Europaisches Patentamt European Patent Office © Publication number: 0 461 690 A2 Dffice europeen des brevets © EUROPEAN PATENT APPLICATION © Application number: 91201214.3 © Int. CI.6: G21 B 1/00 © Date of filing: 21.05.91 © Priority: 13.06.90 US 538640 © Applicant: THE BOEING COMPANY P.O. Box 3707 M.S. 6Y-25 © Date of publication of application: Seattle WA 98124-2207(US) 18.12.91 Bulletin 91/51 @ Inventor: Momenthy, Albert Mohring © Designated Contracting States: 16215 Southeast 292nd Street DE FR GB IT NL Kent, Washington 98042(US) © Representative: Prins, Hendrik Willem et al Octrooibureau Arnold & Siedsma Sweelinckplein, 1 NL-2517 GK The Hague(NL) © Cold nuclear fusion thermal generator. © A method an apparatus are provided for generat- boron or lithium in an electrolytic cell, ing heat energy by the cold fusion of hydrogen with Rank Xerox (UK) Business Services 1 EP 0 461 690 A2 2 This invention relates to a novel method and questioning of the hypotheses associated with ef- apparatus for generating heat energy by means of forts to control high temperature fusion. cold nuclear fusion. In 1989, it was reported that deuterium ions that are galvanostatically compressed into a pal- BACKGROUND 5 ladium electrode fuse at low temperature upon application of relatively small electric currents. The It is well known that large amounts of heat fusion reaction purportedly produces helium and energy may be liberated by nuclear fission or nu- energetic neutrons by the formula clear fusion. While heat from the fission of high atomic weight fuels has been used for many years io D + D -* 3He + n + 3.2MeV. to generate electricity, no practical method of using nuclear fusion to produce energy has been discov- The production of fast neutrons requires heavy ered. shielding. To-date, most fusion research has centered on Accordingly, it is the primary object of this creating a plasma of low atomic weight constituents 15 invention to provide an alternate method of gen- such as deuterium, helium, and tritium. Fusion re- erating heat energy by cold fusion which does not actions occur when the nuclei in the plasma are produce neutron radiation and which is based on brought close enough together at a high enough the use of readily available and inexpensive fuels. energy to overcome the repulsive force between As used herein, the term cold fusion means a positively charged nuclei stripped of their electrons. 20 reaction between at least two nuclei to produce one This energy requirement is customarily expressed or more new nuclei plus energy where the reaction in terms of a temperature defined as E^k; where: constituents are not contained in a plasma. Eb is the binding energy of the reacting spe- cies; BRIEF SUMMARY k is the Boltzman Constant = 8.62x1 0-11 25 Mev/°K. In accordance with a preferred embodiment, a Using this definition, an ignition temperature of cold fusion thermal generator is provided which ° 1 08 K would be required to initiate a fusion reac- uses the electrolysis of water (H2O) in the elec- tion capable of producing an energy release in the trolyte to pack hydrogen in a specially adapted range of 3 to 18 MeV per event. Plasmas at such 30 cathode. The cathode comprises a matrix of boron temperatures cannot be contained in conventional and a molecular sieve that selectively adsorbs hy- vessels. Therefore, most of the research has been drogen and releases helium. An inert hydrogen directed towards confining plasmas in magnetic adsorbing metal such as palladium or platinum fields or pelletizing fusionable fuel so that it can be may be included in the matrix to improve electrical ignited by high energy laser or particle beams. 35 conductivity. The anode comprises an electrically Currently, "hot" fusion has not provided a net out- conductive chemically resistant metal such as put of usable energy. Monel and preferably surrounds the cathode. The In the late 1940's it was theorized that muons, electrodes are retained in a pressure vessel adja- negatively charged elementary particles which are cent a container for a heat exchange fluid. Vents about 206 times more massive than electrons, 40 are provided for gases produced by the electrolysis could be used to catalyze fusion reactions between and fusion reactions. Means are provided to replen- low atomic weight constituents such as protons and ish the electrolyte while the cell is operating. deuterons. Muon catalyzed nuclear fusion was later To operate the reactor, a current of suitable observed. density and voltage is applied across the elec- In 1982 major energy limiting drawbacks asso- 45 trades. Hydrogen is generated by electrolysis of ciated with muon catalyzed fusion were removed water and adsorbed in the cathode at high den- by the discovery that overall reaction rates were sities. The protons fuse with the boron nuclei by higher than previously predicted and yields of more the reaction than 150 fusions/muon were attainable. It had been postulated that reaction rates of 100 fusions/muon 50 p + 11B-3a(8.7MeV). would be required for the development of a reactor that has a net positive power output. This discovery The heat released by the reaction is transferred increased the interest in and promise for the prac- through the electrolyte in the pressurized vessel tical development of cold fusion. However, the near into a heat exchange fluid by conventional means. term development of commercial reactors that re- 55 The helium formed from the alpha particles and quire large numbers of muons is not likely, even if oxygen from the electrolysis are vented from the net power production is possible. Success with cell. The rate of reaction may be controlled by muon catalyzed nuclear fusion resulted in a serious controlling the rate of electrolytic hydrogen produc- 2 5 EP 0 461 690 A2 ion. mixing. A like method of producing heat by fusion Reaction vessel 12 is surrounded by larger sntails substituting Lithium for boron at the cathode vessel 13 in which a heat exchange medium 14 is and applying appropriate current density and volt- disposed. Heat from fusion reactions is transferred age to cause the following reaction 5 to medium 14 and collected for a use such as turbine power generation. Preferably, medium 14 is 3 + 5 Li -3He + a (4.0 MeV). a fluid at reactor operating temperatures that is recirculated through inlet 15 and outlet 17. Medium 14 may be a liquid metal such as sodium, for My invention will be better understood in terms io example. Larger vessel 13 is insulated with a heat of the figure and detailed description which follows. resistant layer of insulation 18, such as an ultra- lightweight aerogel of the type being developed for DETAILED DESCRIPTION the National Aeronautics and Space Administration (NASA). An aerogel would also serve as a shield The figure is a plan sectional view of a cell for 75 for any low-level radiation that may be produced by generating heat by cold fusion showing the the reaction. One major advantage of this invention hydrogen-adsorbing cathode, the anode, the reac- is that no neutron shielding is required since no or tion vessel and heat exchange vessel. insignificant numbers of neutrons are produced. Referring to the figure, a sectional view of a Electrolyte 16 in reaction vessel 12 is water- cell 1 for generating heat by cold fusion is shown. 20 based and preferably an aqueous solution of a Cell 1 is electrolytic in nature, current passing boron compound such as boric acid. Electrolyte 16 between anode 2 and cathode 3. Anode 2 com- can be replenished, as needed with water and prises ring 4 of conductive metal surrounding cath- chemicals. A further advantage of this invention is ode 3. A plurality of T-shaped fins 5 are attached that ordinary water rather than heavy water is used to ring 4 to increase its surface area. 25 in the electrolytic cell. Cathode 3 is a composite of a hydrogen ad- To operate fusion cell 1, a direct current is sorbing agent, such as an alumosilicate molecular applied across the electrodes so that hydrogen sieve, an inert and/or hydrogen adsorbing metallic ions are produced at cathode 3 and oxygen is conductor such as platinum, or a zeolyte catalyst; produced at anode 2. The voltage is preferably in and 11B isotope, preferably amorphous elemental 30 the range of from about 1 to 30 Volts, and the boron. The matrix is formed to be microporous with current density about 1 to 100 mA/cm2. The oxy- uniform lattice vacancies sized to allow retention of gen is vented from anode 2 through vent 11 and hydrogen nuclei at the active (cathodic) surface pressure relief valve 20. The hydrogen ion is held and the escape of helium or alpha particles, such in solution and adsorbed into cathode 3. The rate as the adsorption/desorption processes occurring in 35 of electrolysis is preferably controlled by adjusting packed-column gas-chromatographs or vapor-frac- current density to maximize hydrogen adsorption. tometers. The boron should be interspersed in the At this time, the exact reaction mechanism of matrix as thoroughly as possible to increase the the nuclear fusion is not understood. However, the reaction probability between itself and the ad- adsorbed hydrogen in the cathode is believed to sorbed hydrogen nuclei. Cathode 3 has a right 40 fuse with 11 B nuclei by the reaction circular cylindrical outside shape and a plurality of walls 7 and channels 8 for flow of electrolyte 16. p + 11 B -*3<* (8.7 MeV) The grid shape provides increased surface area along and within walls 7 for the cathodic adsorption where the released energy is transformed to heat of hydrogen and for nuclear reactions with boron to 45 in the reaction vessel and removed through a heat occur.