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Home , Carbonate, Chemical decomposition

United States Patent mi [in 3,802,993 von Fredersdorff, deceased et al. [45] Apr. 9, 1974

[54] NON-FOSSIL FUEL PROCESS FOR 86,248 1/1869 Phillips 423/579 PRODUCTION OF AND OTHER PUBLICATIONS James V. Quagliano, Chemistry Second Edition, Au- [75] Inventors: Claus George von Fredersdorff, gust, 1963, Prentice-Hall Inc., pp. 108-117. deceased, late of Oak Park, 111.; by George C. von Fredersdorff, Primary Examiner—Harvey E. Behrend administrator, Des Plaines, 111. Attorney, Agent, or Firm—Molinare, Allegretti, Newitt [73] Assignee: Institute of Gas Technology, & Witcoff Chicago, 111. [22] Filed: Dec. 27, 1971 [57] ABSTRACT [21] Appl. No.. 211,960 Hydrogen and oxygen production by fissiochemical decomposition of dioxide to produce and oxygen, followed by subsequent separa- [52] U.S. CI 176/37, 176/39, 423/219, tion of the oxygen from the carbon monoxide, and 423/579, 423/658 production of hydrogen by the action of steam on [51] Int. CI G21c 9/00 at elevated temperature followed by regeneration of [58] Field of Search 176/10, 37, 38, 39, 92 R; the product iron by carbon monoxide as sepa- 204/129; 423/648, 656, 657, 579, 594, 219, rated from the fissiochemical decomposition products 248; 252/301.1; 23/204, 221, 210-214 issuing from the nuclear reactor. The oxygen may be separated from the fissiochemical decomposition [56] References Cited products by the formation of metal oxide by reaction UNITED STATES PATENTS with reactive metals such as iron, chromium, manga- 2,558,756 7/1951 Jackson et al 423/579 nese and mercury. The process also employs steps for 2,671,013 3/1954 Watson 423/657 preventing build-up of oxygen concentrations to ex- 3,228,850 1/1966 Fellows 252/301.1 R plosive levels, steps for recovery of radioisotopes, and 3,335.062 8/1967 Feates et a! 176/92 R the generation of steam. 3,442,620 5/1969 Huebler et al .....423/658 3,535,082 10/1970 Nurnberg et al 423/657 18 Claims, 1 Drawing Figure

HYDROGEN

A? onro? PURGE —* 62 dS MAKE-OP PATENTEOAPR 9 1974 3.802.993

-N MAKE-UP HYDROGEN- COZ MAKE-UP- 2 SI

AS MAKE-UP

INVENTOR: CLAUS GEORGE VONFREDERSDORFF BY

ATT'YS 3,802,993 1 2 NON-FOSSIL FUEL PROCESS FOR PRODUCTION OF HYDROGEN AND OXYGEN SUMMARY OF THE INVENTION According to this invention, hydrogen and oxygen is produced by fissiochemical decomposition of carbon FIELD OF THE INVENTION 5 dioxide to yield carbon monoxide and oxygen. This is This invention relates to a process for generation of followed by separation of the oxygen from the carbon hydrogen and oxygen from and involving fissio- monoxide. Thereafter hydrogen is produced by the ac- chemical decomposition of . The hydro- tion of steam on iron at elevated temperature wherein gen produced may be used as a fuel to augment fossil the product iron oxide is regenerated by the carbon fuel supplies which are being rapidly depleted. The ox- 10 monoxide which was separated from the fissiochemical ygen may be used in a variety of industrial processes, decomposition products issuing from the nuclear reac- such as steel making, making, and the like. tor. The oxygen may be separated from the fissiochemi- cal decomposition products by the formation of metal BACKGROUND oxide by reaction with reactive metals such as iron, Attempts to produce hydrogen gas by the reduction 15 chromium, manganese, mercury and barium. The pro- of water in chemical nuclear reactors have been unsuc- cess also employs steps for preventing build-up of oxy- cessful primarily because the decomposition of water in gen concentrations to levels, the recovery of such reactors yields an explosive mixture of hydrogen radioisotopes, and the generation of steam. and oxygen. Further, the separation of the two gases is 20 DETAILED DESCRIPTION OF THE PREFERRED extremely difficult. Chemical scavenging of either of EMBODIMENT the two gases tends to induce an explosion of the un- separated mixture. Likewise, purely mechanical-ther- Referring now to the FIGURE, letters A, B and C modynamic separating techniques such as palladium- refer to the three major sections of the entire system: foil-diffusers also produce a similar effect. A refers to the nuclar fissiochemical decomposition of 25 C0 section, B refers to the oxygen rcovery section, The purpose of producing hydrogen by action of nu- 2 and C refers to the hydrogen production section. clear energy is to augment the rapidly depleting sources of fossil fuel supplies. In addition, sources of hydrogen In Section A, under the influence of nuclear fission are needed for applications in technology, in- energy, carbon dioxide chemically decomposes into its dustrial processes, and the like. monoxide and oxygen via the overall reaction: 30 CO i CO + % 0 .1 In contrast to prior nuclear energy generation of hy- g Ionizatio 2 drogen, conventional water- hydrogen gen- Carbon dioxide is preferably decomposed in this sec- tion by direct exposure to high-velocity fission frag- erating processes effectively separate the oxygen of the ments. The ionizing ability of these fragments strips water from the hydrogen by actual physical separtion atomic oxygen from the dioxide. The nuclear fissio- through production of the two components at different 35 chemical decomposition Section A comprises an as- locations. In steam-hydrocarbon processes or steam- sembly 1 having an exterior neutron reflector shielding metal processes the two components are separated by 2, and a centrally disposed nuclear reactor Section 3. chemical binding, which requires further processing to The nuclear reactor Section 3 is cooled by the carbon release the desired products. These processes however dioxide incoming through line 4 which moderates the utilize fossil fuels, generally in excess of the fuel value 40 temperature of the reactor to run at about 1,000° to achieved in the hydrogen production. 1,100°F. Disposed between the central nuclear reactor section core 3, and the outer neutron reflector shield- OBJECTS OF THIS INVENTION ing 2 is a COz decomposition section or sections 5, Therefore, it is an object of this invention to produce which operate at about 600°F. hydrogen from water without the use of fossil fuel as 45 In operation, the carbon dioxide to be ionizingly de- either a reactant or a source of power. composed in the nuclear fissiochemical decomposition It is another object to provide a method of producing Section A comes in through line 6 and passes into the hydrogen as a fuel from water and carbon dioxide, decomposition sections 5 and 5'. The inlet C02 is ap- which process employs nuclear energy without the proximately 400°F., but this temperature may be varied prior art dangers, inefficiences and difficulties. to provide optimum process conditions in Section C. In It is another object of this invention to provide a the COz decomposition sections 5 and 5', the ionizing novel process of producing both hydrogen and oxygen radiation and temperature operate to decompose the from carbon dioxide and water utilizing nuclear energy C02 to carbon monoxide and oxygen pursuant to reac- in a safe, easily controlled process. 55 tion 1 above. At the same time, C02 gas being recycled It is another object of this invention to provide a nu- from line 4 moderates the central nuclear reactor sec- clear energy-utilizing process which produces as prod- tion 3, which is of conventional design. Recycle COz is ucts from water and carbon dioxide, hydrogen, oxygen, exhausted out line 7, and returned to other portions of isotopes and steam. the process system as described below. Make-up C02 Still a further object of this invention will be apparent 6Q may be added to the entire process convieniehtly at that stage through line 8, or at such other plate as will assist from the description which follows. in optimizing the overall process. The following detailed description has reference to a drawing in which: In the C02 decomposition sections, the ionizing radi- The FIGURE shows one embodiment, in schematic ation may also result in the formation of carbon and flow sheet form, of a process for hydrogen and oxygen 65 carbon sub-oxide deposits via a sequence of reactions production from nuclear decomposition of carbon di- as follows: oxide and the utilization of water as a hydrogen source. CO, ionization C + 2 O — ,2

C02 ionization CO + O — ,3 3,802,993 3 4

CO + C thermal C20— ,4 The C02 decomposition stream leaves the reactor via C20 + CO thermal c302 — , 5 the lines 11 and 11' at temperature below 1,000° F. and Carbonaceous deposits are undesirable in the process preferably in the range of 500-700° F., e.g., about 600° since they hinder the continuous operation of the nu- F. Unreacted C02 in this stream is eventually recycled clear reactor carbon dioxide decomposition section. A 5 to the reactor after passing through the oxygen recov- process of the present invention eliminates or mini- ery process system B. A portion of this COz recycle mizes the elemental carbon and for- stream, which is separate from C02 recycle stream 4, mation through the use of a gasiform inhibitor such as 7, reenters the nuclcar reactor in a temperature range or nitrogen dioxide. of from 200° to 400° F, preferably 300° F, via lines 13 While there is no desire to be bound by theory, it is 10 and 14 as described in more detail below. This direct through that the mechanism for the inhibition is as fol- recycle of low oxygen content gas directly from the ox- lows: ygen recovery system B assists in preventing buildup of N2 ionization*2N 6 oxygen concentration to explosive levels in the decom- • • N + O thermal NO 7 position section of the reactor assembly. The oxygen 15 NO -)- o thfrma't NQ2 8 content of the carbon dioxide decomposition stream NOz + C thermal CO + NO 9 prior to oxygen recovery is maintained at 10 percent or ess anc N02 -f O thermal 02 + NO 10 ' > * preferably 5 to 7 percent, depending on the co 2NO+ 02^™ln/ 2 NO, — 11 concentration. Therefore, in the process of this invention nitrogen or Focusing in more detail on the oxygen recovery sys- nitrogen dioxide is used as an inhibitor, which inhibitor 20 tem B-the decomposition products exhausting from the gas is inlet into the decomposition section, for example . reactor via lines 11 and 11' enter a mercury reactor IS through line 9. The inhibitor gas may initially be de- through line 16. Liquid mercury enters the reactor at rived from nitrogen content of air. This is also conve- about 80°F> thr°ugh llne 17 wherein it is distributed nient point to add any make.up nitrogen or nitrogen into the Sas by means of a sPray head 18' or other suit" dioxide to the process through line 10. 25 able device" In the reactor 18 the h

is recycled back to the nuclear reactor section 3 via line Following the oxygen removal, a portion of the C02 47, blower 48 and recycle line 4. 25 decomposition recycle stream containing mostly car- The recovery of oxygen by the above described oxy- bon monoxide passes into the hydrogen production gen recovery system B may be done through formation section C. The reduction gas for the steam-iron portion of various types of metal oxides. The use of mercury, Qf the process containing primarily carbon monoxide, a reactive metal, has been described here in detail for passes out of the separator 24 via line 13' and 13 to CO the purposes of illustration and not by way of limita- 30 distribution valve 52 which splits the stream into a pro- tion. Other metals such as iron, chromium, manganese, Cess gas stream 53, and a recycle stream 14 as above and barium possess the capability of reacting with oxy- described. Process gas blower 54 passes the process gas gen to form thermally decomposable oxides. in line 53 to a preheater 55, where by heat exchange Mercury is a preferred material, since oxidiation of wjth gases coming off the iron oxide reducing 56, the liquid mercury releases heat which is utilized for steam 35 reducing gas is raised to a temperature on the order of generation (see steam production at lines 22 and 27 in 1,300°F. Correspondingly, the exhaust gas 58 from the Section B). The oxidation reaction must be cooled to jron oxjde reducer 56 is cooled from a temperatue of 300° F. or less, 1) to achieve nearly complete oxygen jn the range of 1,300°-1,400°F. to about 400°F. The removal from the C02 decomposition stream and 2) to preheated reducing gas in line 57 is then passed into the

minimize mercury vapor losses. The heat of reaction 40 bottom cf the iron oxide reducer 56. for mercury oxidation at atmospheric pressure, in -phe principal reactions occurring in reduction are

Btu/lb mole 02 reacted is approximately as follows: peQ + CO >Fe + C02 — 14

Fe304 + CO-—»3FeO + C02 — 15 Temp. °F2Hg( 1) +CMg)-» 2HgO(s) 4Hg(l)+02(g)-»2Hg20(s) 260 -77,800 -75,600 Reaction 14 is exothermic; however the endothermic 440 -77,000 -77,500 45 reaction 15 predominates, making the overall reduc- 620 -76,100 -75,600 tion phase endothermic. The iron oxide reducer 56 op- 672 -75,800 -75,600 2Hg(g) + 0,(g)-»2Hg0(s) 4Hg(g) + 0,(g) -»2Hg20(s) erates above 1,300° F. and preferably 1,500°-l ,700° F, 672 -126,600 -178,100 as higher temperatures favor more complete reduction 800 -125,400 -176,200 980 -123,800 -173,000 and better utilization of the carbon monoxide. The heat 1 160 -121,800 -171,000 50 requirements are supplied by preheating the reducing 1340 -1 19,500 -169,000 gas 57 with the effluent gases 58 containing mostly C02 . , , . ... . , . .. , . . , as described above, and by mass transport of an excess As much or more heat as indicated in the above table * • • , / ,'•_•• . , . , . , „ amount of iron oxides as heat carrier from the oxidizer is re transferred to mercury oxides to achieve decompo- „ , • -r,, . r vi — i- v j v v „. section 59 which is overall exothermic. The total heat sition. This is preferably accomplished by exchange 55 „ „ , •., , . , „ . r . . , . effect of reduction and oxidation in the steam-iron part with lthU e high temperature CO heat transfer stream „ .. . „ z , ,. __ of this process is exothermic. from the nuclear reactor. Oxygen gas and liquid mer- ^ • -J , , , . v c .v ' In the reduction section 56, iron oxides downcoming cury are recovered by water quench of the mercury . . ° rom the ld,zer sect,c 59 oxide decomposition products Rapid quench is pro- [ u °* f via.fill pipe'60 are reduced vided to prevent reversal of the reactions. 60 by the carbon monoxide in the reducing gas incoming The equilibrium partial pressures, in atmospheres of throu8h 57^V 1reactions described just above, oxygen and mercury vapor developed from decomposi- reactions 14 and 15. Reducing gas may be adjusted m tion of mercury oxides are approximately as given by flow to fluldlze the lron Partlcles m the reducer S6> ^ the following values: the bed may be relatlvely static allowing for gradual 65 settling by removal of the reduced iron oxides to stand- Decomposition of HgO pipe 61 from a lower portion of the reduce 56. Temperature" , „F Equilibriu„ . m Partia„ • l , Rressur„ e The reduce..d .iro n oxide. s. in the for, m of F, e an. , d FeO,, o, Hg are collected in the standpipe 61 and purged with small 3,802,993 5 amounts of N or pure C0 or mixtures thereof via line 5. Heat required for 26,900 207,000 2 2 mercury oxide 62 to strip occluded and entrained radioisotopic gases decomposition from the solids. The rate of purging is adjusted accord- 6. Mercury vapor-oxygen 13,670 105,000 gas quench ing to the system make-up requirements and to com- 7. Heat available for 64,392 497,000 pensate for the volume of circulating gases withdrawn steam generation as a sidestream for radioisotope byproducts recovery 8. Enthalpy, 100 psi 14,850 1 14,500 steam for steam- via lines 58 and 63, valve 64 and line 12. iron process Hydrogen is produced in oxidation section 59 by the 9. Enthalpy, excess steam 49,542 383,000 10. Enthalpy, raw gas 6,930 53,300 sponteneous reactions at 1,000°-1,400°F, preferably from oxidizer 1,200° F, of iron and its lower oxide with steam: 10 I 1 . Overall exothermicity 4,530 34,900 of steam-iron process Fe + H20™»FeO + H2 — 16 12. Gross heating value. 5 1.400 396,000 3 FeO + H20 "Fe304 + H2 — 17 hydrogen Process steam generated at suitable pressures in line 46 13. Heat loss allowance 17,398 132,800 B. Products is preheated in preheater 65 to 700°-900° F, typically 1. Hydrogen, SCF 161 1,240 800° F, by indirect exchange with the oxidizer effluent 15 2. Oxygen. SCF 80.5 620 3. 100 psi excess steam gasses in line 66. The preheated steam in line 67 may lb 42.7 1 329 be distributed by valve 68 directly to the oxidizer sec- C. Heat content of Hz tion 59 via line 69. A portion of the preheated steam excess steam % 77.9 77.9 is also used to lift the Fe and FeO from standpipe 61. The steam in line 69 may be adjusted to fluidized the 20 Fe-FeO bed in oxidizer section 59 if desired. As discussed above, mercury is a preferred metal for The hydrogen-rich effluent gas from the oxidizer sec- recovery of oxygen in system B. In addition to metal- tion passes through line 66, exchanges its heat in steam metal oxide recovery systems, other physical and preheater 65, and passes into scrubber 71. In the scrub- chemical recovery systems can be used. For example, ber, water input via Sine 72 and taken off via line 73 25 cryogenic separation of the C02, CO and 02 in the yields essentially pure produce hydrogen in line 74 product C02 decomposition stream 11 may be em- which contains negligible or no radioactivity. ployed, with the C02 recycled to line 4, the CO passed An analysis of the steam-iron section of this process into line 13' and the oxygen recovered as a product gas indicates that there is a 50 to 80 percent utilization of via line 75. Since the three gases have separate and dis- carbon dioxide for reduction, depending on the reac- 30 tinct phase change temperatures, mechanical compres- tion temperature in the range indicated and the inlet sion with cryogenic distillation serves as an excellent C0/C02 ratio, and a 50 to 70 percent decomposition mode of the gas separation and 02 recovery. of the steam, depending upon the reaction temperature Several chemical processes may also be employed. In in the range indicated above. one alternative of this invention, the gas from line 11 Exemplary of the advantages of the process of this 35 is fed into a reactor in contact with vapourous chlorine invention are the results given below in Table I. In this gas at low temperature. The CO in the feed gas from example, the process parameters were as follows: line 11 reacts with the chlorine to form phosgene, 1. Gas Compositions, vol % COCL2. The phosgene is easily separated from the by- product 02—C02 containing stream, and heated in a Component CO, CO NO. N O N2 o, 2 separate zone to produce CO and CL2. The CO is then a) Leaving CO, decompo- 25 50 6 3 2 14 sition section via fed into line 13' for continuation of the processing to lines 11 and 11' recover the CO values to produce H2. b) Entering iron oxide 26.6 53.2 — 3.2 2.1 14.9 reducer via line 57 In another alternative, the CO in stream 11 is reacted 69.1 10.7 3.2 2.1 14.9 c) Leaving iron oxide directly with H20 or a base such as NaOH or NH4OH reducer via line 58 45 d) Entering CO, 39.4 40.4 3.2 2.1 14.9 to form formic or its salts. The acid or salts are decomposition section then decomposed to obtain CO and water with the two via line 6 being separated easily by condensation of the water, and forwarding the CO on to system C via line 13'. 2. 40% of nuclear energy converted to chemical en- In the case of hydroxide, the sodium for- ergy in carbon dioxide decomposition products; 50 mate is obtained. At higher temperatures, the salt de- 3. 80% of incoming CO utilized in steam-iron reac- composes into hydrogen and the corresponding tions; salt, sodium oxalate. In turn the sodium oxalate is de- 4. 60% of incoming steam decomposed in steam-iron composed into , Na2COa and C02. reactions; The sodium carbonate can be reacted with water to 5. Recycle ratio of 2.3 moles C02 decomposition 55 form sodium hydroxide and C02. The C02 from the lat- gases recycled to nuclear reactor per mole reduc- ter two stages of decomposition is recycled to line 47 ing gas entering steam-iron process. and the NaOH to the contact reactor into which the Table I. Process Performance C02 decomposition gas is initially fed. In this alterna- tive embodiment, hydrogen and CO are formed, the A. Thermal. Quantities; Btu per Mole Btu per 10s 60 datum 60° F. Gas to Reducer Btu Nuclear CO later in system C being used to produce hydrogen Energy from water. This embodiment thus has the advantage of having two hydrogen source streams. 1, Energy converted in 5 1,900 400,000 COi decomposition As an alternative to the steam-iron process of system 2. Heat transferred to 71,052 548,000 C, the CO-rich gas in line 57 may be reacted directly COa stream 65 3, Preliminary cooling 9,160 70,600 with water in a conventional water-gas shift reactor. in O, removal unit There the CO reacts directly with water under catalytic 4. Final cooling in Og 1 1,080 85,400 removal unit conditions to product H2 and C02. 3,802,993 9 10

To the extent that NO builds up in C02 3. A process in claim 1 wherein said step of separat- decomposition stream 16 from input of diluting N2 via ing said 02 from said fissio-chemical decomposition line 10, the NO may be removed by chlorination as products includes the steps of: above described for the production of phosgene. The reacting the CO in said decomposition product gas product is nitrosyl chloride, NOCL, which is separated 5 stream with chlorine to form a phosgene-rich gas and then decomposed at higher temperatures to pro- stream; and duce NO and chlorine as streams separate from the heating said phosgene stream to form a CO-rich gas C02 decomposition stream. The NO separated is then stream. ejected. 4. A process as in claim 1 wherein said step of sepa- 10 The physical and thermodynamic parameters of rating said 02 from said fissio-chemical decomposition these alternative recoveries being already known, fur- products includes the added steps of: ther description is not required. The use of these sepa- reacting the CO in said decomposition product gas ration and recovery steps in the entire process of this stream with water to produce formic acid; and invention is new, and results in the improved result of heating said formic acid to produce a CO-rich gas producing hydrogen without depletion of fossil fuels or stream. 5 A the venting of C02 to the atmosphere as waste. - process as.in claim 1 wherein said step of sepa- ratin said It should be understood that modification may be 8 02 from said fissio-chemical decomposition made in the process of this invention while remaining products includes the steps of: within the scope and thereof. reacting the CO in said decomposition product gas I claim: 20 stream with a base to produce a formic acid salt; 1. A process for the production of oxygen and hydro- and gen comprising the steps of: heating said salt to produce a CO-rich gas stream. 6 A rocess as in claim 5 a. passing a first C02-rich gas stream in admixture " P wherein said base is se- lected from NaOH and NH OH with N2 or NO, to inhibit undesired decomposition , , 4 reactions into exposure to nuclear radiation in a 25 7" A Process as ln cla,m 6 wherem said base is NaOH nuclear reactor at a temperature below about and wherein said heatmg step produces hydrogen gas and s um oxalate and which mcludes the added 1,000°F. to produce an admixture of CO and 02 as °* - a gaseous fissio-chemical decomposition product steps o . heating said sodium oxalate to form sodium carbon- stream, , , . r ate and C0 ; and b. separating said 0 as a product gas stream from . .. 2 .. , . . . \ ,. . , 2, , , . reacting said sodium carbonate with water to form said tissio-chemical decomposition product streae m , , • • • _i ^^ • i_ . sodium hydroxide and C0 . to produce a CO-rich gas stream; „ . J .,.,, 2 . .. ' . . „_ . , 8. A process as in claim 1 wherein said step of sepa- c. J r r r recyclin g° a portio n of said CO-rich °ga s stream to ratinratin.. eg catrsai. dl, €1_0 - ,trr\fro mm casaim. d, tiecin-phAmip^fissio-chemica. , . l.l nApnmnrtCinridecompositio, .J rn the nuclear reactor to prevent oxygen concentra- 35 2 products includes the steps of: tion buildup therein; reacting the 0 in said decomposition product gas d. reacting steam with a source of reduced iron corn- 2 . ,. , . , stream with a metal, to produce a metal oxide and pounds to produce oxidized iron compounds and a said co_rich gas stream. and hydrogen-rich effluent gas; thermally decomposing said metal oxide to produce e. separating said hydrogen-rich gas as a product gas 40 q2 and sajd meta, stream from said oxidation; 9. A'process as in claim 8 wherein the heat required f. reacting a portion of said CO-rich gas stream with to thermaiiy decompose said metal oxide is in part pro- said oxidized iron compounds to produce a second vided by heat exchanging a heated C02 stream ob- C02-rich gas stream and reduced iron compounds; tained in moderating the temperature of said nuclear 45 reactor. g. recycling the second C02-rich gas stream pro- 10. A pr0cess as in claim 8 wherein said metal is se- duced by the oxidation of iron compounds to the iected from iron chromium, manganese, mercury and nuclear reactor to be converted to CO and 02 in barium. admixture with said first C02 stream; and n. A proCess as in claim 10 wherein said metal is h. recycling the reduced iron compound from step (f) 50 mercury. to step (d) as a source of reduced iron compounds 12. A process as in claim 1 wherein said decomposi- in said steam, tion products gaseous stream is at a temperature in the i. said process further characterized as producing range from 500° - 700°F.

6C1402 as a radioisotope by-product, 13. a process as in claim 1 wherein said radiation is 14 j. permitting said 6C 02 to build up in the C02 high velocity fission fragments. recycled to the nuclear reaction from said iron 14. A process as in claim 8 wherein, said reaction to oxide reduction reaction and, form a metal oxide is maintained in a temperature k. withdrawing a portion of said C02 recycle stream range of from about 240°F. to 700°F. and at from about and contacting said stream with a hydroxide to 1 to 100 atmospheres pressure. 14 form a stable 6C carbonate. 15. A process as in claim 11 wherein said mercury 2. A process as in claim 1 wherein said step of sepa- oxides are decomposed at a temperature above 500°F. rating said 02 from said fissio-chemical decomposition products includes the step of: 16. A process as in claim 15 wherein said decomposi- reacting the 02 in said decomposition product gas 65 tion is maintained in a range of from 700°F. to 900°F. stream with a compound selected from the group consisting of a metal, chlorine, water, or a base, to 17. A process as in claim 1 wherein said steam-iron produce an oxide and said CO-rich gas stream. reaction is maintained at a temperature in the range of 3,8( ,993 11 12 from about 1,000°F. to 1,400°F., and said reducing of water are purged with a gas selected from N2, CO., and oxidized iron compounds is maintained at a tempera^ mixtures thereof to strip occluded or entrained radio- ture above about 1,300°F. 18. A process as in claim 17 wherein the reduced iron isotopic gases from said iron compounds. compounds produced in the conversion of CO and *****

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