124
The Last Resource
upper limit to the price that could be demanded for uranium when
low—grade resources are exploited.
The British investigations began several years ago when uranium
was in great demand. Various chemicals and resins were tested and
developed for their ability to absorb the uranium, present as a
complex compound in the sea—water. One resin developed at the
then National Chemical Laboratory (now part of the National
Physical Laboratory) actually achieved an extraction rate of one
gram of the uranium salt per gram of dry resin. Unfortunately, the
resin’s performance fell off rapidly as it became contaminated with
other constituents of the sea—water and ultimately it was discarded
in favour of titanium hydroxide—or more correctly hydrous titanium
oxide. The discovery that titanium oxide could take up appreciable
quantities of the uranium dissolved in sea—water led to prospective
studies of how the chemical might be used on a large scale. United
Kingdom Atomic Energy scientists devised a scheme involving a
tidal lagoon lined with beds of small particles coated with a thin
layer of titanium oxide. But before its completion, a world surplus
of uranium developed and it was therefore decided to abandon the
project.
More recently, it has become evident that the world’s supplies of
uranium will be under considerable pressure in the 1970s and the
British work has been revived. Considerable effort is now being
devoted to improving the preparation of the titanium oxide and to
_
devising some kind of inert carrier which will give better absorption
with less bulk. lnstead of the previous bed concept, the absorbent
material is being sandwiched between porous layers. In this way, a
compact unit consisting of alternating layers of absorbent and
support materials could be built, rather than using trays of absorbent
material spread out over the oor of What amounts to virtually the
open sea.
Finally, no section on the removal of chemicals from sea—water
would be complete without mention of the living chemical factories
within the marine environment; many marine animals and plants
have the ability to concentrate certain elements within their tissues.
Many of the chemicals involved—copper, iron and vanadium—
play some important role in the life processes of these creatures. For
example, the lobster needs copper in its blood just as we need iron
in ours. However, the role of some chemicals commonly accumulated is not always so certain and occasionally chemicals must be
The Last Resource
upper limit to the price that could be demanded for uranium when
low—grade resources are exploited.
The British investigations began several years ago when uranium
was in great demand. Various chemicals and resins were tested and
developed for their ability to absorb the uranium, present as a
complex compound in the sea—water. One resin developed at the
then National Chemical Laboratory (now part of the National
Physical Laboratory) actually achieved an extraction rate of one
gram of the uranium salt per gram of dry resin. Unfortunately, the
resin’s performance fell off rapidly as it became contaminated with
other constituents of the sea—water and ultimately it was discarded
in favour of titanium hydroxide—or more correctly hydrous titanium
oxide. The discovery that titanium oxide could take up appreciable
quantities of the uranium dissolved in sea—water led to prospective
studies of how the chemical might be used on a large scale. United
Kingdom Atomic Energy scientists devised a scheme involving a
tidal lagoon lined with beds of small particles coated with a thin
layer of titanium oxide. But before its completion, a world surplus
of uranium developed and it was therefore decided to abandon the
project.
More recently, it has become evident that the world’s supplies of
uranium will be under considerable pressure in the 1970s and the
British work has been revived. Considerable effort is now being
devoted to improving the preparation of the titanium oxide and to
_
devising some kind of inert carrier which will give better absorption
with less bulk. lnstead of the previous bed concept, the absorbent
material is being sandwiched between porous layers. In this way, a
compact unit consisting of alternating layers of absorbent and
support materials could be built, rather than using trays of absorbent
material spread out over the oor of What amounts to virtually the
open sea.
Finally, no section on the removal of chemicals from sea—water
would be complete without mention of the living chemical factories
within the marine environment; many marine animals and plants
have the ability to concentrate certain elements within their tissues.
Many of the chemicals involved—copper, iron and vanadium—
play some important role in the life processes of these creatures. For
example, the lobster needs copper in its blood just as we need iron
in ours. However, the role of some chemicals commonly accumulated is not always so certain and occasionally chemicals must be