Reply #108: Technetium: The first synthetic element; still being made by doctors.

[NNadir]

In my series of pedantic monologues :-) on the nature of fission products, the next element I would like to explore is Technetium.

I will cover this fascinating and widely used completely synthetic element much as I did above with cesium, giving a brief introduction followed by a section which will describe the dangers and problems associated with Technetium, followed by a section describing the mitigating factors and important technological.

My references will include a volume of the wonderful Analytical Chemistry of the Elements Series, a series of books written in the 1960's and 1970's by Russian Chemists and later translated into English by Israeli chemists. The particular volume is entitled "The Analytical Chemistry of Technetium, Promethium, Astatine and Francium." (Ann Arbor-Humphrey Science Publishers, 1970) I will refer to this fabulous text as ACTPAF.

An aside: This series has been out of print for years, but if you look hard enough you can always find a used copy of a particular volume you want to buy. I bought my first volume back in the early 80's. Last year my wife found a volume on line for the Analytical chemistry of Plutonium. It's wonderful to be loved.

I shall also be using the fourth edition of Cotton and Wilkinson's "Advanced Inorganic Chemistry" John Wiley 1980 (I need a newer addition, but I'll call this AC), and the National Research Council's "Nuclear Wastes" published by the National Academy Press. This work was published in 1996. (I'll call it Nus) I will also briefly refer to th 26th Edition of the Handbook of Chemistry and Physics, (HO CAP), which was released was current during 1942-1943, the years the Manhattan Project was under full steam.

Technetium was first known as "manganese" by Mendeleev, who predicted, although no such element was then known, that an element with atomic number 43 should exist and that it should have chemical properties very much like Manganese or perhaps like Rhenium, the very rare and exotic element that has limited use because of its high cost. After Mendeleev's elegant prediction, scientists lusted heartily after element 43. Some deluded themselves into thinking they had discovered it. Names like aluminum, Devin, lyceum, Nippon and Mariam were all proposed and even adopted. (My 1943 HO CAP calls element 43 Mariam. (ACTCAP pg 1)

Then the Italian Chemists Segre and Perrier bombarded molybdenum (element 42) with deuteron's. The product was unambiguously identified and ultimately the name Technetium was given in honor of the fact that this was the first artificial element ever made.

Technetium is a fission product, and is readily available at a metric ton scale from so called "nuclear waste." However much of the technetium in the environment comes from not from nuclear plants but from small portable cyclotrons in hospitals. These use the original reaction in which Mo-98 is bombarded with deuterons. The resultant technetium is then injected into a patient complexed variously for the purpose intended for its action. Of all the fission products it seems that technetium is the most widely used. Many hundreds of thousands of people have been treated with Technetium either by eating it or having it injected. It is also used to treat cancers by providing a targetable means of getting to bind to troublesome cells, like cancer cells.

More will follow.