WO1991017546A1

WO1991017546A1 - Resonant direct nuclear reactions for energy and tritium production

Info

Publication number: WO1991017546A1
Application number: PCT/US1991/003205
Authority: WO
Inventors: Frederick J. Mayer
Original assignee: Mayer Frederick J
Priority date: 1990-05-09
Filing date: 1991-05-08
Publication date: 1991-11-14

Abstract

This invention relates to a means and apparatus for producing prime power and tritium from single-neutron, resonant, direct nuclear reactions of heavy hydrogen isotopes (8) and selected metal nuclei (10). The invention uses conventional electrical heating (21) and ion acceleration to induce nuclear reactions resulting in the generation of heat and tritium with little or no induced radioactivity or radioactive waste being produced.

Description

RESONANT DIRECT NUCLEAR REACTIONS FOR ENERGY AND TRITIUM PRODUCTION

Background of the Invention:

This invention relates to a method and apparatus for producing both primary power and tritium from the controlled release of nuclear energy in certain resonant direct nuclear (RDN) reactions. Both of the well studied processes of nuclear fission— the breaking apart of nuclei, and fusion— the combining of two light nuclei, have been, or are being, considered for nuclear energy power reactors. Fission reactors have been in operation in the United States for over thirty years but fusion reactors are still being developed as power sources. The article by A. Weinberg, Science 82, pg. 16, May 1982, gives a description of the present state of the art in the use of nuclear fission in power generation, and the article by H. P. Furth, Scientific American, 241, pg. 50, (1979) and the article by J. H. Nuckolls, Physics Today, 35, pg. 24, (1982), describe the state of research and development in the two leading concepts for using the deuterium-tritium (dt) fusion reactions for power generation.

Nuclear fission reactors operate by releasing energetic neutrons when high-Z fuel nuclei fission into two lower-Z nuclei releasing heat and other neutrons in a chain reaction. Nuclear fission reactors have had two major problems associated with their operation since their inception. The first is safety relating to a possible runaway nuclear chain reaction, i.e. an explosive release of energy and nuclear fuel. The second is the generation of nuclear waste material. The fission reactor produces a considerable amount of long-lived radioactive nuclides which must be disposed of, or stored for generations, to keep their radiations from contaminating the environment.

Fusion, on the other hand, because it makes use of energy released when two low-Z nuclei (usually deuterium and tritium, the heavy isotopes of hydrogen) fuse, results in a much smaller amount of radioactive waste, although there is some induced radioactivity caused by the energetic neutrons released in the reaction. Fusion reactors, however, to the present time, have proven too difficult technically to produce more energy than they consume, so they have yet to be used as power reactors.

The present invention has some advantages of both high-Z fission systems and the low-Z fusion systems, but does not have their disadvantages—the radioactive waste problem and the explosive problem of high-Z fission systems and the technical difficulties of the fusion systems. The present invention teaches a method and means of selecting nuclear reactions between the heavy isotopes of hydrogen, (deuterium, tritium, and combinations of the two) and certain metal nuclei, accelerating one of the interacting partners to a modest kinetic energy to create nuclear energy release in the form of low energy charged particles, X-rays, and electrons. Neither the fuel nuclei entering the reactions, nor the exiting nuclei after reacting, involve penetrating nuclear radiations (energetic neutrons and gamma rays) in the designs taught by the present invention (some designs, however, are accompanied by the low level radioactivity of tritium and some have some gamma radiation). Hence, reactors designed according to the present invention will be adaptable for use in small scale power applications such as in homes or on ships, and other transportation systems, because there will be no requirement for large and heavy shielding, or for radioactive waste disposal.

Furthermore, some reactor embodiments of the present invention may be used directly as sources of heat and tritium with very little radiation shielding. Alternatively, they can be used with energy conversion devices to power, for example, electrical generators. In conjunction with thermoelectric converters, they may be made into electrical batteries. Summary of the Invention:

The principle objective of the present invention is to provide a means and apparatus to produce a source of prime power in the form of heat from the nuclear reactions of the heavy isotopes of hydrogen, deuterium (d) and tritium (t) (or mixtures of these two) and selected metal nuclei. A further objective of the present invention is to provide a means and method of generating tritium for its various uses. The method makes use of low energy deuterons or tritons (herein called projectile nuclei) energized by either conventional heating techniques or conventional ion accelerators. The projectiles are allowed to bombard specially selected nuclei (herein called target nuclei) dispersed in various matrices, often imbedded in metals; the nuclear reactions, in turn, produce heat, tritium, or a combination of both. The heat is transferred from the reactor by various conventional heat extraction techniques to be used either directly in the form of heat, or, with the use of heat exchangers, to be delivered to energy conversion devices for further processing. The tritium gas produced is also collected by conventional isotope separation techniques for later use in other reactors of the type taught by this invention or in other end uses.

The nuclear reactions that are employed in the present invention are of the sub-Coulomb barrier type and make use of resonant, single-neutron, direct nuclear reactions of the heavy hydrogen isotopes on selected metal nuclei. Some reactions of this type are displayed in Tables I and II. The reactions in the Tables are not meant to be exhaustive, only exemplary. The present invention, however, teaches the method of selection for the reactions of choice.

The deuterium and tritium projectile nuclei are added to the reaction vessels either as a gas in some embodiments or in chemical compounds which are liberated with the addition of heat in other embodiments. The metal target nuclei are deployed either as a solid metal, a molten metal, a metal vapor, or in mixtures with other metals of similar form. The choice of the deployment of the nuclei depends upon the particular embodiment chosen and the characteristics desired. Finally, although conventional heating and ion acceleration techniques used in conjunction with solid metal target configurations will be the preferred embodiments of this invention, designs incorporating other specially selected solid, liquid or gas targets of deuterium, tritium and selected metal target nuclei in resonant, direct nuclear reactions represent alternative embodiments of this invention.

Brief Description of the Drawings:

FIGURE 1 shows a schematic representation of one embodiment of the present invention that allows gaseous heavy hydrogen isotopes to flow through a electrically-heated, cylindrical, metal reaction vessel. Nuclear reactions in the metal tube walls produce further heating, additional tritium, or both, in the reactor vessel.

FIGURE 2 shows a schematic representation of an embodiment of the present invention wherein gaseous heavy hydrogen isotopes are percolated through heated target metal chips or molten target metal in a reaction vessel wherein nuclear reactions produce additional heat, tritium, or both.

FIGURE 3 shows a schematic representation of an embodiment of the present invention wherein the nuclear reactions are produced near the interface between two materials energized by an electrical heating current. One of the materials contains the heavy hydrogen isotopes, and the other material contains the selected metal nuclei.

FIGURE 4 shows a schematic representation of another embodiment of the present invention wherein a reactor is energized by electrical heating rods imbedded between two reactive material slabs, one of which contains the heavy hydrogen isotopes and the other contains the selected target metal nuclei. Additional heat, tritium, or a combination of both are produced by the nuclear reactions.

FIGURE 5 shows a schematic representation of another embodiment of the present invention wherein beams of heavy hydrogen isotopes are located around a flowing gas of selected target metal nuclei. Additional heat, tritium, or a combination of both are produced by the nuclear reactions.

FIGURE 6 shows a shematic representation of another embodiment of the present invention wherein heavy hydrogen isotopes from a conventional ion source flow through an accelerating grid and bombard a reaction plate made of selected metal nuclei. The nuclear reactions in the reaction plate produce heat, tritium, or a combination of both.

FIGURES 7-A,B shows a schematic representation of the side 7-A and end 7-B views of another embodiment of the present invention wherein heavy hydrogen isotopes, extracted from a conventional ion source, flow through an accelerating grid and then penetrate capillary tubes constructed of a selected target metal nuclei— the tubes effectively confine the heat to the interior of the structure, and the heat is conducted to a coolant flowing through a second set of perpendicularly disposed, embedded capillary tubes. Additional heat, tritium, or a combination of both are produced by the nuclear reactions.

FIGURE 8 shows a schematic representation of another embodiment of the present invention wherein a plasma arc of hydrogen-isotope gases are contained within a specially-selected metal reactor vessel. The arc-energized hydrogen-isotope gases penetrate the reactor walls producing nuclear reactions which then produce heat, tritium or a combination of both.

FIGURE 9 shows a schematic representation of another embodiment of the present invention wherein heavy hydrogen nuclei are electrically-driven through an electron-donor metal and into selected metal target nuclei to generate heat, tritium, or a combination of both.

Figure 10 shows a schematic representation of another embodiment of the present invention wherein small, coated metal spheres containing heavy-hydrogen isotopes are allowed to generate heat, tritium, or a combination of both.

Description of Preferred Embodiments:

All of the embodiments of this invention make use of low energy heavy hydrogen isotopes as projectile nuclei. Since low energies are utilized, the projectile nuclei may be simply energized by the addition of heat to a material containing them. Alternatively, the projectile nuclei may be accelerated by conventional electrostatic ion acceleration methods up to a kinetic energy of less than a few keV. The target metal nuclei may be in elemental form as a solid, liquid or vapor, or they may be one component of a mixture of metals or contained in chemical compounds.

The specific design will depend upon the nature of the heat and tritium source desired, upon engineering considerations, and upon material properties such as specific heats, thermal conductivity, structural strength, chemical reactivity, etc.

Thermal Acceleration — The projectile nuclei may be accelerated by the addition of heat supplied by electrical resistive heating, by plasma heating, by chemical reaction heating, or even by unconventional sources such as microwave or laser heating. Although the thermal acceleration embodiments of the present invention that are herein presented make use of electrical heating techniques, it will be obvious that other less conventional techniques will be easily adapted as other embodiments of the present invention. Raising the temperature of the material containing the target nuclei facilitates the diffusion of the projectile ions in the target nuclei matrix, thereby raising the nuclear reaction rates within the reacting materials.

Electrostatic Acceleration — The projectile nuclei may be accelerated by a variety of different well-known electrostatic field accelerators. These accelerator techniques (and limitations) are clearly presented in Chapter 5 of the recent text Cauldrons in the Cosmos by C. E. Rolfs and W. S. Rodney, and are herein considered to be conventional. In the present applications, the projectile energies of only up to a few keV are required and are easily obtained by the conventional techniques.

The choice of the ion acceleration method will depend upon engineering considerations, the projectile current level requirements, ion source lifetime considerations, and cost considerations. Projectile beam power requirements will range up to a few kilowatts, and beam currents up a few hundred milliamperes.

Nuclear Reactions and Barrier Penetration — The present invention makes use of single-neutron, resonant direct nuclear (RDN) reactions (see, for example, Direct Nuclear Reactions, by N. K. Glendenning) at energies below the Coulomb barrier. Sub-Coulomb barrier reactions are those reactions in which the kinetic energy in the collision of a projectile nucleus and a target nucleus is substantially less than the Coulomb barrier energy, E_b = Z Z_te²/R_n, where the Z's are the projectile and target charges, e is the electron charge, and Rn is the nuclear radius (standard nuclear reaction notation is used throughout this application). The barrier energies are quite high, millions of electron volts, but quantum mechanical tunneling, and electron screening effects allow projectile nuclei with substantially less energy to penetrate this high-energy barrier and to produce the nuclear reactions. In general, kinetic energies of no more than a few keV will be sufficient to initiate the nuclear reactions because of an electron screening effect.

In the single-neutron RDN reactions, the projectile nucleus either donates a neutron to a target nucleus or acquires a neutron from the target nucleus. In the specific case considered here, a deuteron may "pick-up" a neutron from the target nucleus to creating a triton, or a triton may be "stripped" of a neutron to destroy a triton. These "stripping" and "pick-up " reactions have been studied extensively at high impact energies since the early days of nuclear physics research (see for example, Introductory Nuclear Physics by David Halliday) . The target nuclei in these reactions are chosen so as to have the nuclear energy change in the reaction (the Q of the reaction) to be both positive (an exothermic reaction) and, usually, small (in nuclear terms). The RDN reactions chosen in the present invention have higher probability of occurance than do non- resonant reactions because of their substantially increased cross- sections at very low incident projectile energies. Although it will be usual, and useful for radiation reduction, to select an RDN reaction that has a small energy release (Q), there are some designs in which a large energy release is useful for inducing secondary nuclear reactions. An example of such a higher Q RDN reaction is listed as reaction 15 of Table II.

A deuteron or triton may "capture" an electron, either atomic, plasma, or conduction (in the case of a metal lattice), to charge- neutralize the projectile by forming a short-lived, so-called, "virtual" state; these nuclei may be thought of as virtual dineutrons or virtual trineutrons. This virtual state formation has been described recently by C. J. Benesh, J. R. Spence, and J. P. Vary in the Bulletin of the American Physical Society, Vol. 35, pg. 1673 (1990), for the case of the electron deuteron virtual state. With the virtual state formation, the projectile nucleus may now penetrate the Coulomb barrier to a distance very close to the surface of the target nuclei. This effective charge-neutralization acts, in its penetration of the Coulomb barrier, in a manner similar to the much more familiar situation of the deuteron or triton having a very much higher kinetic energy that penetrates the Coulomb barrier.

With charge-neutralization allowing the close approach of the projectile nucleus to the target nucleus, quantum mechanical tunneling allows the neutron transfer to take place thereby releasing the Q of the nuclear reaction.

A list of the RDN reactions which create a triton (tritium producers) in a collision between deuterons and some stable nuclei is displayed in TABLE I. A list of RDN reactions which destroy tritons (tritium consumers) in collisions of tritons with some stable nuclei is displayed in TABLE II. Included in the TABLES are the radiations of the product heavy particles, and the Q of the reaction in MeV. The energy change in these reactions is the energy equivalent of the mass defect between a deuteron and a triton, here denoted as Δ_dt , and is equal to either -1.8141 or +1.8141 MeV depending upon whether a neutron is created or destroyed in the RDN. The last column in TABLES I and II displays the ratio of the reaction Q to the exchange energy; values of the ratio that are closer to zero are the important low Q resonance reactions. The reactions that are closer to being "on resonance" are expected to have a higher reaction probability. The product radiations displayed in the second column of TABLE II show that only relatively low energy γ rays, X-rays and short range beta particles (electrons) result from these RDN reactions. All of the product radiations are strongly absorbed in the reacting material itself and in the reaction vessel, making heavy radiation shielding unnecessary. High-Q resonant reactions, an example of which is reaction 15 of Table II, are also possible but will be accompanied by higher energy secondary reactions.

The RDN reactions are (usually) chosen, not only because of their enhanced reaction cross-section, but also to keep a small value of the kinetic energy of the exiting particles. The low-Q of these reactions further reduces the induced radioactivity during the slowing down of the deuteron or triton because this low kinetic energy is insufficient to produce excitation of most nuclear levels in the nuclei they encounter.

Notice that the tritium producers in TABLE I also generate some heating while generating the tritium, whereas the tritium consumers of TABLE II only produce the nuclear heating.

The RDN reactions, therefore, provide a greatly increased probability of nuclear reaction to occur at the low energies, far below the Coulomb barrier. More details of the physics of resonant nuclear reactions may also be found in Cauldrons in the Cosmos by C. E. Rolfs and W. S. Rodney, and more detail about the direct nuclear reactions can be found in Direct Nuclear Reactions by Glendenning. Reactor Embodiments and Design Characteristics — All of the following embodiments of the present invention will use either deuterium, tritium, or a combination of the two as well as target nuclides chosen from TABLES I and II or others taught by the present invention. The projectile and target nuclear materials may be deployed in various configurations, but the preferred embodiments are displayed in the attached FIGURES.

FIGURE 1 is a schematic representation of one embodiment of the present invention. A cylindrical metal reaction vessel 10 is heated by an electrical current injected through electrodes 21 and flowing through the reaction vessel walls. The reactant gases 8, deuterium, tritium, or a mixture of both is allowed to flow into the reaction vessel through inlet and outlet ports 6. The heated metal dissolves some of the reactant gases and produces the nuclear reactions in the metal walls futher heating the vessel walls. The reaction vessel walls may require a diffusion barrier or coating to be provided as a layer of ceramic 57 for example quartz, alumina, or manganese oxide to prevent the hydrogen isotopes from escaping from the reaction vessel's exterior surface. This diffusion barrier may be required in other embodiments described below, but are not shown in the figures to simplfiy the description. The additional nuclear reaction generated heat is then extracted by conventional, conductive cooling by a coolant flowing through cooling tubes 3. When sufficient heating is being generated, the electrical heating of the metal cylinder can then be removed. The exit gas may be enriched in tritium if a sufficient amount of the tritium producer (TABLE I) reactions have been activated.

FIGURE 2 is a schematic representation of another embodiment of the present invention. A cylindrical reaction vessel 31 is fitted with electrical heating coils 52, and contains the metal target nuclei material 17 which may be either in the form flakes or chips depending upon whether the temperature is kept below the melting temperature of the metal pieces, or may be molten metal if the heating is sufficient to keep the temperature above the metal melting point. The heavy hydrogen isotopes are allowed to come in contact with the target metal reactants by percolating the gases (introduced through an inlet at the bottom) through the target metals. Nuclear heat that is produced in the reactions is extracted by conventional, conductive cooling tubes 12 surrounding the vessel.

As in the previous embodiment, when sufficient heating is being generated, the electrical heating supplied by the coils can then be removed. The exit gas 22 is allowed to flow out of the reaction vessel through an outlet at the top. The exit gas may be enriched in tritium if a sufficient amount of the tritium producer (TABLE I) reactions have been activated.

FIGURE 3 is a schematic representation of another embodiment of the present invention which is comprised of a metal target bearing solid cylinder 16, solid compound containing deuterium, tritium, or mixture of both 4, an electrical heating rod 24, and a cooling tube 7. In this embodiment, the electrical resistive heating of the heavy hydrogen bearing material 4 allows the projectile nuclei to diffuse into the metal target nuclei imbedded in the cylindrical metal 16 and to undergo the nuclear reactions which produce heat and possibly tritium. The heat is extracted by the conventional, conductive cooling tube around the metal cylinder. As in the previous embodiments, when sufficient nuclear heating is being generated, the electrical heating supplied by the rod 24 may then be removed. Tritium that is generated will remain imbedded in the metal matrix and can be removed with later material processing.

Another embodiment of the present invention that is similar to that of FIGURE 3 is comprised of the same components as that embodiment except that the projectile ion material is uniformly dispersed as a mixture in the metal target material. Again, the electrical heating provides energy to the projectile ions which then diffuse through the metal target nuclides to generate the nuclear reactions.

FIGURE 4* is a schematic representation of another embodiment of the present invention which also makes use of contiguously mounted solid reactant materials. The heavy hydrogen isotopes are components of the solid material 64 which is in direct contact with the metal nuclei bearing material 44. Electrical heating is supplied through resistive rods 18 imbedded in the reactant materials. The electrical heating provides energy to the projectile ions which then diffuse into the metal target nuclei material near the interface. The nuclear reaction heating keeps the hottest zones localized to thin layers near the interaction interface. The heat, from the initiated reactions, is conducted outward in both directions, and removed by the heat exchange fluid 33 flowing on both sides of the slab reactor. The heat exchange fluid carries the heat away, either for direct use, or to energy conversion devices for further processing. As in the previous embodiments, when sufficient heat is being generated, the electrical heating supplied by rod 18 may then be removed. Tritium that is generated will remain imbedded in the metal matrix and can be removed with later conventional materials processing.

FIGURE 5 is a schematic representation of another embodiment of the present invention wherein the target nuclides are a part of a flowing gas or metal vapor (at pressures above 10 millitorr and below 100 atmospheres) into which are directed the projectile ion beams. In this embodiment, the target nuclide gas which may be only part of, or all of, the gas atoms, enters at 20 from a heat exchanger (and tritium recovery facility) and flows into the interaction region where upon the projectile ions created in ion source 9, are brought to the interaction region through drift tubes 2, and collide with the target gas atoms. The nuclear reactions then release energy into the gas which, with increased temperature, exits at 50, flowing out of the interaction region. The excess energy is then recovered in a conventional heat exchanger, and tritium may be recovered and the gas is then recycled back into the interaction region. As the target atoms are consumed, they are replenished by adding target gas atoms from supply source 5, up-stream of the interaction region.

FIGURE 6 is a schematic representation of another embodiment of the present invention, wherein the projectile ion source and the target material are located in close proximity to form a reactor vessel in a form which closely resembles a high-power diode vacuum tube. In an evacuated space (pressure less than 1 millitorr), a conventional ion source generates projectile ions in a beam 1 (with beam currents up to a few hundred milliamperes and beam powers up to a few kilowatts) which is allowed to bombard reaction plate 14 through a beam defining aperature 15 and through an accelerating cathode grid 23. The plate 14 is constructed of, at least some amount of a reactive metal nuclide of the type selected from the nuclides in TABLE I or II, or others taught by the present invention. Reaction plate 14 is constructed with small diameter capillary tubing or channels through which a heat transfer fluid (usually water) flows to carry away the excess heat from the nuclear reactions produced in the thin layer at the surface of the plate. The fluid is sent to a heat exchanger and the energy extracted either for direct heating purposes or for use in a conventional energy conversion device such as a turbine electrical generator or thermoelectric converter. In this embodiment of the present invention, the ion beam supplies the thermal energy and reactant metal plate penetration to produce the nuclear reactions.

FIGURE 7-A is a schematic representation of another embodiment of the present invention that uses a closely packed system of thin hollow tubes 40 oriented at a small angle to the incoming ion beam 11 generated from a conventional ion source 19 (with beam currents up to a few hundred milliamperes and beam powers up to a few kilowatts) and accelerated by cathode grid 26. The purpose of the "honeycomb" reaction plate is to confine the incoming ions to the interiors of the tubes, so the nuclear reactions that take place will deposit their energy inside the structure instead of at a surface where some of the energy would be lost perpendicular to the surface. The capillary tubes may be constructed from a composite material, one component of which, is a target metal nuclide chosen from TABLE I or II or others as taught by the present invention. Alternatively, the target nuclide may be one component of a thin layer of material deposited on the inside of the capillary tubes. A second set of capillary tubes is provided, preferrably perpendicular to the ion beam tubes, to carry the heat exchange fluid through the structure in order to remove the heat that is subsequently sent to a heat exchanger or other energy conversion devices. FIGURE 7-B shows a rear view of the "honeycomb" reaction structure. Figure 8 is a schematic representaion of another embodiment of the present invention that makes use of a plasma arc to energize the heavy hydrogen nuclei. In this embodiment, heavy hydrogen gases, in some cases mixed with buffer gases (like argon or helium) are admitted through tubes 36. A high current arc is struck between the electrodes 38. The gaseous plasma, 54, so-formed, energizes the hydrogen nuclei. Some energized nuclei then drift to the specially- selected RDN metal wall, 42, of the reactor vessel, diffuse into the metal wall and undergo nuclear reactions releasing heat, tritium, or both. The metal vessel walls are constructed with insulating ceramic rings, 33, that prevent the short-circuiting of the plasma-arc. The metals are selected from those nuclides in Tables I or II. The heat produced is extracted in a conventional manner by circulating cooling water through tubing, 46, surrounding the reactor vessel.

Another embodiment of the present invention makes use of a reactor vessel similar to that of Figure 8 except that this embodiment incorporates the selected RDN metal nuclides of Tables I and II, in a gaseous form mixed directly with the hydrogen- isotope gases directly in the plasma arc of Figure 8, and again extracting the heat by conventional cooling methods.

Yet another embodiment of the present invention makes use of a reactor vessel similar to that of Figure 8 except that the high current arc to energize the heavy hydrogen plasma, a microwave energy source is connected to the cylindrical reactor to energize the hydrogen-isotopes.

In FIGURE 9, a direct-current electrical supply, 30, is connected to a cathode, 45, and an anode, 49, between which are located a RDN metal target, 41 (selected from Tables I and II), an electron-donor metal, 39, and a heavy- hydrogen conductor, 51 [see S. Chandra in Superionic Solids and Solid Electrolytes, (pg. 185), edited by A. Laskar and S. Chandra, Academic Press, Inc. 1989] Protons, deuterons, or tritons from the heavy-hydrogen conductor, 51, are accelerated by the impressed electrical potential. There are numerous examples of these hydrogen conductors, including H₃PMo₁₂O₄₀.29H₂O, H₃PW₁₂O₄₀.29H₂O, α-Zr(HP0₄)₂.2H₂0, H⁺(H₂0)n-β/β"Al₂0₃, Al(OH)₃.3H₂0, Zr0₂.nH₂0, and others (see Chandra reference). Depending upon the application, these hydrogen conductor materials will have the hydrogen(H) nuclei replaced by deuteriums (D) or tritium(T). The transported hydrogen nuclei proceed through the electron-donor metal, 39, which has been specifically chosen to have conduction electrons with energies that match the "virtual" state electron energy, and therefore transform the charged nuclei into charge-neutralized "virtual" particles. Examples of electron-donor metals may include Cu, Ag, Be, Fe, Mn, Zn Mg, and Al, and others. The "virtual" particles continue into the RDN metal, 45, where they undergo nuclear reactions liberating nuclear heat, tritium or a combination of both. A reservoir, 28, of the hydrogen-isotope gas may be located contiguous to the anode to provide an additional source of gas. Alternatively, if sufficient heavy-hydrogen is contained within the hydrogen conductor, 51, the additional gas from 28 may not be required, simplifying the design. Although not shown, the heat and tritium produced may be extracted from 45 by conventional methods.

Figure 10 shows another embodiment of the present invention wherein a small sphere of heavy-hydrogen bearing material 58, is surrounded by metal layer 59 chosen from TABLES I or II which is further surrounded by a diffusion barrier layer of ceramic 60. The overall sphere dimension is to be from a few tens of microns up to many centimeters. Many such spheres grouped together may be heated by conventional flames or electrical methods to initiate the release of nuclear energy which then maintains the heat and tritium production in the grouping of spheres. Simple dispersal and immersion in a cooling liquid then may quench the reactions.

It should be clear that the invention as described herein, can be practiced with apparatus other than that depicted. In its most basic form, a reactor should include means for energizing a first nucleus, means for retaining a second nucleus, means for contacting the energized first and second nucleus so as to produce the desired reaction and means for extracting heat generated by the reaction. As noted above, the energization may comprise energization of either one or both of the nuclei and energization of the nucleus or nuclei may be accomplished either while they are separated or after admixture of the two nuclei.

It should also be noted that while in the foregoing, it has generally been specified that the low Z material be energized and directed to the high Z material, which is termed the target material, such a procedure need not be the case. For example, the high Z material may be energized and directed to impact the low Z material. In one such embodiment, the low Z material may be contained in a solid matrix in the form of a tritide or deuteride and subsequently impacted with a high-Z ion, particle beam or the like. Also, the reactions set forth in TABLES I and II are not meant to be limitations upon the practice of the present invention but are merely illustrations of some reaction pairs which may be advantageously employed in the practice of the present invention. By reference to the teaching hereinabove, one skilled in the art could readily select other pairs of nuclei which may be employed with equal advantage. While the foregoing reactions are of the type which exchange one neutron, clearly multiple neutron exchange reactions are contemplated within the scope of the present invention.

In view of the foregoing, it should be apparent to one skilled in the art that many modifications and variations of the present invention may be practiced in view of the teaching herein. The foregoing discussion is merely meant to represent particular embodiments of the present invention and is not meant to be a limitation upon the practice thereof. It is the following claims, including equivalents, which define the scope of the invention. TABLE I

Q(MeV) Q/IΔdtl

0.1045 0.058

0.0259 0.014

0.1259 0.07

0.2959 0.163

0.0459 0.025

0.0759 0.042

0.1573 0.087

0.0859 0.047

0.0059 0.0032

TABLE II

Product

Tritium Producers Radiations Q(MeV) Q/IΔdtl

1.) Pt¹⁹²(t,d)Pt¹⁹³ ET, Ir L X-rays 0.0241 0.0175

2.) Hf¹⁷⁶(t,d)Hf¹⁷⁷ stable 0.1141 0.063

3.) Tm¹⁶⁹(t,d)Tm¹⁷⁰ β-(0.97MeV), e, Yb X-rays 0.1641 0.09

4.) Er¹⁶⁶(t,d)Er¹⁶⁷ stable 0.1841 0.10

5.) Hθ¹⁶⁵(t,d)Hθ¹⁶⁶ β-(1.84MeV),e^', Er X-rays 0.0741 0.060

6.) Tb¹⁵⁹(t,d)Tb¹⁶⁰ β-(1.74MeV),e-, Dy X-rays 0.1341 0.074

7.) Gd¹⁵⁶(t,d)Gd¹⁵⁷ stable 0.0941 0.05

8.) Eu¹⁵³(t,d)Eu¹⁵⁴ β-(1.85MeV),e-, Gd X-rays 0.1341 0.07

9.) Eu¹⁵¹(t,d)Eul52 β^"(1.48MeV),e,Gd X-rays 0.0341 0.02

10.) Te¹²⁶(t,d)Te¹²⁷ β^"(1.48 eV),_e;i X-rays 0.0641 0.035

11.) Sb¹²³(t,d)Sb¹²⁴ β^_(2.31MeV), γ rays 0.1701 0.094

12.) Pd¹⁰⁶(t,d)Pd^107* Pd X-rays,e^' 0.166 0.091

13.) Sr⁸⁸(t,d)Sr⁸⁹ β-(l .46MeV), γ rays 0.1441 0.08

14.) Ti⁵⁰(t,d)Ti⁵¹ β-(2.14MeV), γrays 0.1231 0.068

15.) Mg²⁶(t,d)Mg²⁷ β^'(l .75MeV), γ rays 0.1831 0.10

16.) Ti ⁷(t,d)Ti⁴⁸ stable 5.3694 2.96

Claims

What is claimed is:

1. A nuclear reactor comprising: means for energizing a first nucleus to an energy of no greater than 3 keV; means for containing a second nucleus therein; means for contacting said energized first nucleus with said second nucleus, whereby a neutron transfer reaction occurs between said nuclei under conditions wherein the energy of the energized nucleus is substantially below the Coulomb barrier energy for said reaction and said reaction generates products having a kinetic energy substantially in excess of the energy of the energized nucleus, which kinetic energy is dissipated to the reactor as thermal energy; and means for withdrawing thermal energy from the reactor.

2. A reactor as in claim 1, wherein said means for energizing the first nucleus comprises electrical heating means associated with the reactor.

3. A reactor as in claim 1, wherein said means for energizing the first nucleus comprises means for electrostatically accelerating said first nucleus.

4. A reactor as in claim 1, further including a matrix material operative to retain at least one of said first and second nuclei.

5. A reactor as in claim 1, wherein said means for energizing said first nucleus is further operative to energize said second nucleus.

6. A reactor as in claim 1, wherein said second nucleus comprises at least a portion of the walls of a vessel configured to retain and receive said first nucleus therein.

7. A reactor as in claim 1, wherein said first nucleus is in a gaseous form and said vessel is configured as a matrix of hollow tubes disposed to permit flow of said first nucleus therethrough.

8. A nuclear reactor comprising: means for providing a first group of nuclei; means for energizing said group of nuclei; a body of material including a second group of nuclei capable of undergoing a resonant direct nuclear reaction with said energized first group of nuclei; means for contacting said energized first group of nuclei with said body of material whereby a neutron transfer reaction occurs between said first and second groups of nuclei under conditions wherein the energy of the energized nuclei is substantially below the Coulomb barrier energy for said reaction and said reaction generates products having a kinetic energy substantially in excess of the energy of the energized group of nuclei, which kinetic energy is dissipated to the reactor as thermal energy; and, means for withdrawing thermal energy from the reactor.

9. A reactor as in claim 8, wherein: said means for providing said first group of nuclei comprises means for providing a gas containing said first group of nuclei; said means for energizing said first group of nuclei comprises means for establishing a plasma including said first group of nuclei, and said body of material including said second group of nuclei is a solid body disposed so as to at least partially enclose said plasma, whereby energized members of said first group of nuclei diffuse into said body of material.

10. A reactor as in claim 8, wherein said body of material including said second group of nuclei is a gaseous body.

11. A reactor as in claim 8, wherein said means for providing a first group of nuclei comprises a heavy hydrogen conductor material having a heavy hydogen isotope contained therein and said means for energizing said first group of nuclei comprises a pair of electrodes disposed with said heavy hydrogen conductor material therebetween.

12. A reactor as in claim 8, wherein at least one of said electrodes is at least partially comprised of said body of material including said second group of nuclei.

13. A reactor as in claim 12, further including an electron donor metal disposed between said heavy hydrogen conductor material and said body of material.