USOO8625731B2 (12) United States Patent (10) Patent No.: US 8,625,731 B2 Holden et al. (45) Date of Patent: Jan. 7, 2014 (54) COMPACT NEUTRONGENERATOR FOR (51) Int. Cl. MEDICAL AND COMMERCIAL SOTOPE G2G 4/02 (2006.01) PRODUCTION, FISSION PRODUCT G2G 4/00 (2006.01) PURIFICATION AND CONTROLLED (52) U.S. Cl. GAMMA REACTIONS FOR DIRECT USPC ............................ 376/108: 376/112:376/156 ELECTRIC POWER GENERATION (58) Field of Classification Search USPC .......................... 376/157, 108,156, 171, 172 (76) Inventors: Charles S. Holden, San Francisco, CA See application file for complete search history. (US); Robert E. Schenter, Portland, OR (US) (56) References Cited *) Notice: Subject to anyy disclaimer, the term of this U.S. PATENT DOCUMENTS patent is extended or adjusted under 35 3,748,226 A * 7/1973 Ribe et al. ..................... 376,124 U.S.C. 154(b) by 961 days. 3,778,627 A * 12/1973 Carpenter ...... ... 376, 192 4,749,540 A * 6/1988 Bogartet al. .. ... 376/133 (21) Appl. No.: 12/296,844 4,997,619 A * 3/1991 Pettus ............ ... 376,288 2004/02284.33 A1* 1 1/2004 Magill et al. ... 376/347 (22) PCT Filed: Apr. 13, 2007 2005/022O248 A1* 10, 2005 Ritter ...... ... 376/190 2008/O144762 A1* 6/2008 Holden et al. ..... ... 376/416 (86). PCT No.: PCT/US2OOTAO66668 * cited by examiner S371 (c)(1), (2), (4) Date: Oct. 10, 2008 Primary Examiner — Jack W Keith Assistant Examiner — Sean P Burke (87) PCT Pub. No.: WO2008/060663 (74) Attorney, Agent, or Firm — Craig M. Stainbrook; PCT Pub. Date: May 22, 2008 Stainbrook & Stainbrook, LLP (65) Prior Publication Data (57) ABSTRACT A neutron generator and isotope production apparatus and US 2011 FO268237 A1 Nov. 3, 2011 method ofusing the same to produce commercially and medi cally useful neutrons. The gamma,n reaction produces neu Related U.S. Application Data trons in beryllium and deuterium and the spectrum of the (60) Provisional application No. 60/792,065, filed on Apr. neutrons generated is shaped to optimize capture of the neu 14, 2006, provisional application No. 60/792,066, trons in a gamma emitting isotope. The gammas interact with filed on Apr. 14, 2006, provisional application No. target materials to produce large quantities of neutrons. 60/792,067, filed on Apr. 14, 2006, provisional application No. 60/805,541, filed on Jun. 22, 2006. 14 Claims, 3 Drawing Sheets 2 U.S. Patent Jan. 7, 2014 Sheet 1 of 3 US 8,625,731 B2 4GO i. 2CO U.S. Patent Jan. 7, 2014 Sheet 2 of 3 US 8,625,731 B2 002 × Ø U.S. Patent Jan. 7, 2014 Sheet 3 of 3 US 8,625,731 B2 US 8,625,731 B2 1. 2 COMPACT NEUTRON GENERATOR FOR Vanadium, iron and other high gamma emitting materials MEDICAL AND COMMERCIAL SOTOPE after one or Successive neutron captures or from gamman PRODUCTION, FISSION PRODUCT reactions on high-Z materials such as bismuth, lead, thorium PURIFICATION AND CONTROLLED and uranium. GAMMA REACTIONS FOR DIRECT For the purpose of this application the thermal energy ELECTRIC POWER GENERATION region is defined as /1000 electron volts to 5/10 electron volts, the epithermal energy region as 5/10 electron volts to 5000 BACKGROUND OF THE INVENTION electron Volts, the fast energy region as five thousand electron volts (five kilo electron volts, 5 keV) to one million electron 1. Technical Field 10 Volts (1 MeV) and the high energy region as above one mil The present invention relates generally to a novel method for producing neutrons in a controlled manner in a novel type lion electron volts (1 MeV) and in some cases in excess often of neutron generator, and more particularly to a novel method million electron volts (10 MeV). and apparatus for producing commercially and medically The novel neutron generator of the present invention uses useful isotopes by transmuting selected precursor isotopes 15 gamma photons to dissociate nuclei of beryllium and/or deu using gamma radiation. terium or to produce neutrons from bismuth, lead, thorium or 2. Background Art uranium. The apparatus is best Summarily described as a It is well known that neutrons produce valuable isotopes photo nuclear neutron generator and isotope producer. Using used in Scientific research, manufacturing, and medicine. the inventive apparatus, gamma photons are produced in vari Radioactive isotopes are employed in Scientific research in ous alloys or compounds of gamma emitting isotopes. Exem fields as diverse as hydrology and life Sciences. Isotopes are plary gamma emitting isotopes that function by neutron cap used in business and commerce in many manufacturing pro ture include, but are not limited to: Vanadium-50, Vanadium cess and in the production of oil and gas. The most valuable, 51, nickel-59, nickel-61, iron-57, iron-54, erbium-167, yet some of the most difficult to make isotopes, are used in the europium-151 europium-153, gadolinium-155, gadolinium diagnosis and treatment of human diseases and disorders. 25 157, bromine-79, palladium-105, palladium-107, and others It is also well known that fission in nuclear reactors pro being high-Z refractory materials such as tantalum, tungsten, duces fission products that area component of nuclear waste. rhenium and niobium functioning as a “converter in which Isotopes are currently produced by electron beams, ion energetic electrons are slowed down and emit penetrating and beams, in cyclotrons and in nuclear reactors. Some isotopes energy gamma photons. may be produced by any of the four general methods. Others 30 The inventive photo nuclear neutron generator is a very by one method alone. The science of isotope production compact "plug-in neutron generator that obviates the need involves adding or subtracting the requisite number of nucle for large reactors to produce neutrons for several applications ons (protons or neutrons) to or from the target's parentisotope and uses including: (1) production of therapeutic medical to produce the desired end product in significant quantities isotopes and other important isotopes used for the treatment with appropriate purity. 35 or diagnosis of disease or for the production of other com The transmutation reactions that change the number of mercially significant isotopes, (2) production of penetrating protons or neutrons in the isotopes include photo nuclear gamma radiation for industrial applications; (3) production of reactions wherein energetic gamma photons eject neutrons neutrons for the waste treatment of fission products from from nuclei. Also high energy neutrons are able to displace or spent light water reactor fuel to convert the fission products to eject protons from nuclei. Transmutation reactions caused by 40 shorter lived or stable isotopes; (4)) for motive power appli accelerated ions such as protons, deuterons, helium nuclei cations and (5) the gamma photons can also transmute matter and other ions collide with the nuclei of the target material to by ejecting neutrons from nuclei to accomplish transmuta change the isotope from one to another. These reactions gen tions with the same results and purpose as the aforesaid four erally do not yield the quantity of desired product material as applications and uses. efficiently as reactions involving Successive or singular neu 45 There has thus been broadly outlined the more important tron capture in the nuclear reactor. The above mentioned features of the invention in order that the detailed description reactions also are not as efficient in the treatment of fission that follows may be better understood, and in order that the products to transmuted them to shorter lived isotopes or com present contribution to the art may be better appreciated. mon stable isotopes. Additional objects, advantages and novel features of the 50 invention will be set forth in part in the description as follows, DISCLOSURE OF INVENTION and in part will become apparent to those skilled in the art upon examination of the following. The present invention relates to an inventive compact neu Furthermore, Such objects, advantages and features may be tron generator and isotope production apparatus and method learned by practice of the invention, or may be realized and of using the apparatus to produce copious amounts of com 55 attained by means of the instrumentalities and combinations mercially and medically useful neutrons. The gamma,n reac particularly pointed out in the appended claims. tion produces the neutrons in beryllium and deuterium as well Still other objects and advantages of the present invention as high-Z materials such as bismuth, lead, thorium and ura will become readily apparent to those skilled in this art from nium. The produced neutrons from gamma in reactions are the following detailed description, which shows and moderated or their spectrum is shaped so that the capture of 60 describes only the preferred embodiments of the invention, neutrons in the target isotope is maximized. simply by way of illustration of the best mode now contem The present invention advances the art by employing alloys plated of carrying out the invention. As will be realized, the fashioned from materials that emit energetic gamma radiation invention is capable of modification in various obvious to obviate the use of a reactor or a cyclotron for these appli respects without departing from the invention. Accordingly, cations when stimulated by high energy electrons. 65 the drawings and description of the preferred embodiments The novel method disclosed herein takes advantage of the are to be regarded as illustrative in nature, and not as restric energetic gamma radiation emitted from isotopes of nickel, tive. US 8,625,731 B2 3 4 BRIEF DESCRIPTION OF THE DRAWINGS tube, or foil form. This is followed by an outer ring of spec trum shaping alloy 230, and an outer ring of neutron multi This invention will be better understood and objects other plying target material 240 or gamma converting material.