Monel nickel-copper alloy withstands cor rosive fluoride a t t a c k in t h e s e s e r i e s -
connected towers for separating Β-10 and B - l l isotopes found in natural boron.
Hooker "divorces" boron isotopes in unusual 350-foot, 6-tower, Monel fractionator gets 3 pounds per day of precious neutron-absorbing The towers shown above are part of a six-tower fractionating system that may be the world's most effective. It is located in the AEC's Boron-10 plant, designed and constructed by Singmaster & Breyer and operated by Hooker Electrochemical Co. In 350 feet of total height (they're connected in series) they enrich a dimethyl ether-boron trifluoride complex containing 18.8% B-10 to one containing 92% of this isotope. Strangely, the separation of the B-10 and B-ll constituents does not depend on volatility. Instead it de pends on a difference in the rates of
boron-ΙΟ
association and dissociation of the DME-BF., complex. The lighter B-10 compound comes off in the liquid bottoms and the heavier B-ll com pound in the vapor tops. Corrosion potential is high
With fluorides at 105°C, and with the inevitable trace moisture present in a system of this type, a high cor rosion potential is established. For this reason, from the point where boron trifluoride enters the system via a Monel nickel-copper al loy reducing valve, most equipment is made of Monel* nickel-copper alloy
. . . tanks, columns, re-boilers, con densers, pumps, valves, piping. Columns are filled with protruded Monel alloy packing Monel alloy is highly resistant to the fluoride corrosion that is so often a problem in preparing isotopes and nuclear fuels. What's more, it has the high strength and fabricating prop erties needed for pressure vessels and allied equipment. For technical assistance with your own corrosion problems, call on Inco's Development and Besearch Division. •Registered trademark
The International Nickel Co., Inc. 67 Wall Street , Ι Ν Ο ^ New York 5, Ν. Υ.
INCO NICKEL ALLOYS VOL. 50, NO. 5 · MAY 1958
27 A