Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
- SPECIFICATION
Heavy metal soaps such as cobalt, lead, vanadium,
zirconiurn, nickel and other nalphthena~es are widely used as
accelerators or driers to speed up the dr~ing and curing of
5 oil~based varnishes and ~paints. They are also used as additives
in plastics, in flame-retardant compositions, silicones, and fuels.
Cerium soaps are lL~own to have drying action but have
not come into wide use because they are expensi~e to prelpare.
Recently ~ey also haYe been proposed as additives in fuels~
10 flame-retardant compositions and plastics and silicones and have
other potential applications. The cerium soaps described in ~e
. literabure are cerous soaps. To o~r knowledge there is only one
description in ~e literature of ceric soa~s or ~eir prepara~ion9and
~at is by B. I,. K~sotra et al Transition Metal Chemistry, 1,
15 158-161 (19q6), who state that a good deal of work has be~n carried out
on cerous carbo2~ylates 'rl3ut there is no reference in ~e literature
to the preparation of ceric carb~xylat~s"~ The paper deals wi~
the prepa~a~ion a~d chara~terization of ceric carbo~{yla~es by
~e reaction of ~I2CeCl6 with HCO~7 a mixture o~ (MeCC))20,EtCO~,
20 n-PrCO~ and ~CO~I7 re~pecti~ely:
YI2CeCl~ RCOOH , C~e(OO~R)Cl~ ~{ H20 -~ 3HCl
The carboxylates prepared by thîs me~ud contain ~ree
chlorine atoms,as shown above. l~ttempts by Kalsotra et al to
l~le~ ceric~carbo~ylates by ~e reaction of dipyridinium ceric
~q~
~' ~
~2~2~
he7~chk-ride (C5H6N)~CeCl6 with sodium salts of fatty acids,
analogous to the preparation of ceric cyclopentadienyl and ceric
indenyl compounds,failed.
There are however cerium soaps on ~e market ~at are
5 actually a mixture of cerous and ceric carbo2~ylates; ~ese are
cerium naF~enates con~inin~ from 30~C to 50% ceric na~enate.
The method for ~eir preparation has not been divulged; ~ey are
being manufactured in France.
The me~od used for preparing hea~ry metal soaps depends
10 on t~e reacti~rity of the particular metal or derivatives thereof.
The processes most commonly used are:
(a) anion e~ch~n~e7 displacing an inorganic anion by
carboxylate anion, carried out by allding a base to a well agita~ed
aqueous $olution of a metal inorganic salt in ~e presence of a
15 solution of the desired carboxylic acid in an ~o~l-iate wa~er-
immiscible sol~ent;
(b) precipitation of ~e metal soap ~om a~Lueous ~oltl~?o~q
of ~he metal salts with alkali soaps;
(c) fusion of metal oxides7 hyd~o~ides or salts wi~ organic
20 acids or esters; and
(~ direct reaction of finely-divided metals in heated
organic acids.
Process-wise, me~ods (a) and (b~ are the easiest to
carry out, alld are usually also the most economical. T~ey are
:~J
~%~
applicable to cerium as well as to many other metals. Any a~aila~l~
soluble common cerous salt such as cerou~ nitra~e or chloride
ccm be used in method (a) to prepare ~erous soaps. Theoretically,
by analog~ to cerous~ soaps, water-soluble ceric ammonium nitrate
5 or ceric sulfate can be used to prepare ceric soaps. There is
no litera~ure reEerence showing that this has ever been done,
however. The pro~lem is ~at ceric ammonium nitrate and ceric
sulfate, the only commercially available wa~er-soluble ceric salts~
are prohibitively e}~?ensive. This is perhaps one reason why only
10 cerous alld no ceric soaps are described in ~e literature.
.... ..
When ~e solid metal soap is desired, process (b) îs
most suitable, and is applicable to cerium. Any availabl~ soluble
cerium salt such as cerous nitrate or chloride ca~ be used to
prepa~e cerous soaps in solid form. While t~eoretically t~e water-
15 solul~le ceric salts such as ceric ammonium nitra~e or ceric sulfatecould be used, an~ perhaps are used i~ preparing ~e available
mixed cerous/ceric naph~enates, ceric ~oaps are ei~el~ liquids
or waxy substanc~s, and would be hard to isolate.from ~e rea~ti~n
mixture.
M~eover, i~ is also prohibiti~ely expensive to prepare
ceric soaps aecording to metllo~l ~b)5, beca~e ~e only a~ailable
~olllhle inol~ganic ceric salts are ~e e~pensi~e ceric ammonium
nitra~e and eeric sulfate.
~2~2~
Ceric hydroxide is of low reactiYity and solubility, and not
suitable for ei~er n~e~nd (a) or (b).
In a~cordance wi~ ~e present invention, ~e use of
e~pensive ceric ammonium nitrate or ceric sulfa~e is avoided by
5 sta:r~ing wi~ ~e correspon~ing cerous soap, o~ritli ~i ng ~e cerous
soap to ~e ceric soap with aqueolls hydrogell pero}cide.
The problems in h?/n~li n~ and recovery of ceric soap from
~e rea~tion mixture are eliminated by carrying out ~e o~ida~ion
wi~h aqueous hydrogen peroxide ln a two-phase system com~ising
10 a~ aqueous phase of hydrngen peroxide ha~ing a p~I of at least 6 and
an organic phase comprisîng a solnti~n of cerous ca~bo~late
in a water-immiscible hydrocarbon solvent at a tempera~ure ~ which
the reaction proceeds but below ~he temperature of rapid decompo-
sitio~ of hydrogen peroxide~ lhereby converting cerous to ceric ion
15 and formirlg a ~olution o cerîc carb~?~ylate in ~e hydroca~on
solvent. Then, when reaction is complete, ~e reaction ml~ture
is heated at a tempel dl.Ul e at which any ceric ~hydrogen pe~o~ide
complexes are decomposed, and ~e organic -phaLse ~en separated
from the a~Lueous phase o~ ~e reaction mixture. The ceric carboxyl-
20 ate is normally used in ~e ~olution as prepared and can 'be res~overedfrom the organic phase by any desired procedure, such a5 ~)y sol~ent
distillation at low temperature ~d pressure.
~,i '
~2~2~
The reaction is ~eoretically capable of qualltit~tively
corlYerting cerous $o ceric carbox~Tla~e. It is not however neces5a~y
for most commercial purposes to effect a complete conversion. The
r~tio o Ce*~ produced over ~e total cerium present can be varied
5 as desired from l~c up to ~ ~c -
The usefulness of only 1~c Ce~4 in Ce~3 carbo~ylate solutions
can be appreciated by ~e une~pected reduced viscosity of ~e Ce~3/Ce~4
carboxyla~e solution which o~erwise could pose problems. Bo~
cerous arld ceric carbo~late are chemically equivalen:t as a sourcè
10 ~ cerium for rea~tions where cerium is desired, as în driers or
accelel~lo~s. Howe~el~ organic solvent solutions of cerlc ca~boxyl-
ates ha~re a much lower viscosity ~an organîc solvent solutîons oP
cerous carbo~ylates at like cerium concentrations, and Mle reductîon
in vîscosity is already marked when ~e total cerium is 1~c ceric.
~L5 It îs ~u~ suitable fol many purposes to convert as lîttle as 1~c of
cerous c0rîum to ceric. How~e~ ~ ît îs normally desira1~1e t~
collYert from 30~ZC to 60% and preferably fro~m 50~ to 95% of ~e
cerou~ to cerîc cel ium, for applîcatîons where hîgher Ce~ content
is s~ught.
The cerolls caxboxylate can be used directly as a star$ing
ma$erial, insolutiollin~ewater-îmmîsciblehydroca~bonsolva~
a~d ~e aqueous hydrogen pero2~ide solutîon ha~ing a p~I o a~ lea~ 6
combined wi~ ~is solution în forming ~e two-phase reaetion system.
The cerous carbo~la~e ca~ also be formed in ~Itu from a cerous
2~1
compound and a carbo~la$e compound~ :~or example, an inorganlc
cero~s salt sllch as cerous nitrate or cerous sulfate, and ~e
carbo~;ylic acid wi~ alkali, or ~e carboxylic acid salt, in which
case alkali is not necessary. The cerous carbo~rla~e forms in situ
5 as a~ i.ntermediate, but in any event ~e product is ceric sarbo~ylate,
in solution in ~e solvent.
Whell cerous carboxylate is used as a starting material7
~e procedure is referred to herein as Me~hod 1, and when a cerous
coml~ound a~d a carboxylate compound are used as a sta~ting
10 material, ~e procedure is leferled to herein as Me~od 11. These
two procedures, while similar in principle7 are ra~er different in
e~ecution, process~wise7 and t~ere~le will be considered separ~ely.
Met~od 1, sinc~ it invol~es cerous carbo~ylate as ~he
sta~ing material, can also inclllde ~e prepara~ion of cerous car~
15 bo2~ylate from an ~norganic cerous salt and a ca:rboxylic acid, and
in ~is ~ve~ ~e reactîoxl mi~ure can be used directly in the
hydrogen pe3~oxide o~ tion~ wi~out separation of cerous ca~boxylate
sol~ion from t~ aqueous layer. This is ~e most economical way to
apply lhe proce~s, a~d i~ therefore L~e~e- ~e~.
YVhile ~e most practical ~d economical way to produce ~e
ceric soaps is by integra~ing all o~idation step in ~e process of
m~kin~ cerous soaps, ~e o~idation can also be applied t~` a solution
of any cerous soap in a hydrocarbon sol~ent by adding an aqueous
solution of hydrogen peroxide. For in~t~n~e~ any commercial
cerous carbox~rlate solution can be mixed wi~ an aqueous solution
~ hydrogen peroxide9 whereupon ~e oxidation will take place.
Excess carboxylic acid, pre~erably as ~e ammonium or.alkali metal
salt, can also be added.
5 Method ~ -
For syn~lesis of cerous carboxylate, method (a) above canbe used. A base such as all~li metal, Io~ e~ample sodium or
po~assium, llydrOxide or ammonium hydroxide is added to a two-
p~ase system co~t~inin~ water-immiscible solvent alld a well-
10 agi~ed aqueous-solution of a solu~le cerous salt such as cerous
nitra~e, cerou~ chloride, or cerous ~~ te a~d the correspo~ n~
carbo2ylic acid, all in a~ least stoichiom~ ric amount but preferably
USiIlD a~ excess of ~e acid. Cerous carbo~ylate obtained in ~his
nner is ~hen e~ra~:te~ from the aqueous reaction mi~re wi~ a
15 water-immiscible hydrocarbon sol~rent in which it is solwble~ ~d
which ad~ tageously can be present a~ tihe time ~ addition oiE ~e
base, ~us forming a two-phase system alrea~y in ~is stage, or ~t
ffle en~ of ~e preeipitation o cerous carbo~late from ~e a~Lueous
~ase~ The orga~ic pllase of cerous carbox~late di~solved in hydro-
20~carbon so.lvent can ~en be separa~ed flom *lLe aq~leous phase, but
~is i; not necessary.
Three moles of ca~bo~rlic acid is stoichiDmetrically
required per n~ole of Ce~3 salt to make ~e Ce~3 ~bo~lalte. Theo-
retically~ one e:x~ra mole of acid is needed if all Ce+3 is to be
;~
converted to Ce~4 in the form of ceric carboxylate. The fact is t~at
~e oxid~tion proceeds well at less than the theoretical amoun~ of
acid. This is an indication that the Ce~4 carboxylate produced by
~e process contains o~er functions such as--~H or o~er bondings.
~he base t~at is used in carrying the me~od (a) ~r prepal-
lng cerollS so~ps can be sodium or potassium hydroxide, carbonate
or bicarbonate7 or am:monium hydro~ide. The amount of base is
important7 at least ~e stoichiometric amount for ~e cerium î~
reqlired in order to comrert all cerium into sol~ent-soluble cerium
cal~boxylate, ~nd to adjust ~iH to at least 6, a~l preferably higher
~an 7, prior to ~e oxidation wi~ hydrogen peroxide.
~Iydrogen peroxide is added as all aqueous solution ~hortly
after the addition of ~e base has been completed7 and prior to the
separatioll of ~e two layers. P;referably, t~e pH of ~e reaction
~5 mi~ture`prior to ~e H202 a~ldition is abave 6. While ~e order oP
combining ~e reactallts can be va;rietl7 the addition of H20z should
be last, for better results.
The reaction mi~ture is kept under vigorouS agitation while
~e aqueous solution o h~rogen pero~ide iS being added. The ~ -
2û reaction begins a~ l~oom ~mp~alw-e and ~e reaction mixture r~pidly .
de~elops a reddish d-drk bl~own color. ~ydrogen peroxide is lmown
to form colored water-soluble comrlP~s wi~ inorganic ions an~
probably ~e same is occurring in ~is case wit~ ceric ioll. In ~e
process of the inventio:n, ~e ce:rium carboxyla~e/hydrogen perog~de
25 system forms a dark colored organic solven:t so~ution dlle ~ the
complex, which upon heating decomposes by releasing H2O2. There-
fore, a~ter a short period of time during which some of the hydrogen
pero~ide oxidizes Ce+3 to Ce~4 and ~e rest becomes immobilized in
forming the said complex, ~e temperature of ~e reaction mixture is
brought to from 60 to 75C, to destro~ ceric-~1202 comple~es, where-
up~n the color li~tens to a p~rmanellt yellow orange, indicating ~heir
decomposition.
The ~moun~ of hydrog~n peroxide added can ~rary considerably,
according to l~e extent desired of ~e conversion OI cerous to ceric9
10 from 5~O to abo~e 90%. A 100% conversion is difficult to obtain as
~her~ appea;rs to be som~ degree of reduction o Ce~ to Ce~3, which
in some cases, depending on ~e carbo~yla~e ion, is responsible or a
drop in. and l~us a limitation upon the rn~ m Ce~ content. S:mall
O~ .S ~f H2O2 can also be used, ~vhich will result in a lesser
15 conversion of cerous to ceric. A small con~rersion, ra~glng from
1% to 5%~ could be desira~le for some applic~ions. The degree of
co~lvel~;ion depends also on lhe na~ure of ~e carbo~rlic acid alld
~e` impurities l?reseng. The degree of consrersion of cerous to ceric
îs g~rea~er in ~e case of neodecanoic a~id ~an for naph~enic acid,
20 fo~
To achie~e a high conversion of ce~us to ceric9 two
more ~ tio~s of hydrogen pero~cide followed each time by a heating~
~ooling sequence to decompose ceric-H202 complexes may be required,
dependîng upon ~e car~oxyla~e anion. In ~e case of some carbo~ tes,
9 '
~f!
,,~
one addition of H20~ is enou~h to raise ceric to over 90~c. Wi~
o~er carboxylates, in order to reach 90~c, two or ~ree addi~ions
of :H202 are needed, as for in~t~nce wi~ ceric naph~enate. One
reason for ~is is that ~e mi~ture sold as naphthenic acid is itself
5 oxidi~able by ceric, and ~is secondary reaction consumes ceric~
collverting it to cerous and holding down the ceric content.
lhe amount of carbo~ylic acid as already in~ te~ should
be more than stoichiometrically required for ~e cerous soap, i. e. 9
3 moles per g atom of cerium. The corresponding cexic soap madè
10 in accordance wi~ ~is inve~ltion may contain some OH or other
bonding, which is acceptable foI- many of ~e applic~lons. ~ite
often, cerous soap solutions contain an e~ccess of ~e corresponding
carboxylic acid. It is preferable to use about 4 moles of carbo~ylis
acid, so as to have ~e a~noun~ stoichiometrically r~uired hr the
15 ceric soàp ~hat is to be made. More ~an 4 moles o~ acid can be
used7 if desired.
Me~od II
In accordance with ~is me~odS cerous ion in the reaction
medium is oxidized by addin~ an a~ueous solution of hydrogen
pero2~ide:
(1) into an aqueous solution of alkali carbo~ylate and prior
to the addition of the aqueous solution of cerous salt, or
(2) into an aqueous solution of the inorganic cerous salt
solution ei~er (a) prior $o ~e mixing wlth ~e alkali carbo~ylate
~olution9 or ~b) at a con~rolled rate during ~e rni7~in~ with the alkali
lû carbo~rlate solution. The presence OI a~ organic solvent during th~
reaction is preferable7 to e:~ract the ceric soap as it is formed.
The amou~ of hydroge.n peroxide is-not critical, and can
vary rom less ~an ~e stoichiometric amount required to a large
e~cess. Norrnally7 an excess is preerred; because of the te~ çnc.y
15 of the cerlc iOIl to form comple~es wi~ ~e H2O2. After $he miging
of t~e alkali carbo~Tlate and the cerous salt has been completed9
more hydrogen peroxide can be added to increaæe ~e ceric content,
lf desired. It masr be necessary in some cases to he~t ~e solutiorl to
~rom. 65 to ~0C to destroy the colored ceri~H202 comple~c9 prior
20 to adding more Et202.
The addition of H22 iS preferably done a~ room tempera~ure,
but ~e temperat~re can ~:~tend up to 7ûC, wil~ l~e penaltsr ~f
a correspo~in~ly less ef~icient reaction, because of loss of H202.
A~ ~e son~lusion of the reaction7 ~e reaction mi2~ure îs heatesl
11
at 60 to 75 C7 to decompose the ceric-~2O2 complex, and destroy
all H O
eXcess 2 2-
In both methods, the yield can be improYed by z2~tracting
the aqueous phase with organic solverlt, and combining ~is with the
5 organic phase, when ~e ceric carbo~ylate is sparsely soluble in
water.
The process of the inYention can be used for conversion
of any cerous soap whish can be dissolYed in a wa~er-immiscible
hydro~arbon sol~reIlt, in a sufficient amoun~ to permit ~e reaction
10 to proceed. The proces~ is of particular appllcatioll and commercial
interest to the preparation of cel ic naphthenate, ceric 2-e~ylhe~oate9
and ceric n~decanoa~e, which are therefore preferred, but it can OI
course be applied for the preparation of any desired ceric carboxylate
salt of any ali`phatic or cycloaliphatic satura:~ed or lln~:~hlrated
15 carboxylic acid or mixture ~ereoI ha~ing from about seven to ~bout
eighteell carbon atoms, starting from ~e corresponding cerous
carboxylate. ~ .
E~emplary carboxylic acids- p:ro~riding carbo~ylate anion
include cap~ic, 2-et~yl hexoic" capryrlc~ ric, myristic9 stearic~
20 palmi~ic, oleic, linoleic, linolenic, ricinoleic? na~llL~enic, rnethyl
cyclohe:~anoic, mel~yl cyclohexenoic, cyclohep~anoic, and t~e fatty
aci~ mi~tures derived from na~ral fats arld oils, such as COCOllU~ oil
fatty acids, tallow fatty acids~ lard fat~v acids~ corn oil fatty acids,
lin~eed oil fatty acids, tUIlg oil fatty acids, rapeseed oil fatt~ acids~
25 cottonseed oll fatty acids, ~Eish oil fatty asids, soya~ean oîl fatty
acids aIld sa~flowerseed oil fatty a~ids.
12
'~
~2~
If ~e cerous carbo~ylate is not a~ailable, the process of the
invention is combined with its preparation as a first ~tep, using a
wa~er~soluble cerous salt such as cerous ammonium nitrate, cerous
nitrate, cerous sulate or cerous aceta:te with ~e ree carboxylic
acid in ~e stoichiometrically equi~alent a~ount as staxting materials.
Arly water-immiscible liquid hydrocarbon solvent in which
~e cerous soap can be dissolved to form ~e organic ~hase of ~e
reaction mi~ture can be employed, includm~ alipha$ic, cycloaiiphatic
and arom~tic hydrocarbon solvents having from about six to about
10 fou~teen carbon atoms such as, for e2~ample, petroleum e~ers7
which are composed of para~finic hydrocarbons? cycloaliphatic
hydrocarbons, and mixtures ~ereof 7 he~ane, hepta~e9 octane,
no~ne~ decane, dodecane7 tetradecane, cyclohexan~, cyclohep~ane,
cyclope~t~ne~ cyclooctane, cyclohexene, cyclohep~ene, cyclooctene,
15 benæene, toluene, p-cymene, psuedo-cumene? ~he ~rlene~,
m:lesit~lene, ethylbenzene, 172,3-trimethylbenæene9 tetrame~yl-
. benzene7 propylbenzene, isopropylbenzene, ~e dipropylbe~ enesand the diisopropylbenzenes.
13
"`:
2~3
The following Exarnples in t~e opinion of the inventors
:represe~ preferred embodiments of ~e invent;on.
~MPLE 1
In a four-necked three-liter rourld-bottom ~lask equipped
5 with a rapid-stirring mech~nic~l stirrer~ thermometer, condenser
aIld additioll funnel were placed 146. 8 g of aqueolls cerous nitrate
solution (23. 86~C cerous), 0. ~50 mole~ 190 g neodeca~oic acid"
1. 011 moles, a~d 358. 9 g Amsco 140 (a petroleum ether sol~en~ -
composed o~ 92~ZC nap}l~enic ~y~rocarbons a~d ~8~c paraffinic
10 hydloca~bons). ~ueous ~mmnnhlm hydroxide, 1035 g, 1.006 moles,
was added dropwise to the well agi~ated mixture of neo~ec~noic
acid, cerous nitrate solution and petroleum ether. Followin~
compl~hoIl of the a~ldition of ~e arnmonil~m hydroxide over a two
hour period, 26. 0 g o 30% a~ueous hydro~en pero~ide, 0. 23 mole~
15 was added i~ an equ~l weigllt, 2~ g~ o water. The re~ction mi~re
turned a deep brown, ~s3 a~ter forty minu~eæ of rea~tion lleating was
beguh to 7~0C, to decompose ~e Ce~4~ comi le~es~ and contirlued
f~r an af1ditional twenty nlinutes. In 1~e ~ou~se oE ~le decomposition,
~e Teacti~ migture turlled orange, ~en bright yellow. After cooling?
- ~o ~e rea~tion mix~ure separated into two layersj a clear orange upper
orgallic layer and a~ almost clear yellow lower ~ueous layer.
The layers wlere separated; and washed wi~ 200 g of
water. The organic layer was diluted with 300 g hexane, arld the
~ ater azeotroped out, aIter which ~e hexane was distilled. T~e
25 Ce~4 in ~he residue ~581. 9 g) was 9D~ OI the total cerium.
- 1
* Trademark
... ~,~
~20~
- EX~MPLE 2
To ~e reactiorl vessel described in Example 1 was added
29. 4 g aqueous cerous nitra~e solution ass~yir~ 23. 79% Ce (0. 05
mole), 38. 0 g neodecarloic acid tO. 20 mole~ d 72. 6 g 'Amsco 140.' TM
The ~ueous arnmonium h~dlo~ide 167. 2 g (0.16 mole) was added
dropwise to ~e well-a~itated mixture OI neo~canoic acld, aqueous
cerous nitrate and petroleum e~er solvent o~rer ten minutes. There
was ~hen added ~e a~ueous hydrogen peroxide,, 5. 2 g, 30% H2O2,
toge~er WLEh all egual weight~ 5. 2 g,~f water. The ~ix~are turned
10 daxl~ brown, and the tempel ~lul e began to rise. ~ter Porl;y
mimlteS of reaction, heating was begun to 78C.ovex~ l~en mim
to decompose the (; e~4/H202 comple~; whereupon ~e reactio
mixture became orange-yellow, and ~en yellow.
The reaction mixtur~ was cooled to 40C ~d ~e mixture
15 separated into two layers, ~s~ upuer pe~rl~;c~nt y~llow organic laye
and a lower sli~htly yellow ~queous l~yer.
Tlhe wet hexane s~ ic)n w~s ~x~ ot~ope~l ~ry. The cool
solutlon was ~ilte~ rou~hlSupeir~ellfilf:er aid .~nd t~e ca~e w~hed
wi~ he~ne. The collected orange shiny solid ceric nPo~c~n~e
20 was 0. 26 g. ~fter di.still~ion of the hex~ne flom the organic layer,
119~ 6 g of product was reco~ered7 assaying 5. 09% Ce~4.
* Trademark
:E~AMPL:E 3
Tn a reaction flask was added 176. 4 g a~ueous cerous nitrate
solution assaying 23. 79% cerium (0. 3 mole), 169. 2 g neodecanoic
acid (0.9 mole), and 208.8 g Amsco 140, and stirringbegun. Aqlueous
ammonium hydro}cide, 1044~4 g (1. 009 moles) was a~ded dropwise
to ~e well-agitated mixture over a period of one hour at 22 to 23C.
A~ ~e conclusion of ~is period ~e ~I was 7. Hydro~en pe~oxide
was ~en a~ded (0.2 mole, as 30% solul;ion) toge~er with an e~ual
am~unt of w~ter o~rer a few minutes. The mi~*are was allowed to
10 react for twenty minutes7 and then t~e tempel~lu~e was brought to
70C and held ~ere for twe~ty minutes to decompose the C~t'lH202
complex. The reaction mixture was then cooled to 90C~ whereupon
it separated into two l~yers; an upper organic layer, which was
viscous and ta~, in ~e form of an em~ io~7 and a lower~ ueous
15 layex~ whLch was colorless and clear.
To ~e mix~ure was added 100 g OI he2~ane. The layers were
~en separated. The ~queous layer was e~ctra~ted wi~ tw~o portions
o~ 130 g each of hexane ~d ~e organic wa~hings were then combined
wlth ~e orgallic layer~ ~e water azeotroped out from ~e orgallic
20 layer, a~ter which ~e hexane was ~i.qtillefl off. The residual 443.1 g
~msco solution was assayed at 1. 3'3~ Ce~.
~6
,
EXAMPLE 4
Into a 500 ml round-bottom flask equi~ped wi~ a rapid
stirrer and a droppillg furmel was charged 29. 4 g aqueous cerous
nitrate solution assaying 23. 86G/c Ce (0. 05 mole~, 29. 3 g 2-e~ylhexoic
acid (0. 20 mole) and 81 g of Arnsco 140. Aque~us ammonium
h~d, .,~Lde solution, 205. 7 g, ~ 6~c NH3~ was then added dropYvise
over forty nnulutes. At ~e end of ~e addition the p~I of the rea~tion
mi~ure was 7. 5. The orga~ic layer was s~i~htly viscous, and ~e
aqueous laye~ was clear. There was then added 5. 22 g hydrogen
~o peroxide, 30~C H2Oz~ wi~ vigorous stirringO A dar~ brown color
formed almost at once, and ~e organic layer became lessviscous.
Stirring was contimled for fortg-five min~tes. Upon completion
~ t;his reaction time, heating to 70Ct was then begun, to destroy t~e
unreacted Ce~4/H2O2 comple~es. Af~er 75C was re~ch~, tihis
.
15 temperature was m~int~;ned ~o~ thirty ~imltesO The darkbro~1vn
col~ disappeared? resulting in an orange? sl tly yellow oil
and an a~ueous layer.
... ... .. . . .... .. _ . . . ..................................... . . . .. .. ..
The reaction mi~ure was cooled with ice to 20C~ There
was ~en added 5 g ~nmo~i~m lly~ ide ~ollltiQn~ followed by
20 1. 53 g 30% hydrogen peroxide solutioql, -and ~e reaction mii~ture
was ~n stirr~d for thirty ~nimlt~sO The mixture was l~en heated
to 70C and held at fflis temperature for thirty minutes.
The re~ction mL~re was ~en cooled to 20C, ~ which
point ~e pH was 7. 0. There was ~en a~ded l. 53 g hydrogen peroxLde
25 as a 30~c H2O2 .sollltio~- The reaction mixture was ~tirred for one
17 ~
2~
hour, and then heating to 70C begun. The reaction mixture was
held at 72C for ~irty miJQutes, and ~en cooled to 20C in an ice
water bath.
I'he organic layer was separated from the aqueous layer,
5 and washed with two portions of 25 g each of w~er. The weight of
~e organic laye~ was 110. Q g~ There was ~en added 100 g hexane,
and ref~ n~ begun to remo~e the water. Xexane was then removed
under 40 to 80 m m at a pottenn~elalule of 42 to 62C. The product
was a ye~ow-green oil, 114.6 g, 5.17% Ce~
1~
18
EX~MPLE 5
In the reaction system of Example ~ ~ere was placed
29. 9; g aqueous cerous nitrate solution assaying 23 . 86~C cerium
(G. 05 mole), 50. 5 g (0. 20 mole) naph~enic acid and 59. 3 g Amsco 140.
5 Stirring was begun9 alld aqueous ammonium hyd-l o~ide solution 170. O g
(O. 17~ mole) was then added dropwise over a period of ~r~ mi~utes.
Ne~ was a~lded 3.1 g lH202, 30~c H202 solution (0. 0327 mole) to ~e
Yigorollsly stirr~d reactiorl mi~re. A dark ~rown color formed.
Stirring was co~ti mle/1 for fo:rl;y-fi~re mimltes and ~e mixture then
10 heated to 75CC to destroy ~e Ce~4/hydrogen peroxide com~31e~e.~7
and held a~ ~is temperature for ~irty minu~es. The mix~re was
thell cooled in a wa~er/ice bath to 20C,w~ereupon it separated into
two layers. The organic layer wa~s rem~ed, lO0 g he~ne added7
and ~e mixhlre ~he~ heated to reflux. :~efln~ E was contimle~
5 azeotroping out ~e wa~er. The rem?/ining hexane was ~hen distilled
under low pressure, yielding an oily material which was dried o~er
S~ill~ .S llf~e. Total cerium b~ alysis was 3 . 07~/c, of which ~~c
or 2.15% was Ce~4. Weight 21~ g.
æ~
lh~XAMPL~: 6
Molar
(~harges Amount Mwt. ~c Moles ~atio
Ce(NO3)3 solution 29. 4 g 140.12 23. 86 O. 050(Ce) 1. 00
Ce~3
.A~lSCO ld~O 61. ~i g 1232 g/
fflole Ce
Naph~enic acid 48.2 g 240.8 0.200 4.0
NaOH solution 156 ml 40 O. 980N 0.153 3.06
H22 solution 4.8 g 34 32.7 00046 1,84
~ 500 ml three-necl~l round bottomed flask was equipped
with mer.h~niGal stirrer, ~ermometer~ ~I electrode and dropping
unnel.
The cerium solution, r~ihthenir. acid a~d Amseo 140 were
15 combined a;nd stirred vigorously while ~e NaOX sol~ion was added
o~er 2. 5 hours. The pero2dde was a~lded in ~ equal volume of
wa~er o~ter ive minutes causing a d~ep re~ eolor. The mixture was
- let ~irri~g for t~venty hours. The mi~ture was heated to qOC
for one~alf hour9 cooled a~d ~en ~e organic l~yer was assayed to
20 give 73% ce:ric.
~0
:,
~L~
~AMPLE '7
Charges Amoullt Mwt. ~c - Mola~ Ratio
Ce(NO3)3 solutiorl 29.4 g 140. :12 23.86 Ce
Amsco 140 81.0 g ---
Octoic acid 29.3 g :l44.2 98.3
NaOH solution 16~ ml ~0 0.980 N 3.24
H2O2 solution 4.8 g 34 32. 9 1.84
A 500 ml ~ree~necked round bottomed flask was equi;pped
with m~h~ al stirrer, ~ermometer, EiEI electrode and dropping
10 ~nnel.
The cerlum s~ tion, octoic acid alld Amsco were combined
alld stirred vigol~ously while ~e N~C~H solution was ~dded o~rer two
hour~
The hy~ o~,el~ peroxide sollltion (4. 8 ~) was added and 1 he
15 mi~re was sltirred seventeen hours. The mi~blre was hea~ed to
70C ~Ol~ one-ha~ hour, cooled, ~en assayed to give 70% ceric.
A seso~d portio~ f 3, 4 g pero~ide was a~lded followed by avernight
stirring aIld ~hort heating to give 91~C ceric- The two layers spllit
very q.uickly a~d cleanly.
21
EX,AMPLE 8
There were mi~ed 2. 0 g cerous e~yl hexoate solid with
50. 0 g of Amsco 1~0 and stirred until appro~imately 80~C dissolYed.
H ~O2 solutioll (0. 38 g o a 10~C ~ueous solution) was added and the
5 mi~ re stirred to obtain a red-orange solution which was allowed
to stand for two hours and ~en placed in a 70~C ba~ for ~irty
minllte,S to decompose Ce~2O2 comple}~es. The color became lighter,
whereupon ~e mi~bare was allowed to cool an~ settle.
Titration wi~ ferrous ~mmo~ m sulfate solution indicated
10 24% Ce~4 total cerium.
22
~2~2~
E~AMPLE 9
There was added 2. 9~6 g cerous naph~enate solid moles to
50. 0 g Amsco 140 axld ~en stirred and heated to 60C to ol~tain
a solution which was cooled to 25C. H2O2 solution (0. 58 g of a 10~c
5 a~Lueous solution) was added and the mixture stlrred for fi~e minutes,
placed in a 70C ba~ for ~irt~ mltes and allowed to cobl to
25C. The upper layer was sampled and titrated wi~ ferrous
ammonium sulfate, indicating 46. 2~c Ce~ ~otal cerlum.
23
., ~,
EXAMPLE 10
2-ethyl he~oic acid (l. 0 g~ was added to 2 g of solid cerous
2~thyl he;~:oate. Upon heating and addition of 50 g of Amsco all went
in~o solu$ion. HydIogen p~roxide (10% solution) 0. 60 g was added
5 at room temperature, and ater five minutes ~e re~ctLon was heated
to 70C and ~en cooled, A seconcl portion o 0. 6 g f H2O2 was
added, a~ room temperat;lre and heated again to 70C. ~alysis
~n~ic~ 24~C o~ tl~tal ~ was c~ric.
24
E~AMPLE 11
TherQ was placed 4. 4 g 2-ethyl hexoic acid in a flask.
There were added 4. 0 g of 30~C NaO~I solution, followed by 0. 57 g
of 30~ H2O2 solution, stirred and 5. 9 g Ce(NO3)3 solution added to
5 obtain an orange solution which solidified ater three rninutes. 10. 5 g
Amsco 1~0 was added to make an a~ueous solution, whic~ was
stirl~ed for five mixlutes and ~en placed in a 70C bath for t~irty
mirlutes. The solutioll w~s allowed to cool and org~nis l~yers
sar~pled for titration.
w~w~kTcOe~ralcce- 12~C
:Repea~ed additions of H202 increased ~e amount o ceric.
~o~ ~æ~
:EXA~PLE 12
Charges Wt. Assa~ 100 37C Moles
Cerous 2-e~ylhe~oate 2.0 24.0 0.48 g Ce 0.0034
2-:E~ylhe~oic acid 1.0 98.3 0.9030 0.0070
Amsco 140 50.0 50.0
H2O2 1. 16 1b 0. 1~66 0. 0034
Cerous 2~e~ylhe2~oate alld 2-ethyJhexoic acid were
combine~. 50. 0 g Amsco 140 and 0. 58 g E22 ~10~C W/W) were
added, stirred f ive minutes and hea~ed to 70C over thirty
10 minutes a~d ~en cooled.
W/W~C~e- 46. 4%.
O. 58 g H22 '~D~C w/w) wa~ added a ~econd tirne, stirred
five minutes, and ~eated at 70C over ~irf:y mimlte,s and t~en
cooled. -
w/w'3~ ~teallCe = 67. 8%.
26
, ~ .