OOor', respectively, for the 42$ and 37dp oxygen binders. Hydroq4ammonium oxdate (HAO) is especiay effective in improving the cleanliness of the exhaust for only 22$ of this coolant produces a 2278'F flame temperature with no solid carbon in the ex!aust products. In eddition to the foregoing methods of reducing carbon in the exhaust products, it is also possible to effect a reduction by reducing the pressure at vhich the combustion reaction is carried out. An indicatior! of the extent of this Pactor can be seen in Figure 3, where the weight percent of solid carbon formed in tie Exhaust is plotted as a function of the combustion pressure for a single composition over the pressure range of 100 psia to 20,000 psia. At 20,000 psia, tile carbon content of the exhaust is over 5% by weight, while at pressures below 500 psia, C$ carbon results. A reduction in flme temperature also results, xiti the vdue of 2374OP for the 20,000 psia level decreasing to 2058OP at 100 psia. 67. In nddition to the formation of solid carbon, it is &so possible for mnium chloride to condense in solid crystaline particles during the reduction of flame temperature resultin& from expansion of the combustion gases through a nozzle or turbine system. 'ine presence of chlorine in the ammonium perchlorate leads to the formtion of HC1 as one of the combustion products; this in turn reacts with traces of IJH3 in the coqosition products to form iQCl when the temperature or the system falls below the value at which the vapor pres,sure of m4C1 is equal to the pressure of the -system. A plot of the vapor pressure - temperature relationship for NH4Cl is Sholm in ?i@re h. If tine tenperature and pressure of the system fall above the line, solid iSiilkC1 T i i l l not form; when either the temperaturc or the pressure or both a-e reduced sufficiently to r"c4.l bdOT
- 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 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 80 and 81: . .- . - ..... . . I ,caving the re
- 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
!<br />
overall effectiveness of these coolants is realized when the flame temperatures<br />
of the same compositions <strong>with</strong>out coolant are compared, for these are 4250°F <strong>and</strong><br />
39OOor', respectively, for the 42$ <strong>and</strong> 37dp oxygen binders. Hydroq4ammonium<br />
oxdate (HAO) is especiay effective in improving the cleanliness of the exhaust<br />
for only 22$ of this coolant produces a 2278'F flame temperature <strong>with</strong> no solid<br />
carbon in the ex!aust products.<br />
In eddition to the foregoing methods of reducing carbon in the exhaust<br />
products, it is also possible to effect a reduction by reducing the pressure at<br />
vhich the combustion reaction is carried out. An indicatior! of the extent of<br />
this Pactor can be seen in Figure 3, where the weight percent of solid carbon<br />
formed in tie Exhaust is plotted as a function of the combustion pressure for a<br />
single composition over the pressure range of 100 psia to 20,000 psia. At 20,000<br />
psia, tile carbon content of the exhaust is over 5% by weight, while at pressures<br />
below 500 psia, C$ carbon results. A reduction in flme temperature also results,<br />
xiti the vdue of 2374OP for the 20,000 psia level decreasing to 2058OP at 100 psia.<br />
67.<br />
In nddition to the formation of solid carbon, it is &so possible for mnium<br />
chloride to condense in solid crystaline particles during the reduction of flame<br />
temperature resultin& from expansion of the combustion gases through a nozzle or<br />
turbine system. 'ine presence of chlorine in the ammonium perchlorate leads to the<br />
formtion of HC1 as one of the combustion products; this in turn reacts <strong>with</strong> traces<br />
of IJH3 in the coqosition products to form iQCl when the temperature or the system<br />
falls below the value at which the vapor pres,sure of m4C1 is equal to the pressure<br />
of the -system. A plot of the vapor pressure - temperature relationship for NH4Cl is<br />
Sholm in ?i@re h. If tine tenperature <strong>and</strong> pressure of the system fall above the line,<br />
solid iSiilkC1 T i i l l not form; when either the temperaturc or the pressure or both a-e<br />
reduced sufficiently to r"c4.l bdOT
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