Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
1 03~
The present inventioD relates to A ~atrix con~isting of
algae, ~Dd a method of making such Eatrix a~ well 88 to the
applic~tion of the matrix for obta~ning fro~ sea water urani-
u~ di~olved iD ~ea w~ter
Numerou~ att0~pts hRve been ~ade to obtain uranium from
sea w ter beca w e the ~a water contains a practically unli~it-
~d ~upply of ur~Dium The heretofore known method~ for obtain-
iDg ur~nium fro~ ~ea w ter ar~ b~-d either on the principle of
extraction in couDt-rcurrent or count~rflow, vn the cheDical
precipitation, addition, on the ~xch~ng~ of ion8 or on flota-
tioD With 11 h~retofore known m-thods of the type involved,
it W~8, how~v-r, n~c~ ry to o ploy ch-~ical sub~tAnces Thi~ -
ha~ tb- dr wb ck that in ~-n-r~l gre-t quantiti-~ of che~icals
w re ne-ded 90 tbat th- cost~ for tbe coc~u~pti~n of the re~-
pect~e u-te~ial~ were r~th~r hl~h and tbat pollution of the
~urrou~ding~ occurr-d ~hic~ could aot b- eli~i~ated at ~ll or
ooly t v ry hi~h xp-n~ nothor drawbac~ inher-nt to tbe~e
~no~o _ thod~ con~iJt~ iD th-t a co~id-rabl~ consu ption of
n-r~y wa~ n-c-J~ary to practic- the~- h r-tofore k~own D~thod~
b c~uJe Ithou~h ur niuo i~ pr-~ nt in ~ea wat-r in great quaD-
titi-~, it occur-, ho~ ver, i~ J~ water iD ~ very low co~con-
tr tion
It iJ, th-r for-, D obj-ct of th- pr-~nt inv-ntion to
pro~d- atrix ~Dd to rploy th- J-U- for obtainine ura~u~
froa J~ ~ater without polluti~e th Jurround~g- ~nd without
U~iD~ a~y ~nersy which requir-~ reL~tively high ~xpense~
The~- object~ hsve been realiz-d accordi~g to the present
i~vention by ue ns of for ing the above rentio~ed ~atrix from
~.o3t~6s
a uranium compatible mutant suitable for receiving uranium dissolved in sea
water. In this connection it has proved particularly advantageous to employ
a matrix which is formed of single-celled green algae, but it is to be under-
stood that also multi-celled algae are usable in this connection.
For the sake of completeness, it may be added that it is known
that mutants of one-celled green algae are uranium compatible. It has also
been speculated that such algae might be suitable for obtaining uranium from
sea water, but heretofore no teaching has been disclosed how to go about
technically to realize this speculation.
This invention seeks to provide a method of preparing a matrix
comprising in combination mutants for single-cell green algae to be cultivated
compatible with uranium and suitable for extracting uranium dissolved in sea
water, which includes the steps of: introducing the algae into a sterilized
nutrient solution adjusted to an acidity of pH 6, and formed of 3.8 grams sea
salt, 0.03 grams of NH4N03 as well as 5 ml earth extracts in 100 ml water,
introducing in steps into the thus obtained solution uranium in the form of
uranylnitrate until the quantity of uranium has been enriched to 250 mg/l,
subjecting the algae to x-ray radiation at a dose of approximately 50 kR,
pouring the algae onto agar plates formed by employing a solution of 3.8 grams
sea salt and 0.03 grams of NH4N03 and 5 ml earth extracts in 100 ml water,
inoculating the thus forming colonies individually and further cultivating
the same in a nutrient solution formed by the solution of 3.8 grams sea salt
and 0.03 grams NH4N03 and 5 ml earth extracts in 100 ml water.
A preferred method of practicing the present invention consists
in that the matrix is arranged in a filter cage with at least two screen-
shaped walls which permit sea water to pass through but which are non-perme-
able for the above mentioned mutants. The mesh size of the screen walls em-
ployed for the filter cages must be less than the size of the cells of the
mutants forming the matrix. Therefore, the cell size of the algae forming
the matrix should be around from 50 to 100 ~.
ia38168
For obtaining uranium compatible algae, green algae are in con-
formity with the present invention introduced into a solution with a high
uranium concentration which solution contains sea water or the essential
components of sea water whereupon the thus obtained solution with the algae
therein is subjected to radiation by x-rays. The remaining algae are sown
on a uranium containing nutritive substratum or nutrient medium, and the
surviving cultures are taken off therefrom and are kept in pure sea water
for forming a mass culture.
In order to obtain uranium from sea water, a flow of sea water
is passed through the matrix formed according to the invention.
According to another modification according to the present
invention for the obtainment of uranium from sea water, the matrix arranged
in a filter cage is provided in an area of the sea which is subjected to
the tides so that the flows or currents caused by the low tide and high tide
are passed through filter cages surrounding the matrix. The total cross
section of the matrix should in such an instance be approximately 100 square
meters in order that with the flow velocity in the sea water as it is caused
on an average by the tides generally in the vicinity of the shore will
generate a through-flow rate through the cage of 106t sea water per day.
The separation of
' .~
the ur~hium fro~ the ~atrix i~ carried out by oe~n~ of one of
the custo~ary ~ethod# for in3tBno8 by extr~ction by mea~s of
tributylphosphate.
~xample
A~ ~tartiD~ material, unic~lled ~reen algae were used
which ~er~ derived fro~ the sea water of the M~diterr~ean
(L~E-cQla/Spain). Theso al~ae ~or~ introduc-d into a nutri~t
solution for~d by a ~olutloD of 3.8 ~r~Ds ~a salt ~nd 0.03
~ra~s NH4N03 in 100D1 water. Thi~ 801ution Wa8 pre~iously
~terilized aDd ~ub~equ~ntly wa~ ~djusted to an acidity of pH6.
Furth~r ore, 5~1 e~rth extracts ~re add~d to s~id solution.
Sub~equ-Dtly, uraDiu~ in the for of uranylnitrste w~ atded
to the solutioD while the ddition of ur ~yl~itr te was i~-
cr a~ed iD step~ up to a que~tity of 250~s/1 ur~niu~ The
al~ae _ d~ co-patible ~ith ur niu in thi~ w~y wcre then ub-
j ct-d to radiation by X-ray~, th~ do~e of w~ick was ~ppro~i-
~tely 50~ at 120kV a~d 18~ During this radiatio~, ~n alu~-
iDUa filt-r ha~in~ a thic~D-~ of 1 7 _ wa~ e~ployed Thn
gr -n algae tr at-d in thi~ w~y w~re ~ub~equently poured onto
~r-pL~t-~ ~hich contaiDed tbe bov~ ~ Dtioaed nutri-nt solu-
tion as w-ll as 500~U/1 ur~niuu Ths colonies thus for~cd were
intlvidually inocuLated The thus obtainod ~in~le-celled cul-
tur-s wer- t~ted ~- to their c~p~bility of receiving ur~niu~
To thi- end, th- abo~- ~oDtioDed fon~ed coloDie~ are ~ain iD-
-rted into nutrieDt Jolution of the abov- ~ ntion d cooposi-
tlon ~Dd re further cultivat-d iD this ~anner ~he culture~
of ur niur co patible one-c~ d al~a- were tested as to ability
to ta~- on or pic~ up uraniuo by in~ertin~ the ~a~e iDto ~-~
~38 ~ ~ ~
water which contain~d a co~centratio~ of less ~han 6ppb ur~ni-
um. Thi~ solutioD was cha~od daily for ten dByJ. It wa~
fouod that the c~ntrifu~ed-off al~e hsd a ura~ium conteDt
which i~ higher by a f~ctor of 1,000 thhn the uraniu~ co~t~nt
of the mediu~ i~to which thR ~raniu~ co~patible al~ae were in-
sert-d.
It i8, of course, to be understood thet the pre~ent i~en-
tion i~, by DO ~eaD8~ li~ited to the Jpecif~c ~Xa~P1Q ~et forth
a~o~e, but al~o co~prise~ any ~odificatiQns withi~ the ~cope
of the pp~ded claims.
It ~ay al80 be mentionod that by "oar~h extr~ct" is to be
~ under~tood treatod hu~us soil. Mor- ~p~cifically, lk of humu~
~oil ha~ b--n ~ixed with 1 liter of water aad subjected to a
t-~per ture of 100C. for two hour~, ~hereupon the water i~
filtered off. The thus obtai~ed ~ub~tance i~ the earth extr~ct
invol~ed.
With resard to thc proc-~s stop of ~ubj-ctiag the al~ae
to ~n X-ray radiati , the radiation ti~e ~ay vary fro~ a few
J conds to a f-w hour~, d-p-DdiS on the al~a~ and oth~r cir-
CU 8tanc-~ involved. Tho 8aiD point i~ that th~ total do~e
of X-ray radiaticn ad~iDist-r-d to the lgae i~ 50kR or about
50k~.
