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58-608: The Ames process was used on August 3, 1942, by a group of chemists led by Frank Spedding and Harley Wilhelm at the Ames Laboratory as part of the Manhattan Project . It is a type of thermite -based purification, which was patented in 1895 by German chemist Hans Goldschmidt . Development of the Ames process came at a time of increased research into mass uranium-metal production. The desire for increased production

116-643: A "bomb") and heating it. They were able to reproduce Goggin's results in August 1942, and by September, the Ames Project had produced a 4.980-kilogram (10.98 lb) ingot. Starting in July 1943, Mallinckrodt, Union Carbide , and DuPont began producing uranium by the Ames process, and Ames phased out its own production by early 1945. As a result, the Ames Laboratory never moved to Chicago, but Spedding

174-402: A Bachelor of Science (B.S.) degree in chemical engineering in 1925 and a Master of Science (M.S.) in analytical chemistry the following year. As an undergraduate, Spedding took issue with the prevailing explanation by Friedrich August Kekulé of how the six carbon atoms in benzene hold together and proposed an alternate explanation. His professor, Moses Gomberg , recognised this as being

232-880: A few percent of divinylbenzene . Crosslinking decreases ion-exchange capacity of the resin and prolongs the time needed to accomplish the ion-exchange processes but improves the robustness of the resin. Particle size also influences the resin parameters; smaller particles have larger outer surface, but cause larger head loss in the column processes. Besides being made as bead-shaped materials, ion-exchange resins are also produced as membranes. These ion-exchange membranes , which are made of highly cross-linked ion-exchange resins that allow passage of ions, but not of water, are used for electrodialysis . Four main types of ion-exchange resins differ in their functional groups : Specialised ion-exchange resins are also known such as chelating resins ( iminodiacetic acid , thiourea -based resins, and many others). Anion resins and cation resins are

290-412: A high pH because they undergo deprotonation. They do, however, offer excellent mechanical and chemical stability. This, combined with a high rate of ion exchange, make weakly base anion resins well suited for the organic salts. For anion resins, regeneration typically involves treatment of the resin with a strongly basic solution, e.g. aqueous sodium hydroxide. During regeneration, the regenerant chemical

348-635: A large surface area on and inside them where the trapping of ions occurs along with the accompanying release of other ions, and thus the process is called ion exchange. There are multiple types of ion-exchange resin, that differ in composition if the target is an anion or a cation. Most commercial resins are made of polystyrene sulfonate , followed up by polyacrylate . Ion-exchange resins are widely used in different separation , purification, and decontamination processes. The most common examples are water softening and water purification . In many cases, ion-exchange resins were introduced in such processes as

406-607: A lecture in Leningrad . When Spedding returned to the United States in 1935, the country was still in the grip of the Great Depression, and the job market had not improved. He was George Fisher Baker assistant professor at Cornell University from 1935 to 1937. It was another temporary position, but it did allow him to work with Hans Bethe . At one point he drove out to Ohio State University hoping to find

464-409: A more flexible alternative to the use of natural or artificial zeolites . Also, ion-exchange resins are highly effective in the biodiesel filtration process. Most typical ion-exchange resins are based on crosslinked polystyrene . The actual ion-exchanging sites are introduced after polymerisation. Additionally, in the case of polystyrene, crosslinking is introduced by copolymerisation of styrene and

522-414: A much lower concentration of magnesium and calcium ions in solution than was started with. The resin can be recharged by washing it with a solution containing a high concentration of sodium ions (e.g. it has large amounts of common salt (NaCl) dissolved in it). The calcium and magnesium ions migrate from the resin, being replaced by sodium ions from the solution until a new equilibrium is reached. The salt

580-487: A negligible or null systemic biological availability and they are designed to form stable complexes with Fe and Fe in the GIT and thus limiting the uptake of these ions and their long-term accumulation. Although this method has only a limited efficacy, unlike small-molecular chelators ( deferasirox , deferiprone , or deferoxamine ), such an approach may have only minor side effects in sub-chronic studies . Interestingly,

638-421: A result, references published before 1942 typically listed its melting point at around 1,800 °C (3,270 °F) when pure uranium metal actually melts at 1,132 °C (2,070 °F). The most effective way to purify uranium oxide in the laboratory was to take advantage of the fact that uranium nitrate is soluble in ether . Scaling this process up for industrial production was a dangerous proposition; ether

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696-483: A tenure track position. The position had already been filled, but the professor of chemistry there, W. L. Evans, knew that Winfred F. (Buck) Coover at Iowa State College in Ames, Iowa , had a position. "I wouldn't normally have chosen the place," Spedding later recalled, "but I was desperate. I thought: I can go there and build up physical chemistry and when jobs really open up I can go to another school." Spedding took up

754-414: Is a resin or polymer that acts as a medium for ion exchange , that is also known as an ionex . It is an insoluble matrix (or support structure) normally in the form of small (0.25–1.43 mm radius) microbeads , usually white or yellowish, fabricated from an organic polymer substrate. The beads are typically porous (with a specific size distribution that will affect its properties), providing

812-405: Is a weakly basic ion-exchange resin and is used to treat hypercholesterolemia . Cholestyramine is a strongly basic ion-exchange resin and is also used to treat hypercholesterolemia . Colestipol and cholestyramine are known as bile acid sequestrants . Ion-exchange resins are also used as excipients in pharmaceutical formulations such as tablets, capsules, gums, and suspensions. In these uses

870-480: Is also referred to as the Ames process. The study of rare earths was also advanced during World War II: synthetic plutonium was believed to be rare-earth-like, and it was assumed that knowledge of rare earths would assist in planning for and the study of transuranic elements; ion-exchange methods developed for actinide processing were forerunners to processing methods for rare-earth oxides; methods used for uranium were modified for plutonium , which were subsequently

928-407: Is passed through the resin, and trapped negative ions are flushed out, renewing the resin exchange capacity. Formula: R−H acidic The cation exchange method removes the hardness of water but induces acidity in it, which is further removed in the next stage of treatment of water by passing this acidic water through an anion exchange process . Reaction: Similar to anion resins, in cation resins

986-471: Is required for electronics, scientific experiments, production of superconductors, and nuclear industry, among others. Such water is produced using ion-exchange processes or combinations of membrane and ion-exchange methods. Ion-exchange processes are used to separate and purify metals , including separating uranium from plutonium and other actinides , including thorium ; and lanthanum , neodymium , ytterbium , samarium , lutetium , from each other and

1044-403: Is used to recharge an ion-exchange resin, which itself is used to soften the water. In this application, ion-exchange resins are used to remove poisonous (e.g. copper ) and hazardous metal (e.g. lead or cadmium ) ions from solution, replacing them with more innocuous ions, such as sodium and potassium , in the process cation and anion exchange resins are used to remove dissolved ions from

1102-537: The Army-Navy "E" Award for Excellence in Production on October 12, 1945, signifying 2.5 years of excellence in industrial production of metallic uranium as a vital war material. Iowa State University is unique among educational institutions to have received this award for outstanding service, an honor normally given to industry. The metallothermic reduction of anhydrous rare-earth fluorides to rare-earth metals

1160-526: The Manhattan Project was building up. At the University of Chicago, Arthur H. Compton established its Metallurgical Laboratory . Its mission was to build nuclear reactors to create plutonium that would be used in atomic bombs . For advice on assembling the laboratory's Chemistry Division, Compton, a physicist, turned to Herbert McCoy, who had considerable experience with isotopes and radioactive elements. McCoy recommended Spedding as an expert on

1218-555: The University of Michigan and University of California, Berkeley , Spedding became an assistant professor and head of the department of physical chemistry at Iowa State College in 1937. His efforts at building up the school were so successful that he would spend the rest of his career there, becoming a professor of chemistry in 1941, a professor of physics in 1950, a professor of metallurgy in 1962, and ultimately professor emeritus in 1973. He co-founded, along with Dr. Harley Wilhelm,

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1276-921: The William H. Nichols Award from the American Chemical Society in 1952, the James Douglas Gold Medal from the American Institute of Mining, Metallurgical, and Petroleum Engineers in 1961 and the Francis J. Clamer Medal from the Franklin Institute in 1969. He was nominated several times for the Nobel Prize in chemistry, but never won. An award called the Frank H. Spedding Award is presented at

1334-443: The magnesium and calcium ions found in hard water with sodium ions. When the resin is fresh, it contains sodium ions at its active sites. When in contact with a solution containing magnesium and calcium ions (but a low concentration of sodium ions), the magnesium and calcium ions preferentially migrate out of solution to the active sites on the resin, being replaced in solution by sodium ions. This process reaches equilibrium with

1392-904: The Ames Laboratory from its founding in 1947 until 1968. It was initially established on the grounds of Iowa State College. Permanent buildings were constructed that were opened in 1948 and 1950, and subsequently named Wilhelm Hall and Spedding Hall. Spedding was "universally acknowledged as one of the world’s foremost experts on the identification and separation of rare earths". He developed an ion-exchange method of separating and purifying rare earth elements using ion-exchange resins . He later used ion exchange to separate isotopes of individual elements, including hundreds of grams of almost pure nitrogen-15 . During his career, Spedding published over 260 peer-reviewed papers, and held 22 patents in his own name and jointly with others. Some 88 students received their Ph.D. degree under his supervision. After his retirement in 1972, he authored 60 books. He received

1450-738: The Institute for Atomic Research and the Ames Laboratory of the Atomic Energy Commission , and directed the Ames Laboratory from its founding in 1947 until 1968. Spedding developed an ion-exchange method of separating and purifying rare earth elements using ion-exchange resins , and later used ion exchange to separate isotopes of individual elements, including hundreds of grams of almost pure nitrogen-15 . He published over 250 peer-reviewed papers, and held 22 patents in his own name and jointly with others. Some 88 students received their Ph.D. degree under his supervision. Spedding

1508-788: The Pacific. His intention was to study in Germany under James Franck and Francis Simon , but they fled Germany after Adolf Hitler came to power in March 1933. Instead he went to the Cavendish Laboratory at the University of Cambridge in England, where he was welcomed by Ralph H. Fowler . Spedding worked with John Lennard-Jones , and attended lectures given by Max Born . He paid a visit to Niels Bohr in Copenhagen, and gave

1566-643: The annual Rare Earth Research Conference. Spedding suffered a stroke in November 1984, and was hospitalised, but sent home. He died suddenly on 15 December 1984, and was buried in the cemetery at Iowa State University. He was survived by his wife, daughter, and three grandchildren. His papers are housed in the Special Collections Department of Iowa State University. Ion-exchange resin An ion-exchange resin or ion-exchange polymer

1624-420: The assembly to 600 °C (1,112 °F); the large difference in density between slag and metal allowed complete separation in the liquid state, yielding slag-free metal. By July 1943, the production rate exceeded 130,000 pounds (59,000 kg) of uranium metal per month. Approximately 1000 tons of uranium ingots were produced at Ames before the process was transferred to industry. The Ames project received

1682-399: The basis for rare-earth metal preparation. Frank Spedding Frank Harold Spedding (22 October 1902 – 15 December 1984) was a Canadian-American chemist . He was a renowned expert on rare earth elements , and on extraction of metals from minerals. The uranium extraction process helped make it possible for the Manhattan Project to build the first atomic bombs . A graduate of

1740-489: The chemistry of the rare earths . These were expensive and hard to find, and generally available only in minute amounts. In 1933 he won the Irving Langmuir Award for most outstanding young chemist. The award came with a cash prize of $ 1,000. He borrowed money to travel to Chicago to collect it. While he was there, he was approached by a man offering several pounds of europium and samarium . His benefactor

1798-412: The contents of the container reacted violently, leaving a 35-gram ingot of pure uranium metal. The process was quickly scaled up; by October 1942 the "Ames Project" was producing metal at a rate of 100 pounds (45 kg) per week. The uranium tetrafluoride and magnesium were sealed in a refractory-lined reactor vessel, still referred to as a "bomb". The thermite reaction was initiated by furnace heating

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1856-446: The extraction of uranium-bearing water (grading as low as 0.05% U 3 O 8 ) through boreholes. The extracted uranium solution is then filtered through the resin beads. Through an ion-exchange process, the resin beads attract uranium from the solution. Uranium-loaded resins are then transported to a processing plant, where U 3 O 8 is separated from the resin beads, and yellowcake is produced. The resin beads can then be returned to

1914-429: The following features. The pore media of the resin particles is one of the most important parameters for the efficiency of the product. These pores make different functions depending on their sizes and are the main feature responsible for the mass transfer between phases making the whole ion exchange process possible. There are three main types of pore sizes: In this application, Ion-exchange resins are used to replace

1972-481: The head of the group responsible for fabricating the uranium, wanted a metal sphere the size of an orange for his experiments. With Westinghouse's process, it would have cost $ 200,000 and taken a year to produce. The other major problem was the purity of the uranium. Impurities could act as neutron poisons and prevent a nuclear reactor from working, but the uranium oxide that Fermi wanted for his experimental reactor contained unacceptably large amounts of impurities. As

2030-575: The highest-purity products. A very important case is the PUREX process (plutonium-uranium extraction process), which is used to separate the plutonium and the uranium from the spent fuel products from a nuclear reactor , and to be able to dispose of the waste products. Then, the plutonium and uranium are available for making nuclear-energy materials, such as new reactor fuel and nuclear weapons . Ion-exchange beads are also an essential component in in-situ leach uranium mining. In-situ recovery involves

2088-974: The ion-exchange facility, where they are reused. The ion-exchange process is also used to separate other sets of very similar chemical elements, such as zirconium and hafnium , which incidentally is also very important for the nuclear industry. Zirconium is practically transparent to free neutrons, used in building reactors, but hafnium is a very strong absorber of neutrons, used in reactor control rods . Ion exchange resins are used in organic synthesis , e.g. for esterification and hydrolysis . Being high surface area and insoluble, they are suitable for vapor-phase and liquid-phase reactions. Examples can be found where basic (OH -form) of ion exchange resins are used to neutralize of ammonium salts and convert quaternary ammonium halides to hydroxides. Acidic (H -form) ion exchange resins have been used as solid acid catalysts for scission of ether protecting groups. and for rearrangement reactions. Ion-exchange resins are used in

2146-545: The ion-exchange resin can have several different functions, including taste-masking, extended release, tablet disintegration, increased bioavailability , and improving the chemical stability of the active ingredients . Selective polymeric chelators have been proposed for maintenance therapy of some pathologies, where chronic ion accumulation occurs, such as Wilson disease (where copper accumulation occurs) or hereditary hemochromatosis ( iron overload , where iron accumulation occurs) These polymers or particles have

2204-470: The manufacture of fruit juices such as orange and cranberry juice, where they are used to remove bitter-tasting components and so improve the flavor. This allows tart or poorer-tasting fruit sources to be used for juice production. Ion-exchange resins are used in the manufacturing of sugar from various sources. They are used to help convert one type of sugar into another type of sugar, and to decolorize and purify sugar syrups. Ion-exchange resins are used in

2262-405: The manufacturing of pharmaceuticals, not only for catalyzing certain reactions, but also for isolating and purifying pharmaceutical active ingredients . Three ion-exchange resins, sodium polystyrene sulfonate , colestipol , and cholestyramine , are used as active ingredients . Sodium polystyrene sulfonate is a strongly acidic ion-exchange resin and is used to treat hyperkalemia . Colestipol

2320-444: The other lanthanides . There are two series of rare-earth metals , the lanthanides and the actinides. Members of each family have very similar chemical and physical properties. Ion exchange was for many years the only practical way to separate the rare earths in large quantities. This application was developed in the 1940s by Frank Spedding . Subsequently, solvent extraction has mostly supplanted use of ion-exchange resins except for

2378-427: The plutonium metallurgists. Fears that world supplies of uranium were limited led to experiments with thorium, which could be irradiated to produce fissile uranium-233 . A calcium reduction process was developed for thorium, and some 4,500 pounds (2,000 kg) was produced. After World War II, Spedding founded the Institute for Atomic Research and the Ames Laboratory of the Atomic Energy Commission . He directed

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2436-444: The position as assistant professor and head of the department of physical chemistry at Iowa State College in 1937. His efforts at building up the school were so successful that he would spend the rest of his career there, becoming a professor of chemistry in 1941, a professor of physics in 1950, a professor of metallurgy in 1962, and ultimately professor emeritus in 1973. By February 1942, the United States had entered World War II, and

2494-560: The rare earth elements, which were chemically similar to the actinide series that included uranium and plutonium. Compton asked Spedding to become the head of the Metallurgical Laboratory's Chemistry Division. Due to lack of space at the University of Chicago, Spedding proposed to organise part of the Chemistry Division at Iowa State College in Ames, where he had colleagues who were willing to help. It

2552-618: The regeneration involves the use of a strongly acidic solution, e.g. aqueous hydrochloric acid. During regeneration, the regenerant chemical passes through the resin and flushes out the trapped positive ions, renewing the resin exchange capacity. Formula: –NR 4 OH Often these are styrene – divinylbenzene copolymer resins that have quaternary ammonium cations as an integral part of the resin matrix. Reaction: Anion-exchange chromatography makes use of this principle to extract and purify materials from mixtures or solutions . Ion exchange resins are often described according to some of

2610-492: The same as the (incorrect) model advanced by Albert Ladenburg in 1869. At Gomberg's suggestion, Spedding applied to the University of California, Berkeley , to study for his doctorate under Gilbert N. Lewis . Gomberg wrote a recommendation so that Spedding was not only accepted, but given a teaching fellowship as well. Under Lewis's supervision, Spedding earned his Doctor of Philosophy (Ph.D.) in 1929, writing his thesis on "Line absorption spectra in solids at low temperatures in

2668-504: The simultaneous chelation of Fe and Fe increases the treatment efficacy. Anion exchange resins readily absorb CO 2 when dry and release it again when exposed to moisture. This makes them one of the most promising materials for direct carbon capture from ambient air, or direct air capture , since the moisture swing replaces the more energy-intensive temperature swing or pressure swing used with other sorbents. A prototype demonstrating this process has been developed by Klaus Lackner at

2726-443: The two most common resins used in the ion-exchange process. While anion resins attract negatively charged ions, cation resins attract positively charged ions. Formula: R-OH basic Anion resins may be either strongly or weakly basic. Strongly basic anion resins maintain their negative charge across a wide pH range, whereas weakly basic anion resins are neutralized at higher pH levels. Weakly basic resins do not maintain their charge at

2784-403: The two touched. To produce uranium metal, they tried reducing uranium oxide with hydrogen, but this did not work. They then investigated a process (now known as the Ames process ) originally developed by J. C. Goggins and others at the University of New Hampshire in 1926. This involved mixing uranium tetrachloride and calcium metal in a calcium oxide -lined steel pressure vessel (known as

2842-399: The uranium metal. At the time, it was produced in the form of a powder, and was highly pyrophoric . It could be pressed and sintered and stored in cans, but to be useful, it needed to be melted and cast. The Ames team found that molten uranium could be cast in a graphite container. Although graphite was known to react with uranium, this could be managed because the carbide formed only where

2900-723: The visible and ultraviolet regions of the spectrum". It was published that year in the Physical Review . Spedding's graduation coincided with the onset of the Great Depression , and jobs became hard to find. Spedding received a National Research Fellowship from 1930 to 1932, enabling him to stay at Berkeley and continue his research into the spectra of solids. While hiking in northern California, he met Ethel Annie MacFarlane, who shared his passion for camping, hiking and mountain climbing. Born in Winnipeg, Manitoba, she

2958-437: The water. Few ion-exchange resins remove chlorine or organic contaminants from water – this is usually done by using an activated charcoal filter mixed in with the resin. There are some ion-exchange resins that do remove organic ions, such as MIEX (magnetic ion-exchange) resins. Domestic water purification resin is not usually recharged – the resin is discarded when it can no longer be used. Water of highest purity

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3016-616: Was Herbert Newby McCoy , a retired chemistry professor from the University of Chicago , who had obtained a supply of these elements from the Lindsay Light and Chemical Company, where they were a byproduct of thorium production. A few weeks later, Spedding received a package in the mail containing jars of the metals. In 1934, Spedding was awarded a Guggenheim Fellowship , allowing him to study in Europe. To save money, Spedding and his wife travelled to Europe by heading westward across

3074-489: Was a graduate of the University of Saskatchewan and the University of Toronto , where she had earned a master's degree in history. When they met, she was teaching at Victoria High School in Victoria, British Columbia . They were married on 21 June 1931. They had a daughter, Elizabeth, who was born in 1939. From 1932 to 1934, Spedding worked for Lewis as a chemistry instructor. Around this time, he became interested in

3132-581: Was agreed that Spedding would spend half of each week in Ames, and half in Chicago. The first problem on the agenda was to find uranium for the nuclear reactor that Enrico Fermi was proposing to build. The only uranium metal available commercially was produced by the Westinghouse Electric and Manufacturing Company , using a photochemical process that produced ingots the size of a quarter that were sold for around $ 20 per gram. Edward Creutz ,

3190-478: Was born on 22 October 1902, in Hamilton, Ontario , Canada, the son of Howard Leslie Spedding and Mary Ann Elizabeth (Marshall) Spedding. Soon after he was born, the family moved to Michigan, and then Chicago. He became a naturalized U.S. citizen through his father. The family moved to Ann Arbor, Michigan , where his father worked as a photographer, in 1918. He entered the University of Michigan in 1920, receiving

3248-616: Was explosive, and a factory using large quantities was likely to blow up or burn down. Compton and Spedding turned to Mallinckrodt in Saint Louis, Missouri , which had experience with ether. Spedding went over the details with Mallinckrodt's chemical engineers, Henry V. Farr and John R. Ruhoff, on 17 April 1942. Within a few months, sixty tons of highly pure uranium oxide was produced. Spedding recruited two chemistry professors at Ames for his group there, Harley Wilhelm and I. B. Johns. Spedding and Wilhelm began looking for ways to create

3306-495: Was motivated by a fear of Nazi Germany 's developing nuclear weapons before the Allies . The process originally involved mixing powdered uranium tetrafluoride and powdered magnesium together. This mixture was placed inside an iron pipe that was welded shut on one side and capped shut on another side. This container, called a " bomb " by Spedding, was placed into a furnace. When heated to a temperature of 1,500 °C (2,730 °F),

3364-456: Was present at the University of Chicago on 2 December 1942, to witness the first controlled nuclear chain reaction in Fermi's Chicago Pile-1 . Throughout the war, the laboratory held regular information sessions known as "Speddinars". In addition to its work with uranium, the Ames Laboratory produced 437 pounds (198 kg) of extremely pure cerium for the cerium sulphide crucibles used by

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