546.8 I H715r C.4 National ——.—.. Academy v of Sciences I National Research Council NUCLEAR SCIENCE SERIES The Radiochemistry of Palladium —--—.———- (’-_b 4 COMMITTEE ON NUCLEAR SCIENCE L. F. CURT1~, Chairman ROBLEY D. EVANS, Vice Chairman Ntiiond Bureau of -mda Maanachusetts fnat[tute of Technology J. A. DsJUREN, Secretary Weatlqghouse Electric Corprntlon C. J. BORKOWS~ J. W. fRVD?E. JR Oak Ridge Nationnl Iahoratory Maaeachusetb Imtitute of Technology ROBERT G. COCHRAN E. D. KLEMA Texas Agricultural and Mechanical NorthweBtmn Unfvem My Co-e W, WAYNE MINNKS UnlvarBity of MIChfEWJ SAMUEL EPSTELN California fnstltute of TechMloD J. J. NICKSON Memorfnl Hoapit81, New York U. FANO Natfoml Bureau of StandwdB ROBERT L. PLATZldAN Labomtdre de Chi!de Phydque EKRBKRT GOLDSTEIN Nuolear Development Corporntlon of D. M. VAN PATTER herion Bartol Resenrch Foundation LIAISON MEMBERS PAUL C. AEBZRMXD CHARLES K. REED Abmtc EneIw Comlniaalon U. S. Air Force J. HOWARD McWLLEN WTLLfAM E. WRIGRT National SaIence Foundation OffIce of Naval Reaearah SUBCOMMITTEE ON RADIOCHEMISTRY W. WAYNE MEDifCE, Chairman EARL HYDE Urdveraiiy of Michfgm Universi@ of California (Berkeley) NATHAN BALLCNJ JUfdAN Nf.S LSEN Navaf RMBolosfcal Defenm -mtnry Hardord fdnoratoriea GREGORY R. CHOPPfN G. DAvfD O’KELLEY Florida state Unfversi& Oak Rtdge Natfonal Latmra.tary GEORGE A COWAN ELLfs P. STEINBERG ba AlanOa S431entific J.ahOrato~ Argonne Nauonal Laboratory ARTHUR W. FAKFC-L4LL PETER C. STEVENSON Universi& of W88hir@0n Urdveri3ity of CaIifOrnia (Lfvermore) JEROME HUDIS DUANE N. SUNDERMAN Bmokhaven NatfonBI Lakmratory Batt8Lle Memorfal IUBtitute CONSULTANTS HERBERT M. CLARK JORN W. Winchester Rensseher Polytschnfc Iuatilute Maeaachuseti Inntitute of TechMlosY CHEMISTRY The Radiochemistry of palladium OVE T. HfdGDAHL University ofiWichigan Ann Avbov, Michigan . P December1961 Subcommittee on Radiochemistry NationalAcademy ofSciences—National Research Council PrintedinUSA.Price$0.75.AvailablefromtbeOfficeofTechnical Services,DepartmentofCommerce,Washington25,D.C. FOREWORD The Subcommittee on Radiochemlstry i.sone of a number of’ subcommittees working under the Committee on Nuclear Science within the National Academy of Sciences - National Research council. Its members represent government, industrial, and university laboratories in the areas of nuclear chemistry and analytical chemistry, The Subcommittee has concerned itself with those areas of nuclear science which involve the chemist, such as the collec- tion and distribution of radiochemical procedures, the estab- lishment of specifications for radiochemically pure reagents, availability of cyclotron time for service irradiations, the place of radiochemistry In the undergraduate college program, etc . This series of monographs has grown out of the need for up-to-date compilations of radiochemi.cal ~,n~ormationand pro- cedures, The Subcommittee has endeavored to present a series which will be of maximum use to the working scientist and which contains the latest available information. Each mono- graph collects in one volume the pertinent information required for radiochemical work with an individual element or a group of closely related elements. An expert in the radiochemistry of the particular element has written the monograph, following a standard format developed by the Subcommittee. The Atomic Energy Commission has sponsored the printing of the series. The Subcommittee is confident these publications will be useful not only to the radiochemist but also to the research worker in other fields such as-physics, biochemistry or medicine who wishes to use radiochemical techniques to solve a specific problem. W. Wayne Meinke, chairman Subcommittee on Radiochemistry iii INTRODUCTION This volume which deals with the radlochemistry of palladlum is one of a series of monographs on radlochemlstry of the elements. There is included a review of the.nuclear and chemical features of particular interest to the radio- chemlst, a discussion of problems of dissolution of a sample and counting techniques, and finally, a collection of radlo- chemical procedures for the element as found In the litera- ture . The series of monographs will cover all elements for which radlochemical procedures are pertinent. Plans Include revision of the monograph periodically as new techniques and procedures warrant. The reader Is therefore .encouraged to call to the attention of the author any published or unpub- lished material on the radlochemlstry of-palladium which might be included In a revised version of the monograph. Iv . CONTENTS I. ,.General Reviews of the Inorganic and Analytical Chemistry of Palladium 1 II. Table of Isotopes of Palladium 2 III : Palladium Chemistry of Interest to.Radiochemists 3 A. Metallic PalJadium 4 B. Palladium Compounds 5 IV. The Analytical Chemistry of Palladium 12 A. Separation by Precipitation 12 , B. Separation by Solvent Extraction 15 c. Ion Association Systems I-6 D. Chelate Complex Systems 17 E. Separation by Ion Exchange 21 F. Separation by Paper Chromatography 24 G. Separation by Electrodepositlon 26 v. Dissolution of Samples Containing Palladium 26 .VI. Counting Techniques for Radioactive Palladium . Isotopes 29 VII . Collected Radiochemical Procedures for PalIadium 29 , References 57 v ., The Radiochemistry of Palladium OVE T. H@GDAHL* Un@?r@ty of Michigan Ann Arbov, Michigan I. GENERAL REVIEWS OF THE INORGANIC AND ANALYTICAL CHEMISTRY OF PALLADIUM 1. Mellor, J. W., “A Comprehensive Treatlae on Inorganic and Theoretical Chemistry”, Vol. XV, Longman’s Green and Co., London, 1936, pp. 592-685. 2. Remy, H., “Treatise on Inorganic Chemistry”, Vol. II, Translated by J. S. Anderson, edited by J. Kleinberg. New York, 1956, p. 340. 3. Sidgwlck, N. V., “The Chemical Elements and Their Compounds”, Vol. II, Oxford Press, London, 1950, pp. 1553-1577. 4. Friend, J. N., “A Textbook of Inorganic Chemistry”, Vol. IX, Pt. I, Charles Griffin and Co., Ltd., London, 1929, pp. 174-207. 5. Hopkins, B. Smith, “Chapters in the Chemistry of the Less Familiar Elements”, Vol. II, Chap. 21, Stipes, Champaign, Ill., 1939, pp. 1-10.. 6. Partington, J. R., “A Text-Book of Inorganic Chemistry”, MacMillan and Co., Ltd., London, 1950, p. 957. 7. Schoeller, W. R., Powell, A. R., “Analysis of Minerals and Ores of the Rarer Elements”, Jafner Publishing Co., New York, 1919, Chapter XXIV. 8. Wilson, C. L., Wilson, D. W., “Comprehensive Analytical Chemistry”, Vol. 1A, Elsevier Publishing Co., Amsterdam, 1959. k V%Siting Fellow from Central Institute For Industrial Research, Oslo, Norway . 1 9. H1.llebrand,W. F., Lundell, G. E. F., Bright, H. A., Hoffman, J. F., “Applied Inorganic Analysis”, 2nd cd., John Wiley and Sons, Inc., New York, 1953, PP. 339-385. IlcolorimetricDetermination of Traces 10. Sandell, E. B., of Metals”, InterScience Publishers, 1959, P. 711. llsol~entExtraction ‘n 11. Morrison, G. M., Freiser, H.,. Analytical Chemistry”, Wiley and Sons, New York, 1957. ..” II. TABLE OF ISOTOPES OF pAmIIJM (1,2) Method of Isotope Half Life Abun%ance Type of Decay Preparation p~% 17.5 m EC RU96(24 Mev a,2n) ~dgg 21.6 m P+,Y RU96(17 Mev a,n) Pdloo 4.1 d EC,T Rh103(50 Mev d,5n) Ag(480 Mev p) Ag(420 Mev p) Pdlol 8.5h RU%(17 Mev a,n) RU99(40 Mev a,2n) pdlo2 stable “o.96 pdlo3 1700 d EC,y Rh103”(d,2n) Rh103(p,n) pdlo2 (nJy) pdlo4 stable 10.97 pdlo5 stable 22.23 pd106 stable 27.33 pd106 ~d107m 21.3 sec IT (thn,y) pdlo8 (n,2n) ~dlo7 7X106Y 13-,no y U(n,f) ~dm stable 26.7 ~log(n,p) Pdloql 4.75m IT Pall@(thn,y) Pdllo ($25 Mev n,2n) 2 II. TABLE OP ISOTOPES OF PJIILJ!DIUM(Cont.) $ Method of Isotope Half Life Abundance Type of Decay Preparation Pdlog 13.5 h ~dllo (S20 Mev n,2n) Ag109(6.5 Mev d,2p) Pdllo (y)n) U (thn,f)’ Pdllo stable 11.81 ~dlllm Pdllo 5.5 h IT,~- (20 Mev d,p) Cd114(14 Mev n,g) Pdlll Pdllo 22 m B-,? (thn,y) Cd114(14 Mev n,u) U(thn,f) pd112 21 h P-,7 U(thn,f) pd113 1.4m p-, no y U(d,f) ~d116 (15Mev n,a) pd114 2.4 m f3-Jno y U(d,f) ~dl15 45 sec [P-1, U(d>f) no strong y III. PALLADIUM CHEMISTRY OF INTEREST TO RADIOCHEMISTS Palladium belongs to Subgroup VII, platinum metals, transition series Ru, Rh, Pd. Palladium and platlnum resemble one another more closely than any other pair In the group of platinum metals. Both elements are normally only dlvalent and tetravalent; with palla- dium the tetravalency Is much less stable than the divalency, while with platinum both are equally stable. There are some indications that monovalent palladium exists, but no such com- pound has been Isolated. Trivalent palladium compounds do 3 exist, a’ndhave been isolated, but they are unstable and are unlikely to be encountered in radlochemlcal work. Palladium Is the most abundant of the platinum metals In the earthls crust as a whole, forming about 1 part In 108, wh1Cti Is about twice as much as platinum. The element is found together with the other platinum metals, as well as In special minerals such as braggite (a mixture of platintim,palladium and nickel sulfldes), which contains about 20 per cent of palladium, potarite (PdHg) and stibiopalladlnlte (Pd3Sb). The element can also be recovered from the anode mud of copper and nickel re- fining plants. A. Metallic Palladium Palladium is a silvery-white ductile metal with a meltlng point of 1553.6° c (3). Its density Is variously given, depend- ing upon its physical condition, ranging from 11.4 at 22.5° C (4) to 11.97 at 0° C (5). It is known that absorption of hydrogen decreases the density (6). The latter reference gives the value 11.96 at 18° c: The element can be obtained in different physical states, compact and colloidal metal, palladium sponge and palladium black. The metal alloys with most metals, is a powerful catalyst (especially as the palladium black or colloidal metal), and absorbs many different gases (the most readily absorbed is hydrogen).