CA2103796A1 - Stabilizing composition for s-substituted aldehydes, process for stabilizing aldehydes and stabilized aldehydes - Google Patents
Stabilizing composition for s-substituted aldehydes, process for stabilizing aldehydes and stabilized aldehydesInfo
- Publication number
- CA2103796A1 CA2103796A1 CA 2103796 CA2103796A CA2103796A1 CA 2103796 A1 CA2103796 A1 CA 2103796A1 CA 2103796 CA2103796 CA 2103796 CA 2103796 A CA2103796 A CA 2103796A CA 2103796 A1 CA2103796 A1 CA 2103796A1
- Authority
- CA
- Canada
- Prior art keywords
- aldehydes
- stabilizing
- mtpa
- substituted
- aldehyde
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C319/00—Preparation of thiols, sulfides, hydropolysulfides or polysulfides
- C07C319/26—Separation; Purification; Stabilisation; Use of additives
Abstract
This invention relates to a stabilizing composition for S-substituted aldehydes with general formula (I) having 4-15 carbon atoms, where: R1 = C1-C5 alkyl, C6-C9 aryl, furfuryl, benzyl; R2 = H, R1; R3 = H, R1, characterized by the fact that it is based on a prototropic agent (A) in association with an 02 abstracting agent (B). The components are selected among: (A) aromatic or heterocyclic aromatic amines, such as pyridine, dimethylaniline, quinoline, etc., alcanolamines or non-aromatic cyclic amines, such as triethanolamine, N-methylmorpholine, etc., lactams, such as N-methyl pyrrolidone, etc. (B) substituted phenols or hydroquinones, such as p-t-butyl phenol, BHT, etc., acid or unsaturated antioxidant agents, as ascorbic acid or beta-carotene. The amount indicated of said composition is 500-1000 ppm, preferably 1000 ppm, and the (A)/(B) molar ratio is comprised between 5/95 and 50/50. The process for stabilizing S-substituted aldehydes provides for addition to the stabilizing composition to an aldehyde containing up to 300 ppm of water at a stabilization temperature of up to 50 ·C. The temperature so which the aldehyde is subjected in the stabilization process is 25-100 ·C, and the aldehydes may be in contact with carbon steel. The proposed (A)/(B) composition is efficient to stabilize aldehyde with a certain amount of H20 in the presence of carbon steel and at a 25-100 ·C temperature.
Description
W093/13059 PCTiBR92/~20 ~- 21~379~
STABILIZING COMPOSITION FOR S-SUBSTITUTED ALDEHYDES.
PROCE5S FO~ ~TABILl~ING ALDEHYDES AND STABILI~ED
AL~EHYDES
TECHNICAL FIELD
This inventi~n relateæ to a sta~ilizing compo~ition for S-suhfitituted aldehydes, such a5 ~eta-methyl-thio-propionio aldehyde (MTPA)~ in order to prevent deterioration of thi~. product under v~rying temper~ture and moistur0 conditions, including in the presence or a~sence of c~r~on steel. It further concerns a cta~ilization proce~s using the proposed st~bilizing composition, ~s well a& stabiIi2ed aldehyde.
~ACKG~OUN~ A~T
Aldehydes fiub~ected to storage usually a~sor~e 07, setting off a series of reactions characteri2ing product degradation. The state of the art has alre~dy propo~ed many altern~tives for sta~ilizing aldehydefit such as addition of:
a) aromatic or aliphatic amin~fi, fiuch as pyridine, quinoline, dialkylamines, prefera~ly ir an amount of ~ ppm, 1ncluding for the case o f M~PA .
WO93/13059 PCT/BR92/0~20 21`~3796 B4ck ln 192g, U.S. p~.tent 1736747 already propo~ed the st~bilizAt~on of aldehyde~ against oxid~tion by addlng 1.2-d~minoeth~n~, for in~tance~
dl(phen~lamlno)ethane, in an ~mount o~ 0.25-1.0%. Pat~nt JP 7j 32963 disclo~eæ MTPA st~bili2~t.ion ~y adding pyridine, quinoline, collidine or lutidine, in an ~mont of 0.1X. Another Japane~e patent, JP 49116017 ~Nov/27/74) provid-es for MTPA stabilization by means of N,N-dialkylaniline in an amount of 0.2X. Finally, in lg45 U.5. patent 23~1771 quinolines, particularly ~u~stituted dihydroquinones, ar~ propo~.ecl as antioxidants for rubber~, glues, petroleum and derivbtes lgasoline, aldehydes).
b) alkanolamines ~5 Authors ~agarin E., and H.M., in reference Perfumer, 46 (7), 33-5, 1'~44, cite the u~-e of alkanolamine& for stabilizing aldehyde&. They also &uggest for the same purpo&e the use of alkyl-substituted phenols. Patent SU
56862g reveals formaldehyde stabilization for preventing formation of formic acid and methanol ~y adding triethanolamine in the amount of O.Z5-~.5X.
c) unsaturated tetrasubstituted compounds Such stabilizers are cited in GB ~75Z85 t1952).
d) composition based on a phenolic compound ~phenol&, naphtholc-, etc.) and ar amine ~pyridine~ picoline, W093/1~9 PCT/BR92/00020 2 1~
lutldlne~ collldine1 quinol~ne or mlxture~ thereo~, preferably A cy~tem ba4ed on 4-methoxyphenol and pyridlne at 1000 ppm, usefuL ~or S-sub~t~tuted aldehydes CUch ~ MTPA, whlch compo~ltLon i~ de4cribed in U.~.
patent 4546~05 IPl ~341502) of PENWALT CORP.
Stabilizing composltions proposed in the state of the art have many drawbacks, such as the fact that they contain toxic amines and a relatively low ~oiling point before aldehydes, and such compositions may even ~0 interfere in the distillation to which the product i5 ~u~ected ~efore being used in synthetic routes. The extent of such interference will depend on thé relativ0 moleaular weigbt ~and boiling point) rangeF. of product and sta~ilizer.
~ISCLOSURE OF INVENTION
.
Broadly speaking, aldehyde decomposition is due to absorption of 02, followed by auto-oxidation, aldol condensations and in some cases thermal decompositions.
The main mechanisms of decomposition of S-fiubstituted aldehydes are:
a) auto-oxidation by way of absorption of 02 and cont~ct with metal, witt, propagation by free radicals.
,_ 2~037~1~
~) ~ldol cond~ns~tlon~ In ~cid medlum; cycll~
trLmerizot~ons And polymerizations.
c~ thermal decomposition reactlons ~ncath~lyzed or c~tholyzed b~ metals. In the c~se of non-stabillzed MTPA, there occuræ form~tion of methyl mercapt~n, acrolein, water and ethylene from MTPA itself and decompoæition products thereof.
d) nucleophilic additions and-substitution~. In the ca~e of MTPA, this occurs from the decomposition product methyl mercapt~n, originating mercapt31s and thioesters.
e) dec~rbonylations, i.~ lIminatIon of CO with ~orm~tion of non-carbonylic organic sulfides.
These five types of reactions probably act jointly and by a chain process justify the great capacity for ~bsorption of oxygen displayed by 5-substituted aldehydes, such as MTPA, as compared with other carbonylic compounds, which makes it recommendable as antioxidant for vegetable oils ~Journal Amer. Oil Chem.
Soc., 1977, 54, p. 4-7). It should ~e stressed that oxygen, cont~ct with met~ls and the thermal factor, either separately or ~ointiy, are decisive causes for decomposition of 5-substituted aldehydes.
The æchemes below show, for example, possible routes for MTPA decompocition, based on gas chromatography analysec WO 93/13059 PCr/BR92~00020 2 ~ ~ 3 7 9 ~
coupled with mas~ :;pectror~copy, under thæ followiny condition:~.
WO 93/13059 PCltBR92/00020 21037~ 6 SCHEME I
~Hc~cc~c~cHc~ ~c ~H2 ,p 1 ~D~rn-r 1-0 ¦~xxxv~ln SC~ 200 ¦ H'SC~CiH~ ¦ ~0 ~H2 ~X~ /
~ 16 i uW-~S ~W~OC ~O 11 o-y H
H;~C~C-C~ N~C9H CHz CH-C~H , H CH,C112SC~
/ l~XVIII~ I
_~ _ ~ ~ I H~C~IC112H~C~H l n~lol-I I H C5H2cH2c;~o3~H ~\ ~
l L~Wz~ ,.x.L~ I \
\ _ l ~ .-lllU _ H3CscHz~ H2C~ H ,cll2cH2 IV~ I UW~ 10~ ,C~
m~tl~ Wn~Z~ --;~ _ _ \ CH35CHz C 2~ J~cH CH~SC~
I.IW~ 1!12 ~CH, /3C9H /¦ \~lr,l j lXVl,LXlX ~ XXI
~VI _ CHS5CHzCHzC;H / 1 ~2l~t ~ m~
lLXXV11_ I J / ~; ;HzCH21 ~ ~ ZOiJ o NXXXI
--~ ----~--H2C; -C" ¦ , 1--H~C~CH2CH~-CCHzCHzSCH~
, ~ I H3C5CH2CHzC ' \H~ / E ~ I ~ , o~ o ~VIII) -HzO / l \ ¦ CH35CHzC~12C~ SC~12CI~CH~¦
\--l ICH2--CHZ 1 \~IW~222 lXXXVI) ~_ ~ ~ ¦ H!~c~cHzcHzc~ l II~CS~ ~
~ ~ , I
120 ¦ ._ L L~ ~scl , CU~cO;~oH ~ ~
--1~ 'H ~ ~ H' ~0 C~SCH~ j,\
-H20 ¦ H3CSH lLXXlV) I \ ~_.. __ ~ C~ ~ I ~SC~
/~IX~ lX) ~Xl) WO 93/130~9 PCI`/BR92/00020 6A 2~ 0373~
H 0~xxxv~xxxa~
H~CSCH2CH2C~C-C;~ -Co . ~2~ CH~ I .H~CSH
UW- 1~0 1.2~20 ~c I"~c.c-c~'"
~_ ~ H /
I l~WIII~ , I ~--~V.I60 H~,CSCH~,CH2CH-C,H CH~C~H C~ ~ I C~-~O~p~ 111 j~,w-~lz lc~ I;CH3 C ~ Hl ~o I~TP~. H5C ~!~ CH H
I W~1711 S~CH~
H~C~
hlW~2011 SCH~ ¦
xv1 ~2 I~Y UW. IC2 /-H~C~ H~C~CH2CH2~HC~2XH~¦
~W.I90 "~
~C5CH2CH2CH ,;~¦ H 0 ~ m~bl~ ~O-Z¦
IXXV~XX 1111 ~ I TPI~ HO H
~H~C CHC H 7 ~v~
¦ H2i Cl ~ 5CH
112~ ,C-CH2~C~ /
I~UV) ,1 ~ CII I
~ i Xll) 21~379b ~ ' t -H~ ' ', ~ "'' .
Y1~2Yl N~C# ~ ~¦ HS 5 H
1~1~0 ~o1/ 1~2~0 ' ~
H2C~CH-CH-CH C~ ¦ ~1 ~Sc~.a~2~H-cN~
~XXIv~X)~I~ ~I~LIJll ~SH~ ~ ' ~Vlll A
~H~CSH
H3CSH ~XII.XX) SCI~ ¦
1 2C CH HCHZCH~ ~1 .' ~ IU~
lXlX~xxxl x~
H C~c~l-c~ci-~H
iMW-220 SCH~
h~C5H l WO 93/13059 PCI`/BRg2/00020 6C ~ 7 ~ ~
t,=~,~, ~ ~ ' ' . .
WO93J130~9 PCT/BR92J00020 A.1.~ - O J ABSORPTION AN~ AUTO-OY.lDATIOM: formation of an addition compound between 02 and MTPA, which is regulated by dissolution of O~ in org~nic medium. From that point onwards., eith~r MTPA pero:cyacid is formed, which le~.~. to MTPA acid, or the reaction evolves. to form~tion of fr~e r~dicals., as mercaptide, which in turn leads, to formation of disulfides and heavy compounds.
WO 93/13059 PCr/BR92/00020 2~37~
., ~ W.... Vl ~n ~ ~ 3 ~ ~ o .
~ ws s ~ ^ , ~ s o o ~0 ~" c S S ~ S ~ \ ¦
~ Q, s \ \ S
o 3 _ ~ ~
/1 1 i\o ~ ,, ~
o,~
~o ~0 ,~
n S ". O ,~!
o ~ ~, ~ ~ O. n ~ æ s Q n ~ c~ o X ~
2103 7~u ., A.~.2 - ALDOL CONDENSATIONS IN AClD MEDlUM: reactlons catalyzed by ~clds, favored by the sta~illty of MTPA
enolic form. Dimers, trimers and poly~ers are formed:
_ WO 93/13059 PCr/BW2/00020 w ~3~
t o~ ~ ~
o .. .
,S ~=
> X ~ T
T_ ~--O
r ~ --n--~-- n O
~ /~
1 T~ O
¦ ~ x . ", o O i I ~
O ~ 'S ~
n _ O
. . ~
Il"
o 10 ~ ~I
o ~
X ",I
~ ~ O ,~ ~
O ~
2~ ~ 37 9 b A.1.3 - THERMAL DECOMPOSITION: reactions of MTPA and decomposition products thereof, significant at a ~ 65~C
temperature. The presence of metals accelerates this type of reaction. This thermal decomposition displaces the equilibrium of A.1.1 and A.1.~ and causes reaction~
of the A.1.4 type, due to release of methyl mercaptan in the organic medium.
WO 93/13059 PCI~/BR92~00020 21~3~
n ;r~ 5 D
~ I J
~ S
.. ,.t , S ~S o ~c .. ~
,, o --n--~ ~2 ~0 ~I Xn ~0~ ~= N n =
NS "~ ~ ln ~S ~ ¦
o' ;~
STABILIZING COMPOSITION FOR S-SUBSTITUTED ALDEHYDES.
PROCE5S FO~ ~TABILl~ING ALDEHYDES AND STABILI~ED
AL~EHYDES
TECHNICAL FIELD
This inventi~n relateæ to a sta~ilizing compo~ition for S-suhfitituted aldehydes, such a5 ~eta-methyl-thio-propionio aldehyde (MTPA)~ in order to prevent deterioration of thi~. product under v~rying temper~ture and moistur0 conditions, including in the presence or a~sence of c~r~on steel. It further concerns a cta~ilization proce~s using the proposed st~bilizing composition, ~s well a& stabiIi2ed aldehyde.
~ACKG~OUN~ A~T
Aldehydes fiub~ected to storage usually a~sor~e 07, setting off a series of reactions characteri2ing product degradation. The state of the art has alre~dy propo~ed many altern~tives for sta~ilizing aldehydefit such as addition of:
a) aromatic or aliphatic amin~fi, fiuch as pyridine, quinoline, dialkylamines, prefera~ly ir an amount of ~ ppm, 1ncluding for the case o f M~PA .
WO93/13059 PCT/BR92/0~20 21`~3796 B4ck ln 192g, U.S. p~.tent 1736747 already propo~ed the st~bilizAt~on of aldehyde~ against oxid~tion by addlng 1.2-d~minoeth~n~, for in~tance~
dl(phen~lamlno)ethane, in an ~mount o~ 0.25-1.0%. Pat~nt JP 7j 32963 disclo~eæ MTPA st~bili2~t.ion ~y adding pyridine, quinoline, collidine or lutidine, in an ~mont of 0.1X. Another Japane~e patent, JP 49116017 ~Nov/27/74) provid-es for MTPA stabilization by means of N,N-dialkylaniline in an amount of 0.2X. Finally, in lg45 U.5. patent 23~1771 quinolines, particularly ~u~stituted dihydroquinones, ar~ propo~.ecl as antioxidants for rubber~, glues, petroleum and derivbtes lgasoline, aldehydes).
b) alkanolamines ~5 Authors ~agarin E., and H.M., in reference Perfumer, 46 (7), 33-5, 1'~44, cite the u~-e of alkanolamine& for stabilizing aldehyde&. They also &uggest for the same purpo&e the use of alkyl-substituted phenols. Patent SU
56862g reveals formaldehyde stabilization for preventing formation of formic acid and methanol ~y adding triethanolamine in the amount of O.Z5-~.5X.
c) unsaturated tetrasubstituted compounds Such stabilizers are cited in GB ~75Z85 t1952).
d) composition based on a phenolic compound ~phenol&, naphtholc-, etc.) and ar amine ~pyridine~ picoline, W093/1~9 PCT/BR92/00020 2 1~
lutldlne~ collldine1 quinol~ne or mlxture~ thereo~, preferably A cy~tem ba4ed on 4-methoxyphenol and pyridlne at 1000 ppm, usefuL ~or S-sub~t~tuted aldehydes CUch ~ MTPA, whlch compo~ltLon i~ de4cribed in U.~.
patent 4546~05 IPl ~341502) of PENWALT CORP.
Stabilizing composltions proposed in the state of the art have many drawbacks, such as the fact that they contain toxic amines and a relatively low ~oiling point before aldehydes, and such compositions may even ~0 interfere in the distillation to which the product i5 ~u~ected ~efore being used in synthetic routes. The extent of such interference will depend on thé relativ0 moleaular weigbt ~and boiling point) rangeF. of product and sta~ilizer.
~ISCLOSURE OF INVENTION
.
Broadly speaking, aldehyde decomposition is due to absorption of 02, followed by auto-oxidation, aldol condensations and in some cases thermal decompositions.
The main mechanisms of decomposition of S-fiubstituted aldehydes are:
a) auto-oxidation by way of absorption of 02 and cont~ct with metal, witt, propagation by free radicals.
,_ 2~037~1~
~) ~ldol cond~ns~tlon~ In ~cid medlum; cycll~
trLmerizot~ons And polymerizations.
c~ thermal decomposition reactlons ~ncath~lyzed or c~tholyzed b~ metals. In the c~se of non-stabillzed MTPA, there occuræ form~tion of methyl mercapt~n, acrolein, water and ethylene from MTPA itself and decompoæition products thereof.
d) nucleophilic additions and-substitution~. In the ca~e of MTPA, this occurs from the decomposition product methyl mercapt~n, originating mercapt31s and thioesters.
e) dec~rbonylations, i.~ lIminatIon of CO with ~orm~tion of non-carbonylic organic sulfides.
These five types of reactions probably act jointly and by a chain process justify the great capacity for ~bsorption of oxygen displayed by 5-substituted aldehydes, such as MTPA, as compared with other carbonylic compounds, which makes it recommendable as antioxidant for vegetable oils ~Journal Amer. Oil Chem.
Soc., 1977, 54, p. 4-7). It should ~e stressed that oxygen, cont~ct with met~ls and the thermal factor, either separately or ~ointiy, are decisive causes for decomposition of 5-substituted aldehydes.
The æchemes below show, for example, possible routes for MTPA decompocition, based on gas chromatography analysec WO 93/13059 PCr/BR92~00020 2 ~ ~ 3 7 9 ~
coupled with mas~ :;pectror~copy, under thæ followiny condition:~.
WO 93/13059 PCltBR92/00020 21037~ 6 SCHEME I
~Hc~cc~c~cHc~ ~c ~H2 ,p 1 ~D~rn-r 1-0 ¦~xxxv~ln SC~ 200 ¦ H'SC~CiH~ ¦ ~0 ~H2 ~X~ /
~ 16 i uW-~S ~W~OC ~O 11 o-y H
H;~C~C-C~ N~C9H CHz CH-C~H , H CH,C112SC~
/ l~XVIII~ I
_~ _ ~ ~ I H~C~IC112H~C~H l n~lol-I I H C5H2cH2c;~o3~H ~\ ~
l L~Wz~ ,.x.L~ I \
\ _ l ~ .-lllU _ H3CscHz~ H2C~ H ,cll2cH2 IV~ I UW~ 10~ ,C~
m~tl~ Wn~Z~ --;~ _ _ \ CH35CHz C 2~ J~cH CH~SC~
I.IW~ 1!12 ~CH, /3C9H /¦ \~lr,l j lXVl,LXlX ~ XXI
~VI _ CHS5CHzCHzC;H / 1 ~2l~t ~ m~
lLXXV11_ I J / ~; ;HzCH21 ~ ~ ZOiJ o NXXXI
--~ ----~--H2C; -C" ¦ , 1--H~C~CH2CH~-CCHzCHzSCH~
, ~ I H3C5CH2CHzC ' \H~ / E ~ I ~ , o~ o ~VIII) -HzO / l \ ¦ CH35CHzC~12C~ SC~12CI~CH~¦
\--l ICH2--CHZ 1 \~IW~222 lXXXVI) ~_ ~ ~ ¦ H!~c~cHzcHzc~ l II~CS~ ~
~ ~ , I
120 ¦ ._ L L~ ~scl , CU~cO;~oH ~ ~
--1~ 'H ~ ~ H' ~0 C~SCH~ j,\
-H20 ¦ H3CSH lLXXlV) I \ ~_.. __ ~ C~ ~ I ~SC~
/~IX~ lX) ~Xl) WO 93/130~9 PCI`/BR92/00020 6A 2~ 0373~
H 0~xxxv~xxxa~
H~CSCH2CH2C~C-C;~ -Co . ~2~ CH~ I .H~CSH
UW- 1~0 1.2~20 ~c I"~c.c-c~'"
~_ ~ H /
I l~WIII~ , I ~--~V.I60 H~,CSCH~,CH2CH-C,H CH~C~H C~ ~ I C~-~O~p~ 111 j~,w-~lz lc~ I;CH3 C ~ Hl ~o I~TP~. H5C ~!~ CH H
I W~1711 S~CH~
H~C~
hlW~2011 SCH~ ¦
xv1 ~2 I~Y UW. IC2 /-H~C~ H~C~CH2CH2~HC~2XH~¦
~W.I90 "~
~C5CH2CH2CH ,;~¦ H 0 ~ m~bl~ ~O-Z¦
IXXV~XX 1111 ~ I TPI~ HO H
~H~C CHC H 7 ~v~
¦ H2i Cl ~ 5CH
112~ ,C-CH2~C~ /
I~UV) ,1 ~ CII I
~ i Xll) 21~379b ~ ' t -H~ ' ', ~ "'' .
Y1~2Yl N~C# ~ ~¦ HS 5 H
1~1~0 ~o1/ 1~2~0 ' ~
H2C~CH-CH-CH C~ ¦ ~1 ~Sc~.a~2~H-cN~
~XXIv~X)~I~ ~I~LIJll ~SH~ ~ ' ~Vlll A
~H~CSH
H3CSH ~XII.XX) SCI~ ¦
1 2C CH HCHZCH~ ~1 .' ~ IU~
lXlX~xxxl x~
H C~c~l-c~ci-~H
iMW-220 SCH~
h~C5H l WO 93/13059 PCI`/BRg2/00020 6C ~ 7 ~ ~
t,=~,~, ~ ~ ' ' . .
WO93J130~9 PCT/BR92J00020 A.1.~ - O J ABSORPTION AN~ AUTO-OY.lDATIOM: formation of an addition compound between 02 and MTPA, which is regulated by dissolution of O~ in org~nic medium. From that point onwards., eith~r MTPA pero:cyacid is formed, which le~.~. to MTPA acid, or the reaction evolves. to form~tion of fr~e r~dicals., as mercaptide, which in turn leads, to formation of disulfides and heavy compounds.
WO 93/13059 PCr/BR92/00020 2~37~
., ~ W.... Vl ~n ~ ~ 3 ~ ~ o .
~ ws s ~ ^ , ~ s o o ~0 ~" c S S ~ S ~ \ ¦
~ Q, s \ \ S
o 3 _ ~ ~
/1 1 i\o ~ ,, ~
o,~
~o ~0 ,~
n S ". O ,~!
o ~ ~, ~ ~ O. n ~ æ s Q n ~ c~ o X ~
2103 7~u ., A.~.2 - ALDOL CONDENSATIONS IN AClD MEDlUM: reactlons catalyzed by ~clds, favored by the sta~illty of MTPA
enolic form. Dimers, trimers and poly~ers are formed:
_ WO 93/13059 PCr/BW2/00020 w ~3~
t o~ ~ ~
o .. .
,S ~=
> X ~ T
T_ ~--O
r ~ --n--~-- n O
~ /~
1 T~ O
¦ ~ x . ", o O i I ~
O ~ 'S ~
n _ O
. . ~
Il"
o 10 ~ ~I
o ~
X ",I
~ ~ O ,~ ~
O ~
2~ ~ 37 9 b A.1.3 - THERMAL DECOMPOSITION: reactions of MTPA and decomposition products thereof, significant at a ~ 65~C
temperature. The presence of metals accelerates this type of reaction. This thermal decomposition displaces the equilibrium of A.1.1 and A.1.~ and causes reaction~
of the A.1.4 type, due to release of methyl mercaptan in the organic medium.
WO 93/13059 PCI~/BR92~00020 21~3~
n ;r~ 5 D
~ I J
~ S
.. ,.t , S ~S o ~c .. ~
,, o --n--~ ~2 ~0 ~I Xn ~0~ ~= N n =
NS "~ ~ ln ~S ~ ¦
o' ;~
3: o :~-~S 1 ~
o r \n/ O --o ~ ~1 a-/ _ ~ 11 ~ .S~
S
. . .
2~ ~3~ 13 A.1.4 - AD~ITION3 AN~ SUBSTITUT1ON3: Methyl mercapt~n c~uses ~ormation of m~rcapt~l ~nd hemithioacet~l type addition compounds. Thioeter type compounds are formed through reactions with car~oxylic acids pres~nt. .. . --~
.. .. _ ...... ~.. ... . _ .. . . . . ...... .. ... ..
WO 93/13059 PCI~/BR92100020 21~37~
2 n Il s o ~- n ~ s s N I it~ r n ~0 . ~=
m ~ /1 \
~n u- s Q
. ~
n ~
s--n / 1 \ ¦ L~
% 1l ~ s n n s ~
c n n ~;C
s ~
w~ ~n n x c s ~ n n-s `~ ~ 3~ ' o l z . ~ ', . c . ~
-- u~ s ~> ~
S r,S
O ''I r s ~ S, ~_ ~ o ~ 11 S N S N
~> s ~
~J ~
~03~g6 15 A.l.5 - ~ECARBONYLATION5: the presence of mercapt~ns, p~rticularly At high temperatures, f~cilitate aldehyde decar~onyl~tions, as in the c~se of MTPA, ~nd form corres.p~nding org~nic sulfides.
.. . .
WO 93/13059 P~/BR92/00020 16 21~7~
S 5 ~ l o ,~s C ~ I n ~_n_n _ ~5 1 I In o 0 ~ n J
n ,~F I O ,.
-/o O I :1:
. ~ . ' ~ O ~,5 n S
. ~ 'n ~.
"~
a~
~z o~ ~_ X ,,}~
S
,,~ "
-;r s S~ ~o S ' ~ , S
-,,_5 W093/13059 PCT/BR92/~20 2~ ~379~ -The initial step for MTPA decomposition involves oxygen absorption, leading to auto-oxidation facilitated ~y the characteristics of great st~bility of MTPA enolic form.
This is followëd by aldol condensations in acid medium, catalyzed by the acidity resulting from the peroxyacid formed os the corsesponding car~oxylic acid itself.
Thermically controlled decompositions leading to the formation ~f methyl mercaptan, acrolein and ethylene occur from MTPA ~ust as it is and/or fsom MTPA
peroxyacid.
MTPA thermal decomposition studies in an inert atmosphere indicate that at temperatures below 90 C
mercapt~n formation through heating is small. However.
above lr~5Gc therm~l decomposition becomes a factor of great importance for the stability of this moIecule.
Experimental o~servations by the Applicant show that in an oxygen atmosphere the decomposition seleasing methyl mercaptan is made much easier and occurs even at low 2~ temper~ture, probably due to the p rticipation of peroxyacid in the process.
W093/1~9 PCT/BR92/00020 ~8 2~ ~37~
BEST MODE FOR CARRYlNG OUT THE INVENTION
The invention relates to a st~biliz~ng compo~t~on for S-sub~tituted ~ldehydes with the general formula (Il:
~ CH - CH - CHO
having 4-15 carbon atoms, where:
~1 = Cl-C5 alkyl, C6-C~ aryl, furfuryl and benzyl R~ = H, Rl R3 - H, Rl characterized by being based on a prototropic agent ~A) in aC.sociation with an 02 abstracting agent ~B). Suc~l A
and B compounds may be chosen from:
TABLE A~8 A.1: an aromatic or B.1: a subtituted heterocyclic aromatic phenol or hydroquinone, amine, such as pyridine, such as p-t-butylphenol dimethyllaniline. ~PTBF), BHT ~,6 di-quinoline, ~-hydroxy- terbutyl, 4-methyl quinoline, collidine, phenol) picoline, lutidine WO93/1~59 PCT/BR92/~020 .~
2i~
A.~.: alcanolamines or B.~: acid or unsaturat-non-aromatic cyclic ed antioxidant agents, amines, ~uch as tri- such as ascorbic acid~
etanolamine (TEA) (AA), beta-carotene N-methylmorpholine A.3 : lactams, such as N-methyl pyrrolidone The stabilizing composition is made up by and A and B, except for the following two pairs: A = pyridine~B = p-t-butyl phenol and A = quinoline/B = p-t-butyl phenol.
Preferably, the following fitabilizing compositions are indic~ted:
COMPOSITION ~ A B I
C2 PY~Y~INE AA
C3 ~UlNOLINE AA
More ~pecifically, composition A/B may be TEA/AA.
The role of the prototropic agent A is eliminating acid centers responsible for additional aldol condensations, and agent B competes for O~, thus avoiding the ~a~
t~igge~ing of undesirable reactions in ~-substituted aldehyde.
The stAbilizing composition for 5-substituted aldehyde with formula II) is characterized by the fact that it is ed in an amount of 500-1500 ppm, preferably 1004 ppm The mol~r ratio of A/B components is comprised between 5:95 and 5:50. The preferred stabilizing composition is further TEA~AA at 1000 ppm, with 10~-50% AA in TEA.
The synergy of the stabilizing composition as regard~.
the use of isolated amines was noted, as propo6ed in the state of the art ~see table 1 of examples), with the ~ta~ilized ~-substituted aldehyde appearing without the yellowiæh coloring typical of the existence of deaomposltion products. Upon submitting the stabilized aldehyde to chrom~tography analysis, few components are found to form by transformation of the existing aldehyde itelf, and therefor stabilization is quite efficient.
The stabilizing composition also does not interfere with su~sequent handlings of the stabilized aldehyde, since A
and B componentC. remain in the distillation re~idue ~see table 4 of examples).
It was also evidenced Isee table ~ of examples) that the stabilization is efficient at varying temperatrues, for example, MTPA tabilized with TEA/AA and kept at 50~C
W093/1~59 PCT/BR92/00020 ._ 21 ~37~6 for 15 days suffered a decrease of less than 2% during storage.
This invention also concerns a process for stabilizing S-substituted aldehydes wit~ the formula ~I) characterized by addition to said aldehyde of the A~B
sta~ilizing compositon as descri~ed above.
INFLUENCE OF WATER CONTENT
The presence o~ w~ter ln 3-su~stituted aldehyde or the compositon interferes with the sta~ilizing c~pacity of the A~B system added, mainly when the aldehyde h~s contact with metals or car~on steel, for under such conditions the amine type component A will release OH-ions which wiil set off aldol condensations.
In the case of TEA, for instance, the following will occur in the presence of water:
N (CHZCH20H)~ ~ HZO ~~~~ HN~ tCHZCH20H)~ ~ OH
Aldol conden~ation reaction~ set off in an alcaline medium tparticul~rly if there is car~on steel in such medlum) are, for MTPA:
WO93/13059 PCT/BR92/~020 21~379~
O l H3CSCH2CH2C t OH- --> H3CSCN2CNC
H a H
O O ~H20 ~C~ t ~Pl > ~C~C-C -> P~
< I ~ <~_ a 0 ~ H l60 C~ -~H
~Pll 190~ I
SC~
t N20 al~ol c~enc~tion co~ntc Thus, the pr~ence ~f water either in S-su~stituted ~ldhyde or in the sta~ilizing compofiition must ~e minimurn. The proce~-fi for ~,ta~ili2ing ~-su~stituted aldehydes with formula (I) is characterized ~y the fact the the aldehyde contains a m~ximum of ~Ob ppm of water, prefer~ly lesc .than ~bb ppm, for sta~ilizing temperatures up to 50 C.
In terms of application of S-ubstituted aldehyde in industrial proces~, addition is recommended at the time of its manufacture, after its initi~l distillation and transfer to containers, before water is formed as decomposition product.
CARBON STEEL
Experimental o~servation& showed that car~on steel exerts two distinct effects on 5-su~ctituted aldehydec.:
210'~7iJ~
1) at temperatures ~ 50 C: carbon steel stabilizes aldehyde in relation to the isolated action of oxygen, probably due to the steel fiurface c~pacity to abstract 02 from the medium. More particularly, for MTPA
complexation of its enol may occur, which is respon~ible for the auto-oxidation exercised by metal ions.
~) at temperatures J 50~-C: carbon steel contributes to aldehyde decomposition, specially in the presence of oxygen. ln the case of MTPA, the methyl mercaptide or enol formed prob~ly att~ck the steel ~urface and release Fe~, Fer~ ~nd Mn2~ metal ions, which in turn catalyze the aldehyde oxidating composition.
The stabilizing process proposed for S-subs.tituted aldehydes tI) is characterized by the aldehyde being or not being in contact with c~r~on steel.
The AJB stabilizing composition proposed decre~ses the decomposition of S-substituted aldehydes in the presence of carbon steel and at all temperatures tested ~see examples, table lA). The stabilizing process is used in aldehydes subjected to temperatures in the range of ~5-100 C .
S-substituted aldehydes with formula (I) are characterized by cont~ining an AJB stabilizing aomposition as previously described.
W093/13059 PCT/BRg2/~20 210379~
~4 E X A M P L E S
gTABIL~ZING SYSTEM
1) ~YNERGIC ACTlON OF 5TABILIZING ~YSTEM
MTPA samples, whether stabilized or not, were weighed, packed into glass ampoules or UParr pumps" ~Teflon ampoules with carbon steel outer lining), clo~ed and su~i0cted to heating in a stove for definite periods of time, in amospheric air and absence of light. 5amples were then analyGed by oximation and~or gas chromatography for checking the stabilizing effect of ~ubstance~- mentioned in table A/B as well the synergic effect of composition A~B.
For comparative purposes, each test was confronted with a non-stabilized MTPA specimen subiected to the same kinetic conditions of heat treatment. Each test and each specimen were carried out in duplicate.
Samples were prepared ~y weighing in a analytical or microan~lytic~l balance of the chemical agent~s) tested as stabilizer~s) in convenient contents, in the range of 1000 to 2500 ppm of stabilizer in MTPA. The tests were carried out at temperatures of 50~C, 80C,and 120~C, in addition to room temperature.
W093/1~59 PCT/BR92~00020 %~ ~3 ~
Method~ ~f Analy~16 Gas chromatography Analyses ~y gas chromatography determined the chromatographic aspect of sample and the MTPA content by normalization at 100%.
~o~-age by oximation MTPA content was obtained through functional analy&is by potentiometric method.
~esult~
Table 1 below synthe~ize~ the te~t condition~ ~time, temperature~ amount of ~tabilizer) for each .ample and relevant sta~ilizer, as well a~:
- MTPA initial content - MTPA content after the heating stage for a definite period of time - s~mple coloring - MTPA decomposition and stabilization rate - GC chromatogram aspect stres~ing impurities formed.
The relative formation rate of impurity of molecular weight l~0 ~MTPA crotomer) was cho~en as indicative of MTPA decomposition.
- stabilization factor, defined ~s the quotient between t~e variation value of non-stabilized MTPA content and ~tabilized MTPA content.
WO 93/13059 PCI/BRg2/00020 ~ Q3~9~
TAB LE
STA81LIZATION : : PPII OF : TEST
IIASS IN ~LAT10 N : STA8.: EAtH :T~P.: TlHE
No.: IrrPA : STABILIZER :TO llTPA : PPH: SI~BIL. :lC) :HOURS
1.1 :Distillate 26/10: - : - : - : - : 120: 15 1.2 :Dictillate 26/10: Pyridine : 1.2 ul Pyridine/el IrlPA: 1000 : 1000 : 120: 15 1.3 :Distlllate 26/10: 9uinoline :1.2 ul ~uinoline/~ PA: 1000 : 1000 : 120: 15 2.1 :Distillate 26110: - : - : - : - : 80: 90 2.2 :Distillate 26/10: Pyridine : 1.2 ul Pytidine/-l IIPTA: 2000 : 2000 : ôO: 90 2.3 :Distillate 26110 :Di-ethylanil3ne: 2.2 ul Pyriaine/-l liPTA: 2000: 2000 : 60: 90 1 5 : : : : : ~800pp-2.4 :Distillate 26/10 :Pyridine-Asco~: 2 ul Pyridine/-l IITPA : 2200 :Pyridine : 80: 90 bic Acid : O.~q Ascorbic Acid : : ~00 pp-:
: Aw.Acid:
: 1800 pp-:
2.8 :Distillate 26/10 :Pyridine-Awor-: 2 ul Pyridinel-il IITPA: 2200: Pyridine: 50: 90 :bic Acid : O.~q Aworbic Acid : : ~00 ppu:
: Asc.Acid:
3.1 :Distillate 27110: - : ~ 80: 115 3.2 :Distillate 27/10 :Dy ethylaniline:2.2Dy ethylaniline/~ lPA: 2000: 2000 : 80: 115 : : : : : lôOOpp:
~a~ 27 3.3 :Distillate 27/10 :Pyritine-Ascor-: 2ul Pyridine/al IrrPA : 2200: Pyridine: 80: 115 :bic Acid : 0.~9 Ascorbic hid : : ~00 ppa:
: Asc.Acid: :
~.1 :Dlstlll~te 27/10: - : - : - : - :B0: 84 : : 1530pp~ :
o r \n/ O --o ~ ~1 a-/ _ ~ 11 ~ .S~
S
. . .
2~ ~3~ 13 A.1.4 - AD~ITION3 AN~ SUBSTITUT1ON3: Methyl mercapt~n c~uses ~ormation of m~rcapt~l ~nd hemithioacet~l type addition compounds. Thioeter type compounds are formed through reactions with car~oxylic acids pres~nt. .. . --~
.. .. _ ...... ~.. ... . _ .. . . . . ...... .. ... ..
WO 93/13059 PCI~/BR92100020 21~37~
2 n Il s o ~- n ~ s s N I it~ r n ~0 . ~=
m ~ /1 \
~n u- s Q
. ~
n ~
s--n / 1 \ ¦ L~
% 1l ~ s n n s ~
c n n ~;C
s ~
w~ ~n n x c s ~ n n-s `~ ~ 3~ ' o l z . ~ ', . c . ~
-- u~ s ~> ~
S r,S
O ''I r s ~ S, ~_ ~ o ~ 11 S N S N
~> s ~
~J ~
~03~g6 15 A.l.5 - ~ECARBONYLATION5: the presence of mercapt~ns, p~rticularly At high temperatures, f~cilitate aldehyde decar~onyl~tions, as in the c~se of MTPA, ~nd form corres.p~nding org~nic sulfides.
.. . .
WO 93/13059 P~/BR92/00020 16 21~7~
S 5 ~ l o ,~s C ~ I n ~_n_n _ ~5 1 I In o 0 ~ n J
n ,~F I O ,.
-/o O I :1:
. ~ . ' ~ O ~,5 n S
. ~ 'n ~.
"~
a~
~z o~ ~_ X ,,}~
S
,,~ "
-;r s S~ ~o S ' ~ , S
-,,_5 W093/13059 PCT/BR92/~20 2~ ~379~ -The initial step for MTPA decomposition involves oxygen absorption, leading to auto-oxidation facilitated ~y the characteristics of great st~bility of MTPA enolic form.
This is followëd by aldol condensations in acid medium, catalyzed by the acidity resulting from the peroxyacid formed os the corsesponding car~oxylic acid itself.
Thermically controlled decompositions leading to the formation ~f methyl mercaptan, acrolein and ethylene occur from MTPA ~ust as it is and/or fsom MTPA
peroxyacid.
MTPA thermal decomposition studies in an inert atmosphere indicate that at temperatures below 90 C
mercapt~n formation through heating is small. However.
above lr~5Gc therm~l decomposition becomes a factor of great importance for the stability of this moIecule.
Experimental o~servations by the Applicant show that in an oxygen atmosphere the decomposition seleasing methyl mercaptan is made much easier and occurs even at low 2~ temper~ture, probably due to the p rticipation of peroxyacid in the process.
W093/1~9 PCT/BR92/00020 ~8 2~ ~37~
BEST MODE FOR CARRYlNG OUT THE INVENTION
The invention relates to a st~biliz~ng compo~t~on for S-sub~tituted ~ldehydes with the general formula (Il:
~ CH - CH - CHO
having 4-15 carbon atoms, where:
~1 = Cl-C5 alkyl, C6-C~ aryl, furfuryl and benzyl R~ = H, Rl R3 - H, Rl characterized by being based on a prototropic agent ~A) in aC.sociation with an 02 abstracting agent ~B). Suc~l A
and B compounds may be chosen from:
TABLE A~8 A.1: an aromatic or B.1: a subtituted heterocyclic aromatic phenol or hydroquinone, amine, such as pyridine, such as p-t-butylphenol dimethyllaniline. ~PTBF), BHT ~,6 di-quinoline, ~-hydroxy- terbutyl, 4-methyl quinoline, collidine, phenol) picoline, lutidine WO93/1~59 PCT/BR92/~020 .~
2i~
A.~.: alcanolamines or B.~: acid or unsaturat-non-aromatic cyclic ed antioxidant agents, amines, ~uch as tri- such as ascorbic acid~
etanolamine (TEA) (AA), beta-carotene N-methylmorpholine A.3 : lactams, such as N-methyl pyrrolidone The stabilizing composition is made up by and A and B, except for the following two pairs: A = pyridine~B = p-t-butyl phenol and A = quinoline/B = p-t-butyl phenol.
Preferably, the following fitabilizing compositions are indic~ted:
COMPOSITION ~ A B I
C2 PY~Y~INE AA
C3 ~UlNOLINE AA
More ~pecifically, composition A/B may be TEA/AA.
The role of the prototropic agent A is eliminating acid centers responsible for additional aldol condensations, and agent B competes for O~, thus avoiding the ~a~
t~igge~ing of undesirable reactions in ~-substituted aldehyde.
The stAbilizing composition for 5-substituted aldehyde with formula II) is characterized by the fact that it is ed in an amount of 500-1500 ppm, preferably 1004 ppm The mol~r ratio of A/B components is comprised between 5:95 and 5:50. The preferred stabilizing composition is further TEA~AA at 1000 ppm, with 10~-50% AA in TEA.
The synergy of the stabilizing composition as regard~.
the use of isolated amines was noted, as propo6ed in the state of the art ~see table 1 of examples), with the ~ta~ilized ~-substituted aldehyde appearing without the yellowiæh coloring typical of the existence of deaomposltion products. Upon submitting the stabilized aldehyde to chrom~tography analysis, few components are found to form by transformation of the existing aldehyde itelf, and therefor stabilization is quite efficient.
The stabilizing composition also does not interfere with su~sequent handlings of the stabilized aldehyde, since A
and B componentC. remain in the distillation re~idue ~see table 4 of examples).
It was also evidenced Isee table ~ of examples) that the stabilization is efficient at varying temperatrues, for example, MTPA tabilized with TEA/AA and kept at 50~C
W093/1~59 PCT/BR92/00020 ._ 21 ~37~6 for 15 days suffered a decrease of less than 2% during storage.
This invention also concerns a process for stabilizing S-substituted aldehydes wit~ the formula ~I) characterized by addition to said aldehyde of the A~B
sta~ilizing compositon as descri~ed above.
INFLUENCE OF WATER CONTENT
The presence o~ w~ter ln 3-su~stituted aldehyde or the compositon interferes with the sta~ilizing c~pacity of the A~B system added, mainly when the aldehyde h~s contact with metals or car~on steel, for under such conditions the amine type component A will release OH-ions which wiil set off aldol condensations.
In the case of TEA, for instance, the following will occur in the presence of water:
N (CHZCH20H)~ ~ HZO ~~~~ HN~ tCHZCH20H)~ ~ OH
Aldol conden~ation reaction~ set off in an alcaline medium tparticul~rly if there is car~on steel in such medlum) are, for MTPA:
WO93/13059 PCT/BR92/~020 21~379~
O l H3CSCH2CH2C t OH- --> H3CSCN2CNC
H a H
O O ~H20 ~C~ t ~Pl > ~C~C-C -> P~
< I ~ <~_ a 0 ~ H l60 C~ -~H
~Pll 190~ I
SC~
t N20 al~ol c~enc~tion co~ntc Thus, the pr~ence ~f water either in S-su~stituted ~ldhyde or in the sta~ilizing compofiition must ~e minimurn. The proce~-fi for ~,ta~ili2ing ~-su~stituted aldehydes with formula (I) is characterized ~y the fact the the aldehyde contains a m~ximum of ~Ob ppm of water, prefer~ly lesc .than ~bb ppm, for sta~ilizing temperatures up to 50 C.
In terms of application of S-ubstituted aldehyde in industrial proces~, addition is recommended at the time of its manufacture, after its initi~l distillation and transfer to containers, before water is formed as decomposition product.
CARBON STEEL
Experimental o~servation& showed that car~on steel exerts two distinct effects on 5-su~ctituted aldehydec.:
210'~7iJ~
1) at temperatures ~ 50 C: carbon steel stabilizes aldehyde in relation to the isolated action of oxygen, probably due to the steel fiurface c~pacity to abstract 02 from the medium. More particularly, for MTPA
complexation of its enol may occur, which is respon~ible for the auto-oxidation exercised by metal ions.
~) at temperatures J 50~-C: carbon steel contributes to aldehyde decomposition, specially in the presence of oxygen. ln the case of MTPA, the methyl mercaptide or enol formed prob~ly att~ck the steel ~urface and release Fe~, Fer~ ~nd Mn2~ metal ions, which in turn catalyze the aldehyde oxidating composition.
The stabilizing process proposed for S-subs.tituted aldehydes tI) is characterized by the aldehyde being or not being in contact with c~r~on steel.
The AJB stabilizing composition proposed decre~ses the decomposition of S-substituted aldehydes in the presence of carbon steel and at all temperatures tested ~see examples, table lA). The stabilizing process is used in aldehydes subjected to temperatures in the range of ~5-100 C .
S-substituted aldehydes with formula (I) are characterized by cont~ining an AJB stabilizing aomposition as previously described.
W093/13059 PCT/BRg2/~20 210379~
~4 E X A M P L E S
gTABIL~ZING SYSTEM
1) ~YNERGIC ACTlON OF 5TABILIZING ~YSTEM
MTPA samples, whether stabilized or not, were weighed, packed into glass ampoules or UParr pumps" ~Teflon ampoules with carbon steel outer lining), clo~ed and su~i0cted to heating in a stove for definite periods of time, in amospheric air and absence of light. 5amples were then analyGed by oximation and~or gas chromatography for checking the stabilizing effect of ~ubstance~- mentioned in table A/B as well the synergic effect of composition A~B.
For comparative purposes, each test was confronted with a non-stabilized MTPA specimen subiected to the same kinetic conditions of heat treatment. Each test and each specimen were carried out in duplicate.
Samples were prepared ~y weighing in a analytical or microan~lytic~l balance of the chemical agent~s) tested as stabilizer~s) in convenient contents, in the range of 1000 to 2500 ppm of stabilizer in MTPA. The tests were carried out at temperatures of 50~C, 80C,and 120~C, in addition to room temperature.
W093/1~59 PCT/BR92~00020 %~ ~3 ~
Method~ ~f Analy~16 Gas chromatography Analyses ~y gas chromatography determined the chromatographic aspect of sample and the MTPA content by normalization at 100%.
~o~-age by oximation MTPA content was obtained through functional analy&is by potentiometric method.
~esult~
Table 1 below synthe~ize~ the te~t condition~ ~time, temperature~ amount of ~tabilizer) for each .ample and relevant sta~ilizer, as well a~:
- MTPA initial content - MTPA content after the heating stage for a definite period of time - s~mple coloring - MTPA decomposition and stabilization rate - GC chromatogram aspect stres~ing impurities formed.
The relative formation rate of impurity of molecular weight l~0 ~MTPA crotomer) was cho~en as indicative of MTPA decomposition.
- stabilization factor, defined ~s the quotient between t~e variation value of non-stabilized MTPA content and ~tabilized MTPA content.
WO 93/13059 PCI/BRg2/00020 ~ Q3~9~
TAB LE
STA81LIZATION : : PPII OF : TEST
IIASS IN ~LAT10 N : STA8.: EAtH :T~P.: TlHE
No.: IrrPA : STABILIZER :TO llTPA : PPH: SI~BIL. :lC) :HOURS
1.1 :Distillate 26/10: - : - : - : - : 120: 15 1.2 :Dictillate 26/10: Pyridine : 1.2 ul Pyridine/el IrlPA: 1000 : 1000 : 120: 15 1.3 :Distlllate 26/10: 9uinoline :1.2 ul ~uinoline/~ PA: 1000 : 1000 : 120: 15 2.1 :Distillate 26110: - : - : - : - : 80: 90 2.2 :Distillate 26/10: Pyridine : 1.2 ul Pytidine/-l IIPTA: 2000 : 2000 : ôO: 90 2.3 :Distillate 26110 :Di-ethylanil3ne: 2.2 ul Pyriaine/-l liPTA: 2000: 2000 : 60: 90 1 5 : : : : : ~800pp-2.4 :Distillate 26/10 :Pyridine-Asco~: 2 ul Pyridine/-l IITPA : 2200 :Pyridine : 80: 90 bic Acid : O.~q Ascorbic Acid : : ~00 pp-:
: Aw.Acid:
: 1800 pp-:
2.8 :Distillate 26/10 :Pyridine-Awor-: 2 ul Pyridinel-il IITPA: 2200: Pyridine: 50: 90 :bic Acid : O.~q Aworbic Acid : : ~00 ppu:
: Asc.Acid:
3.1 :Distillate 27110: - : ~ 80: 115 3.2 :Distillate 27/10 :Dy ethylaniline:2.2Dy ethylaniline/~ lPA: 2000: 2000 : 80: 115 : : : : : lôOOpp:
~a~ 27 3.3 :Distillate 27/10 :Pyritine-Ascor-: 2ul Pyridine/al IrrPA : 2200: Pyridine: 80: 115 :bic Acid : 0.~9 Ascorbic hid : : ~00 ppa:
: Asc.Acid: :
~.1 :Dlstlll~te 27/10: - : - : - : - :B0: 84 : : 1530pp~ :
4.2: Distillate 27/lO:Pyridine-Ascor-:1.7ul Pyridinel-l HTPA : 2200: Pyridine: 80: 8 :bic Acid :0.7i~g A corbic Acid : : 710 ppe : Aw.hid:
: 1100 pp~: :
~.3 : Dictillate 27/lO:Pyridine-As- :1.2 ul Pyritine/ol I~PA: 2200 : Pyridine: 80: ô4 :corbic Acid :I.lbg Ascorbic Adid :: IlOOppe : lsc.Ac~a:
: IBOOpp~l:
6.1 : Distillate 27110: : : : : :
: Redistillate : - : - : - : : 80: 110 : 1~./ 121B3 : 1600pp~:
6.3 : Distillate :Pyridine-As- :2.2ul Pyridine /-1 I~Pl: 2200 : Pyridine: B0 : 110 : Redistillate :corbic Acid : 0.~0 og Ascorbic Acid: : 600pp : 14/12183 : : : : lsc.lcid:
: I900pp~
6.6 : Distillate :Quinoline As- :2.1ul Quinoline/~l IITPA: 2500 : Pyridine: 80 : 110 : Redistillate :corbic Acid : 0.~ ~9 Ascorbic Acid : : ~OOpp : 1~/12/83 : : : : Asc.Acid:
W O 93/13059 PC~r/B1~92/00020 ~1~37...~
~.~
7.1 : D3stil1ate 27/10 : : : : : :
: Redistillate : - : - : - : - : 80 : 115 : 19/12183 7.2 : Di~tillate ' : Redistillate :TriethanoJa- : 0.988 111 HTPA : 1000 : 1000 : 60 : 115 : 19/12183 :e}ne 900 W~: :
7.3 : Distillate :triethanola- :~0.90~ I TEA/ al HT,PA : 1000 : T U : 80 : 115 : :-ine 1 O : Redistillate :A~corb3c Acid : 0.096 9 A corbic Acid : : lOOp p : 19/1218~ : : : : Asc.lcld 7.5 : Di~tillate : 8-Hydroxy-: Redistillate : quinoline :1.0 q 8-Hydroxyquinoli- : 1000 : 1000 : ôO : 115 : 19/12/8~ : :ne 1 5 : : : : : 800 pp~ : :
7.6 : Distillate : 8-Hydroxy- :0.88~9 8-Hydroxyquinol} : 1000 : H.9. : 80 : 115 : Redistillate : qu}noline :ne 0.12~9 Ascorbic Acid : : lOOppo : 19112/83 : Ascorbic Acid: : : Asc.Aclt : :
7.11 : Di~tillate : N-~ethyl 2 0 : Red}stillate : Pyrrolidone : I ull-l HnPA : 1000 : 1000 : 80 : 115 : 19112183 7.16 : Ditillate : N-PkthyJ :1.2ul N-~ethyl ~orpho-: Redistillate : Horpholine : line / ~I Y1PA : 1000 : 1000 : 80 : 115 : 19/12/83 2 5 : : : : : 800pp~ : :
W O 93/13059 PC~rlB R92/00020 7 1~ Distillate Pyridine I ul solution 1000 Pyridine 80 115 Redistillate :Pira-tert-butyl 1 8-1 Pyridine at 200ppa 19/12/ô3 Phenol 0 38 9 PT2P PllaP
1600 pp~
7 15 Distillate Pyridine 2 ul solution 2000 Pyridine ôO 115 Redictillate Para-tert-butyl I ô nl Pyridine ~00 ppa 19/12/B3 Phenol 0 3B g PT8P PlBP
~TPA CONTENT CO~PONENT
1 0 CHRONA70GFU~ NTPA CONTENT VARIATION IN 190 CONTENT STA81LIZATL
SA~PLE ASPECT ASPECT A m R ICG~ PER RELATION TO 1~ RELATION ON FACTOR
No AFlER 7EST lESTNOR~ AT IOOS SPECI~EN TO SPECI~EN
1 1 Yellov vith dar~ hany co ponent~ ~1 3 - 11 6~/~1 29-0 282 1 00 precipitate 1 5 1 2 Yello~ hany co ponents 6~ 9 23 7 6 6516S 9/0 103 1 61 lless than - specieen 1 3 Yellov Nany co ponents 59 S lB l 8 36/59 ~-0 1~1 1 U
lless than 2 0 specie en~
2 1 Dar~ yellov hany co ponents 60 9 - 3 71/60 91-0 0611 1 00 2 2 Light yellov ~any co ponents 65 7 ~ 7~ 3 74165 6-0 0569 l lS
2 3 Light Yellov ~bny co ponents 68 ~ 7 51 1 7~/68 ~2-0 0255 1 2S
lless than 2 5 speciaen) 2~ 6 31~
2.~ :Very ligh yellw: Fe~ co ponents: 18.91 : 18.0 :1.57178.91-0.0199: 1.85 2.8 : Colorless :Fe~ co ponents: 82.8~ : 18.~ :0.646/82.8~-0.0078: 2.07 3.1 : Yello~ :Jbny co ponents: 56.7 : - :~.78/56.8-0.08U: 1.00 3.2 : Yellov :lbny co ponents: 70.5 : 13.1 :2.18/70.5-0.031 : 1.~6 3.3 : Light yelw to :Fe~l co-ponents: 77.7 : 20.9 : 1.99177.7-0.026: 1.9 : colorle~6 : : : : :
.1 : Dar} yellw :llany coeponents: 61.~ : - :7.65161.~-0.12~ : 1.00 .2 : Light yellw :Fe~ cwponents: 76.9 : 15.~ :2.2~/76.9~0.0291: 2.10 .3 : Light yellw to :Fe~r co ponents:78.6 : 17.2 : 3.11178.66-0.039: 2.27 1 0 : colorles6 6.1 : Yello~J :Ibny co ponents: 72.78 : - :12.66172.7-0.173: 1.00 6.3 : Colorless :Fe~ coyonents: 90.2 : 17.~ :2.99190.2-0.0253: 2.78 6.6 : 51ightly :Fe~l co~onentfi: 88.9 : 16.1 : 3.78/86.9-O.OU: 2.69 : yellw;sh 7.1 : Yellw :llany coeponents: 70.7 : nil : 1.3~M0.7-0.0618: 1.00 7.2 : Colorless :Fe~ co ponents: 89.8 : 19.2 :2.58/89.8-0.029 : 2.88 7.3 : Colorles~ :Fe~ co ponents: 91.9 : 21.2 :2.08/91.8-0.0266 : 3.60 7.5 : Light yellw :Fe~ cwponets: B7.8 : 17.1 :2.20/87.~0.0262 : 2.23 20 7.6 : llery light :Fe~l conponent6: 90.1 : 20.3 : 1.30/90.1-0.014 : 3.14 :yellw 7.11: Dar} yellw :Ibny conponents: 77.2 : 6.5 :3.38/77.2-0.0438 : 1.28 7.16: Yellw :llany co~onents: 78.3 : 7.6 : 2.~5178.3-0.0313: 1.30 7.14: Colorlefis :Fe~ cooponents: 90.2 : 19.5 : 2.03/90.2-0.022~: 2.99 : Colorless :Fe~l cooponents: gO.6 : 19.9 : 1.95190.6-0.0215: 3.11 W093/13059 PCT/BR92/~20 2~0379~ ` -~efore everything, addition of ascorbic acid ~lone, despite being capable of absorbing oxygen powerfully, is not indicated for stabilizing aldehydes, since as it is and acid it would catalyze aldol condensation reactions.
The synergic effect of A/B composition in MTPA
st~bilization as compared with application of substances individually is very clear, particularly amines such as pyridine, quinoline and dimethylaniline, as was done in the state of the art. Besides, amounts in the A/B
fitabiiizing sytem are lower than those recommended in the state of the art.
~tabilizer mass ratlos of 1000, 2000 and 2500 ppm and molar ratios of 10~, 20# and 50# of ascorbic acid in TEA
were tested for the stabilizing mixture. Triethanolamine is known to exhibit low toxidity, virtually no contribution to smell and a high boiling point ~206C at mm Hg), higher than MTPA, which positively recommends it for industrial h~ndling.
2) TEST WITH TEA/AA
Other more precise tests were carried out with the TEA/AA sta~ilizing system.
Samples wer~ prepared with mass and molar ratios as indicated below:
W093~13059 PCT/BR92/~020 ~ 937~
9.6 mg ascorbic acid (0.055 m mol) and 90.4 mg triethanolamine ~0.603 m mol) to 100 ml MTPA - actual molar ratio used: 8.4~ mol~r ascorbic acid to 91.6X
molar trieth~nolamine.
Tests were carried out at 50, 80 and lOO~C for heating periods of up to 360 hours t15 days).
Data obtained are shown in table 2, where each value is an average of two tegt repetitions with good relative accuracy. MTPA content wa~
determined by GC and oximation. By way of information, there are also included dat~ obtained at 50C for MTPA
oontact with carbon ste~l in the presence ~nd absence of a st~bilizing system.
BA~ n~T-~A-STABILI~
CO~IT10~ Tl~
67Hours SAtlPLES : : Reurks :: Results : . : Altehyte : GC
: : Aspect : ~Sl : ~S) :Stabilization : : Color : ~aueragel :~average) : Factor 2 5 HTPA : 50 : Colorless : 95.13 : 92.55 : I.OO
W O 93/13059 PC~r/B R92/0(H)20 2~37~
~IPA + Trlethanolaelne 50 Colorle~s 97 15 9~ 26 2 27 A~corblc Acid ~IPA 80 Light 79 2780 Il 1 00 yello~
S ~IPl t Trieth nola-ine 80 Colorle~s93 87 9~ 36 ~ 5 t A~cor~ic Acid ~TPA lO0 Dar~ 58 9169 83 1 00 yello~
~IPA ~ Ttiethanolad ne 100 Light 7~ 11 82 9~ 1 6 1 0 t A corbic Acid Yello~
~TPA ~ Ca~bon Steel 50 Colorle~t95 55 92 9~ 1 00 ~TPA t Car~on 5teel ~ 50 Colorles6 97 58 9~ 67 5 83 Trlethanolaeina ~worbic Acid BASE TEST - ~1PA - ST19ILIZERS
CONDITIONS TI~E
2 0 14~ Hwrs SA~PLES Re arks Re6ults Aldehyde GC
Aspect ISI l~ Stablll2Ation Color laverage~ laverage1 Factor 2 5 ~TPA 50 Colorless 89 7090 07 l 00 WO 93/13059 PCI'/BR92/00020 2~ ~7~
IITPA t Triothanolaeino 50 Colorle6s 97 59 93 ~8 B 30 t Ascorblc Aclt IllPl 80 Yello~ 68 39 ~3 16 100 IITP1 t TrlothanolaDine ôO Colorloss 86 ô7 88 80 2 66 t Ascotbic Acid lI`rP1 100 Yelloldsh ~l U 55 00 100 bro~m 16ticl~g~
I~PA t Triethanola~ine 100 Light 61 1576 38 15 t Ascorbic Acid yello~
IrlPA t Carbon 9teel 50 Colotless 92 3293 05 100 ISIPA t Carhon Steel t 50 Colorle6t 96 ~09~ 0ô 3 55 Trlethanola-ina t A~corbic Acid BISE TEST IITPl- STABILIZERS
CONDITIONS TIB
2~0 Hours SAIIPLES RQearks Results Aldehyde GC
Aspect ~S) ~51 Stabilization Colorla~eragel laveragel Factor lSlPA 50 Colorless 86 0283 58 100 IllPA t Trietbanola~ine 50 Colorless 96 89 9~ 07 11 09 t Ascorbic 1cid WO 93/~3059 PCI/BR92/00020 2i~379~
IlTPll : 80: Yello~ : 55.30 :63.13: 1.00 ItrPA t Trlethanolaelne: 80:Very : 79.55 : 83.5~: 2.31 t A~corbic Acld : : light : ~ello~ : ::
lilPl: 100: Yello~h: 30.22 :36.92: 1.00 : bro~m :
(sticky~ : : :
~IT.Pl t TriethanolaeiRc: 100:Ligh~ :52.5~ : 71.58: 1.~9 t A~corbic hid : : Yello~ : ::
111~1 t Carbon Steel : 50: Very : 91.52 : 92.21: 1.00 light yellw IIT.PA t Carbon Steel t: 50: Colorless: 95.95 : 93.00: 3.16Tricthanola~ine ~ :: : ::
Ascorbic Acid aAsE rEsr - llPA- STAalLlZERS
CONDITIONS TlIIE
360 Hours SAIIPLES : : Reurks: :Results : Aldehyde : GC
: A~pect : (S1 : (S~ :Stabillzation : Color : laverage~ :laverage~: ~actor llrPA : 50 : Colorless: 80.29 : 78.27: 1.00 WO 93/13059 PCI/BRg2/00020 3 7 9 ~
I~IPA ~ Trlcth~nol~ne 50 Colorloss 97 25 92 98: l7 71 t kcorblc Acld l~rPA : 80 Deep ~ 11 59 261.00 : Yello~l :
l~l~A t Triethanolaaine 80 l~ery 72 51 79 90 211 t Ascorbic lcid ligbt yello~
lllPA 100 Yello~dch 2~ ~6 29 23 1 00 bro~m I~t~clly~
IIIPA t Trlethanola lne: 100 Yellal ~ 02 56 39 1.36 t Ascotb1c Acid IrlPA t Carbon Steel 50 llery 89 56 88 ~0 1.00 light yello~
IrlPA t C rbon Steel t 50 Colorlecs 93 66 9163 195 Triethanola-ine t A6corbic Acid From Table ~, the efficient ~ehavior of this st~biIizing composition can be noticed. Thus, for MTPA with an 98.01~ initial content, it is noted that the content (dosed by oximation) is kept virtually unchanged at 97X
25 after a 15-day heating, while in the abs~nce of W093~13059 PCTtBR92/00020 2~ ~379~
sta~ilizer such content drops to 78X under the same thermal conditions.
The composition herein is effective for tabili2ing MTPA
at 50~C kept in contact with carbon steel.
PHY5 I CAL CHEM l CAL DATA ON ~3TAB I L I ZAT I ON:
Graph 1 s~ow~ the correlation of data in table ~, where in:
3TABILIZEI:) MTPA AT 50C
I I NON--STABILIZED MTPA AT 50C'C
V STABILIZED MTF'A AT 100C C
WO 93/13059 PCr/BR92/00020 38 2~7~
'~
1~ _ o . . . , . :._ 100 2 )0 O Tlme IH) WO93/1~59 PCT/BR92/~020 .
2~
It is noticed thht there is ~ first order kinetic variation between MTPA contents and time values for 50 and 30~C temperature~. At 100C the correlation is not linear, which ~ùggests ~n interference of mechanisms, particularly decomposition by heat, operating at this temperature and with little operation up to 80C.
The calculation of initial speed constants at the three - temperatures for non-~t~bilized and ~tabilized MTPA
leads to data in Table 3.
1'0 XINETIC DATA RELATIVE TO NON-STABILIZED AND ~TABIL~ZED
MTPA - ~PEED CON~TANT~ ~X) AT EACH TEMPERATURE
Teeperature ~ .tabilized : Stabilized I CI : '~A : IITPA*
: k ~hour~l, : kld~ (hour~l l K(d~
: 5.~xlO-~ ) : 1.3xlO t~ : 1.2xlO-' ): 2.9xlO'~) : 2.2x10-3 ) : 5.3xlO ~) : 3.7xlO'~): 8.~xlO-~) l~s~ : 5.3xlO 3 ) : 1.26xlO~1) : 1.2xlO 3 ): 3.0xlO ~) $ Stabilizer: 10~ molar Ascorbid Acid - Triethanol-amine at 1000 ppm.
W093/l3~9 PCT~BR92/~20 2 1 ~ 3 7 3 ~
4~J
l*~ The X value is that of the pseudo-first order in}tial speed con&tant calculated between times zero and 67 hours in Table 2.
As from table 3, the calculation of activation energies for the two situations leads to the following values:
Activ~tion energy - HTPA decomposition..10.5 Kcal~mol non-cta~ilized Activation energy - MTPA` decomposition..25~5 Xcal/mol stabilized Thus, kinetic~lly and thermodynamically, MTPA
stabilization with the TEA/AA st~ilizing composition is equiv~lent to an increase of two ~nd h~lf times in the magnitude of activation energy, which quantifies the degree to which this composition is Llocked ~y the presence of staLilizer.
An extrapolation of data in tables 2 and 3 according to correlation log X = f (1/T) for 30C ena~les calculation of speed constant at this temperature in K = 1.15 x 10-5 hour for sta~ilized aldehyde. This value mean~ a rate forecast for MTPA dropping le~s than lX for 1-month storage under environmental conditions in the presence of ~ta~ilizer.
ALDEHY~E ~ISTILLATION
W093/13059 PCT/B W2/0~20 2~
This test shows the mass distribution of TEA/AA
stabilizing components in MTPA distillation in its light, distillate and residue fractions. ~tabilizer monitoring wa~ conducted by following up TEA, since the AA high boiling point authorizes the assumption that this component remains in the distillation residue.
The test was carried out by discontinuous distillaton in a 5 cm outer diameter, 65 cm high glass column fitted with 7 Teflon pierced plates.
: 1100 pp~: :
~.3 : Dictillate 27/lO:Pyridine-As- :1.2 ul Pyritine/ol I~PA: 2200 : Pyridine: 80: ô4 :corbic Acid :I.lbg Ascorbic Adid :: IlOOppe : lsc.Ac~a:
: IBOOpp~l:
6.1 : Distillate 27110: : : : : :
: Redistillate : - : - : - : : 80: 110 : 1~./ 121B3 : 1600pp~:
6.3 : Distillate :Pyridine-As- :2.2ul Pyridine /-1 I~Pl: 2200 : Pyridine: B0 : 110 : Redistillate :corbic Acid : 0.~0 og Ascorbic Acid: : 600pp : 14/12183 : : : : lsc.lcid:
: I900pp~
6.6 : Distillate :Quinoline As- :2.1ul Quinoline/~l IITPA: 2500 : Pyridine: 80 : 110 : Redistillate :corbic Acid : 0.~ ~9 Ascorbic Acid : : ~OOpp : 1~/12/83 : : : : Asc.Acid:
W O 93/13059 PC~r/B1~92/00020 ~1~37...~
~.~
7.1 : D3stil1ate 27/10 : : : : : :
: Redistillate : - : - : - : - : 80 : 115 : 19/12183 7.2 : Di~tillate ' : Redistillate :TriethanoJa- : 0.988 111 HTPA : 1000 : 1000 : 60 : 115 : 19/12183 :e}ne 900 W~: :
7.3 : Distillate :triethanola- :~0.90~ I TEA/ al HT,PA : 1000 : T U : 80 : 115 : :-ine 1 O : Redistillate :A~corb3c Acid : 0.096 9 A corbic Acid : : lOOp p : 19/1218~ : : : : Asc.lcld 7.5 : Di~tillate : 8-Hydroxy-: Redistillate : quinoline :1.0 q 8-Hydroxyquinoli- : 1000 : 1000 : ôO : 115 : 19/12/8~ : :ne 1 5 : : : : : 800 pp~ : :
7.6 : Distillate : 8-Hydroxy- :0.88~9 8-Hydroxyquinol} : 1000 : H.9. : 80 : 115 : Redistillate : qu}noline :ne 0.12~9 Ascorbic Acid : : lOOppo : 19112/83 : Ascorbic Acid: : : Asc.Aclt : :
7.11 : Di~tillate : N-~ethyl 2 0 : Red}stillate : Pyrrolidone : I ull-l HnPA : 1000 : 1000 : 80 : 115 : 19112183 7.16 : Ditillate : N-PkthyJ :1.2ul N-~ethyl ~orpho-: Redistillate : Horpholine : line / ~I Y1PA : 1000 : 1000 : 80 : 115 : 19/12/83 2 5 : : : : : 800pp~ : :
W O 93/13059 PC~rlB R92/00020 7 1~ Distillate Pyridine I ul solution 1000 Pyridine 80 115 Redistillate :Pira-tert-butyl 1 8-1 Pyridine at 200ppa 19/12/ô3 Phenol 0 38 9 PT2P PllaP
1600 pp~
7 15 Distillate Pyridine 2 ul solution 2000 Pyridine ôO 115 Redictillate Para-tert-butyl I ô nl Pyridine ~00 ppa 19/12/B3 Phenol 0 3B g PT8P PlBP
~TPA CONTENT CO~PONENT
1 0 CHRONA70GFU~ NTPA CONTENT VARIATION IN 190 CONTENT STA81LIZATL
SA~PLE ASPECT ASPECT A m R ICG~ PER RELATION TO 1~ RELATION ON FACTOR
No AFlER 7EST lESTNOR~ AT IOOS SPECI~EN TO SPECI~EN
1 1 Yellov vith dar~ hany co ponent~ ~1 3 - 11 6~/~1 29-0 282 1 00 precipitate 1 5 1 2 Yello~ hany co ponents 6~ 9 23 7 6 6516S 9/0 103 1 61 lless than - specieen 1 3 Yellov Nany co ponents 59 S lB l 8 36/59 ~-0 1~1 1 U
lless than 2 0 specie en~
2 1 Dar~ yellov hany co ponents 60 9 - 3 71/60 91-0 0611 1 00 2 2 Light yellov ~any co ponents 65 7 ~ 7~ 3 74165 6-0 0569 l lS
2 3 Light Yellov ~bny co ponents 68 ~ 7 51 1 7~/68 ~2-0 0255 1 2S
lless than 2 5 speciaen) 2~ 6 31~
2.~ :Very ligh yellw: Fe~ co ponents: 18.91 : 18.0 :1.57178.91-0.0199: 1.85 2.8 : Colorless :Fe~ co ponents: 82.8~ : 18.~ :0.646/82.8~-0.0078: 2.07 3.1 : Yello~ :Jbny co ponents: 56.7 : - :~.78/56.8-0.08U: 1.00 3.2 : Yellov :lbny co ponents: 70.5 : 13.1 :2.18/70.5-0.031 : 1.~6 3.3 : Light yelw to :Fe~l co-ponents: 77.7 : 20.9 : 1.99177.7-0.026: 1.9 : colorle~6 : : : : :
.1 : Dar} yellw :llany coeponents: 61.~ : - :7.65161.~-0.12~ : 1.00 .2 : Light yellw :Fe~ cwponents: 76.9 : 15.~ :2.2~/76.9~0.0291: 2.10 .3 : Light yellw to :Fe~r co ponents:78.6 : 17.2 : 3.11178.66-0.039: 2.27 1 0 : colorles6 6.1 : Yello~J :Ibny co ponents: 72.78 : - :12.66172.7-0.173: 1.00 6.3 : Colorless :Fe~ coyonents: 90.2 : 17.~ :2.99190.2-0.0253: 2.78 6.6 : 51ightly :Fe~l co~onentfi: 88.9 : 16.1 : 3.78/86.9-O.OU: 2.69 : yellw;sh 7.1 : Yellw :llany coeponents: 70.7 : nil : 1.3~M0.7-0.0618: 1.00 7.2 : Colorless :Fe~ co ponents: 89.8 : 19.2 :2.58/89.8-0.029 : 2.88 7.3 : Colorles~ :Fe~ co ponents: 91.9 : 21.2 :2.08/91.8-0.0266 : 3.60 7.5 : Light yellw :Fe~ cwponets: B7.8 : 17.1 :2.20/87.~0.0262 : 2.23 20 7.6 : llery light :Fe~l conponent6: 90.1 : 20.3 : 1.30/90.1-0.014 : 3.14 :yellw 7.11: Dar} yellw :Ibny conponents: 77.2 : 6.5 :3.38/77.2-0.0438 : 1.28 7.16: Yellw :llany co~onents: 78.3 : 7.6 : 2.~5178.3-0.0313: 1.30 7.14: Colorlefis :Fe~ cooponents: 90.2 : 19.5 : 2.03/90.2-0.022~: 2.99 : Colorless :Fe~l cooponents: gO.6 : 19.9 : 1.95190.6-0.0215: 3.11 W093/13059 PCT/BR92/~20 2~0379~ ` -~efore everything, addition of ascorbic acid ~lone, despite being capable of absorbing oxygen powerfully, is not indicated for stabilizing aldehydes, since as it is and acid it would catalyze aldol condensation reactions.
The synergic effect of A/B composition in MTPA
st~bilization as compared with application of substances individually is very clear, particularly amines such as pyridine, quinoline and dimethylaniline, as was done in the state of the art. Besides, amounts in the A/B
fitabiiizing sytem are lower than those recommended in the state of the art.
~tabilizer mass ratlos of 1000, 2000 and 2500 ppm and molar ratios of 10~, 20# and 50# of ascorbic acid in TEA
were tested for the stabilizing mixture. Triethanolamine is known to exhibit low toxidity, virtually no contribution to smell and a high boiling point ~206C at mm Hg), higher than MTPA, which positively recommends it for industrial h~ndling.
2) TEST WITH TEA/AA
Other more precise tests were carried out with the TEA/AA sta~ilizing system.
Samples wer~ prepared with mass and molar ratios as indicated below:
W093~13059 PCT/BR92/~020 ~ 937~
9.6 mg ascorbic acid (0.055 m mol) and 90.4 mg triethanolamine ~0.603 m mol) to 100 ml MTPA - actual molar ratio used: 8.4~ mol~r ascorbic acid to 91.6X
molar trieth~nolamine.
Tests were carried out at 50, 80 and lOO~C for heating periods of up to 360 hours t15 days).
Data obtained are shown in table 2, where each value is an average of two tegt repetitions with good relative accuracy. MTPA content wa~
determined by GC and oximation. By way of information, there are also included dat~ obtained at 50C for MTPA
oontact with carbon ste~l in the presence ~nd absence of a st~bilizing system.
BA~ n~T-~A-STABILI~
CO~IT10~ Tl~
67Hours SAtlPLES : : Reurks :: Results : . : Altehyte : GC
: : Aspect : ~Sl : ~S) :Stabilization : : Color : ~aueragel :~average) : Factor 2 5 HTPA : 50 : Colorless : 95.13 : 92.55 : I.OO
W O 93/13059 PC~r/B R92/0(H)20 2~37~
~IPA + Trlethanolaelne 50 Colorle~s 97 15 9~ 26 2 27 A~corblc Acid ~IPA 80 Light 79 2780 Il 1 00 yello~
S ~IPl t Trieth nola-ine 80 Colorle~s93 87 9~ 36 ~ 5 t A~cor~ic Acid ~TPA lO0 Dar~ 58 9169 83 1 00 yello~
~IPA ~ Ttiethanolad ne 100 Light 7~ 11 82 9~ 1 6 1 0 t A corbic Acid Yello~
~TPA ~ Ca~bon Steel 50 Colorle~t95 55 92 9~ 1 00 ~TPA t Car~on 5teel ~ 50 Colorles6 97 58 9~ 67 5 83 Trlethanolaeina ~worbic Acid BASE TEST - ~1PA - ST19ILIZERS
CONDITIONS TI~E
2 0 14~ Hwrs SA~PLES Re arks Re6ults Aldehyde GC
Aspect ISI l~ Stablll2Ation Color laverage~ laverage1 Factor 2 5 ~TPA 50 Colorless 89 7090 07 l 00 WO 93/13059 PCI'/BR92/00020 2~ ~7~
IITPA t Triothanolaeino 50 Colorle6s 97 59 93 ~8 B 30 t Ascorblc Aclt IllPl 80 Yello~ 68 39 ~3 16 100 IITP1 t TrlothanolaDine ôO Colorloss 86 ô7 88 80 2 66 t Ascotbic Acid lI`rP1 100 Yelloldsh ~l U 55 00 100 bro~m 16ticl~g~
I~PA t Triethanola~ine 100 Light 61 1576 38 15 t Ascorbic Acid yello~
IrlPA t Carbon 9teel 50 Colotless 92 3293 05 100 ISIPA t Carhon Steel t 50 Colorle6t 96 ~09~ 0ô 3 55 Trlethanola-ina t A~corbic Acid BISE TEST IITPl- STABILIZERS
CONDITIONS TIB
2~0 Hours SAIIPLES RQearks Results Aldehyde GC
Aspect ~S) ~51 Stabilization Colorla~eragel laveragel Factor lSlPA 50 Colorless 86 0283 58 100 IllPA t Trietbanola~ine 50 Colorless 96 89 9~ 07 11 09 t Ascorbic 1cid WO 93/~3059 PCI/BR92/00020 2i~379~
IlTPll : 80: Yello~ : 55.30 :63.13: 1.00 ItrPA t Trlethanolaelne: 80:Very : 79.55 : 83.5~: 2.31 t A~corbic Acld : : light : ~ello~ : ::
lilPl: 100: Yello~h: 30.22 :36.92: 1.00 : bro~m :
(sticky~ : : :
~IT.Pl t TriethanolaeiRc: 100:Ligh~ :52.5~ : 71.58: 1.~9 t A~corbic hid : : Yello~ : ::
111~1 t Carbon Steel : 50: Very : 91.52 : 92.21: 1.00 light yellw IIT.PA t Carbon Steel t: 50: Colorless: 95.95 : 93.00: 3.16Tricthanola~ine ~ :: : ::
Ascorbic Acid aAsE rEsr - llPA- STAalLlZERS
CONDITIONS TlIIE
360 Hours SAIIPLES : : Reurks: :Results : Aldehyde : GC
: A~pect : (S1 : (S~ :Stabillzation : Color : laverage~ :laverage~: ~actor llrPA : 50 : Colorless: 80.29 : 78.27: 1.00 WO 93/13059 PCI/BRg2/00020 3 7 9 ~
I~IPA ~ Trlcth~nol~ne 50 Colorloss 97 25 92 98: l7 71 t kcorblc Acld l~rPA : 80 Deep ~ 11 59 261.00 : Yello~l :
l~l~A t Triethanolaaine 80 l~ery 72 51 79 90 211 t Ascorbic lcid ligbt yello~
lllPA 100 Yello~dch 2~ ~6 29 23 1 00 bro~m I~t~clly~
IIIPA t Trlethanola lne: 100 Yellal ~ 02 56 39 1.36 t Ascotb1c Acid IrlPA t Carbon Steel 50 llery 89 56 88 ~0 1.00 light yello~
IrlPA t C rbon Steel t 50 Colorlecs 93 66 9163 195 Triethanola-ine t A6corbic Acid From Table ~, the efficient ~ehavior of this st~biIizing composition can be noticed. Thus, for MTPA with an 98.01~ initial content, it is noted that the content (dosed by oximation) is kept virtually unchanged at 97X
25 after a 15-day heating, while in the abs~nce of W093~13059 PCTtBR92/00020 2~ ~379~
sta~ilizer such content drops to 78X under the same thermal conditions.
The composition herein is effective for tabili2ing MTPA
at 50~C kept in contact with carbon steel.
PHY5 I CAL CHEM l CAL DATA ON ~3TAB I L I ZAT I ON:
Graph 1 s~ow~ the correlation of data in table ~, where in:
3TABILIZEI:) MTPA AT 50C
I I NON--STABILIZED MTPA AT 50C'C
V STABILIZED MTF'A AT 100C C
WO 93/13059 PCr/BR92/00020 38 2~7~
'~
1~ _ o . . . , . :._ 100 2 )0 O Tlme IH) WO93/1~59 PCT/BR92/~020 .
2~
It is noticed thht there is ~ first order kinetic variation between MTPA contents and time values for 50 and 30~C temperature~. At 100C the correlation is not linear, which ~ùggests ~n interference of mechanisms, particularly decomposition by heat, operating at this temperature and with little operation up to 80C.
The calculation of initial speed constants at the three - temperatures for non-~t~bilized and ~tabilized MTPA
leads to data in Table 3.
1'0 XINETIC DATA RELATIVE TO NON-STABILIZED AND ~TABIL~ZED
MTPA - ~PEED CON~TANT~ ~X) AT EACH TEMPERATURE
Teeperature ~ .tabilized : Stabilized I CI : '~A : IITPA*
: k ~hour~l, : kld~ (hour~l l K(d~
: 5.~xlO-~ ) : 1.3xlO t~ : 1.2xlO-' ): 2.9xlO'~) : 2.2x10-3 ) : 5.3xlO ~) : 3.7xlO'~): 8.~xlO-~) l~s~ : 5.3xlO 3 ) : 1.26xlO~1) : 1.2xlO 3 ): 3.0xlO ~) $ Stabilizer: 10~ molar Ascorbid Acid - Triethanol-amine at 1000 ppm.
W093/l3~9 PCT~BR92/~20 2 1 ~ 3 7 3 ~
4~J
l*~ The X value is that of the pseudo-first order in}tial speed con&tant calculated between times zero and 67 hours in Table 2.
As from table 3, the calculation of activation energies for the two situations leads to the following values:
Activ~tion energy - HTPA decomposition..10.5 Kcal~mol non-cta~ilized Activation energy - MTPA` decomposition..25~5 Xcal/mol stabilized Thus, kinetic~lly and thermodynamically, MTPA
stabilization with the TEA/AA st~ilizing composition is equiv~lent to an increase of two ~nd h~lf times in the magnitude of activation energy, which quantifies the degree to which this composition is Llocked ~y the presence of staLilizer.
An extrapolation of data in tables 2 and 3 according to correlation log X = f (1/T) for 30C ena~les calculation of speed constant at this temperature in K = 1.15 x 10-5 hour for sta~ilized aldehyde. This value mean~ a rate forecast for MTPA dropping le~s than lX for 1-month storage under environmental conditions in the presence of ~ta~ilizer.
ALDEHY~E ~ISTILLATION
W093/13059 PCT/B W2/0~20 2~
This test shows the mass distribution of TEA/AA
stabilizing components in MTPA distillation in its light, distillate and residue fractions. ~tabilizer monitoring wa~ conducted by following up TEA, since the AA high boiling point authorizes the assumption that this component remains in the distillation residue.
The test was carried out by discontinuous distillaton in a 5 cm outer diameter, 65 cm high glass column fitted with 7 Teflon pierced plates.
5.97 liter ~6210 9) MTPA at 90.0X recently distilled to which were added 5.5~ 9 ~990 ppm) TEA and 0.62 9 ~100 ppm) AA were distilled at 91C and 39 mm Hg. A light fraction equivalent to 18X of total, 3 consecutive destillate fractions ~ointly adding up to 77.7X mass and - a residue equivalent to 3.4% mass from total were collected.
TEA wa~ potentiometrically dosed in each fraction using 0.01 N pe-chloric acid in acetic acid as titrant.
Concurrently, blank tests were carried out in specimens, which showed that the TEA dosage limit under 7~
42.
such conditions is lO ppm. The results obtained are 6hown in table 4:
FRACTIONS
: Trietllanol-: Boiling : : Individual - : accuDlated : aeine Range at: Ib~ - t Content Fra¢tion : 39 ~ Hg : 19) S : S : ppe Llght :B~-91 : 110~ : 17.B 11.8 10 ~ t gl : 209~ 33.7 51.5 10 ~11Dt~
Il 91 : 2010 : 32.6 : 8~.1 : 10 II~
111 91 : 1B2 :12 5 : 96.6 10 ~ND1t Resldue - 220 : 3.~ - 100.0 26150 Heavy fro~ : : :
Flash 12112/90 : - : - - : - : < lO~liD) r Not detected by potentiometric dosage.
From the above table it is noted that all of TEA ~nder such conditions remains in the distillation residue, and therefore it is poscible to foresee that the components WO 93tl3059 PCI~/BR~2/00020 2~3rt9~
of the proposed stabilizing composition will remain in the residue even during continuous operation.
CAR~ON STEEL
1) LON~ DURATION TEST ON MTPA DECOMPOSITION: STABILIZING
ACTI~N IN AN INERT ATMOSPHERE, IN THE PRESENCE AND
A~SENCE ~F CARBON ~TEEL, AT 37C
A 120-day long test was carried out to determine HTPA
decomposition ~t 37 C~ in the presence and absence of carbon steel, and stabilizing syctem in an inert atmophere~
Tridistilled MTPA under N2 ~nd kept in N2) with a 100%
initial content was packed in glass ampoules, either containing or not containing carbon steel test peciments, in an N2 caturated atmosphere. A st~bilizing composition having 900 ppm TEA and 100 ppm AA was used.
From thc reults hown ln Tabele 3A below it is noticed that:
a) decomposition becomes important between 15 days and 1 month in storage at such temper~ture, which suggests a strong autocatalysis effect by decomposition products themselves.
b) st~bilizing effect of the system: an average 7X
decomposition in a 3-month storage as against a 17%
WO93/13059 PCT/BR92/~020 2~379i~
a~r~ge decompoæition for the non-stabilized product during the same period.
o~ MTPA stabilization in the pre~ence of carbon steel.
LONG DURATION TEST ON MTPA DECOHPOSITlON AND STABILIZING
ACTION IN AN INERT ATMOSPHERE. IN THE PRE~ENCE AND
ABSENCE OF CARBO _ 5TEEL - VALUE~ IN MTPA
: 3 days : 7 days : 15 days : Aug/27 : Aug/21 : Aug/29 : A~poule : HP U : A ploule : NP U : A poule : HPLC
: No. : Content : No. : Content : No. : Content : 1 : 97.89 : 9 : g7.06 : 17 : 96.8~
~JPl : 2 : 100.06 : 10 : 97.50 : 18 : 98.54 ~TPA t : 3 : 99.85 : 11 : 97.82 : 19 : 99.65 C~RBO~ : : : : : :
2 5STEEL : ~ : 98.24 : 12 : 101.77 : 20 : 95.81 W O 93~13C~59 PC~r/B R 92/CUD020 . ~ .
æ~37~3 45 HnPl ~ T.E.l.~ : 5 : 99.51 : 13 : 101.60 : 21 : 105.05 A.l. : 6 : 99.09 : 1~ : lOO.BI : 22 : 98.98 HTPA t T.E.A. : 7 : 99.18 : 15 : 97.69 : 23 : 99.50 A.A. t STEEL : 8 : 99.7~ : 16 : 101.18 : 2~ : 91.60 T ES;T A T 3 7 C
: 30 days : 4~ days : 62 d~ys : Sep/13 : Sepl27 : Oct/15 : A poule : HPLC : A poule : HP U : bpoule : HP U
1 0 : No. : Con~ent : No. : Content : No. : Content : 25 : 99.80 : 33 : 89.1~ : ~1 : 90.33 HIPA : : 95.~7 : : : : 90.38 : 26 : 95.57 : 3~ : 92.46 : ~2 : 89.90 H1PA t : 27 : 74.6~ : 35 : 69.7~ : U : 32.3 STEEL : 28 : 90.37 : 36 : 67.~2 : ~ : 71.96 ~TPA t T.E.A. : 29 : 97.69 : 37 : 97.36 : ~5 : 97.~5 t A.A. : 30 : 97.33 : 38 : 95.62 : ~6 : 96.08 NIPl t T.E.A. ~ : 31 : 97.93 : 39 : 88.68 : ~7 : 62.36 2 0 l.A. t STEEL : 32 : 96.98 : ~0 : 81.08 : 48 : 65.~1 : 76 days : 97 d~ys : 120 days 2 5 : Sep/29 : Nov/12 : Dec 12 ~a3~
4~.
:b~le: ~ :A~Ie : ~ : ~le : ~C
: Ho. :Content : No. :Content : No. :Con~ent ~A : ~9 : 9~.50 : 57 : 78.73 : 73 : 5~.66 : 50 : 90.62 : 58 ~ : 6'8.26 : 7~ : -~PAt : 51 : 56.36 : 59 : ~.66 : 75 : 15.93 CM~E~ : 52 : 37.09 : 60 : 11.82 : 76 : -~At : 53 : 96.~5 : 61 : 92.76 : 77 : ~.U
T.E.A.~A.A. : 5~ : Lro~en : 62 : 93.62 : 7~ : ~.12 -~PAtT.E.A.~ : 55 : 52.33 : 63 : 51.51 : 79 : U.66 1 0 A.A.~CA~H ~ L : 56 : Lro~n : 6~ : ~9.57 : ~ : 35.63 MTPA - distillation and redistillation on test preparation dàte.
Sample~ prep~red in nitrogen environment - inert 1 5 atmosphere.
Carbon ~teel 1OZ0 .
The method ued for determining MTPA content was dosage by liquid chromatography ~HPLC) through outer standardization.
2 0 Apparatus: HPLC - Varian 5 0 1 0 or similar.
Column: Lichro.or~ ~P 1 8 , length = ~0 cm, inner diameter = 0 . 4 cm.
Moving stage: acetronitrile/HZ0 , l:g v/v Discharge: 1 . ml/min.
2 5 ~etection: UV at 2 0 0 nm.
3~9~
4'7 ~ilution sf measured solution: O.lX in acetonitrile.
In~ection volume: lO ul.
Retention time: about 8 min.
Integrator: HP 3390.
Dosage by outside standardization: Th~ MTPA standard is obtained by bidistillation and conservation in N2 in a freezer, stabilized with 9OO ppm TEA and lOO ppm AA.
2~ MTPA BEHAVIOR lN THE PRESENCE OF COMMON OR STAINLESS
STEEL IN ACCORDANCE WITH TEMPERATUFE AND ACTION OF
STABILIZING SY5TEM.
The sarne procedure was uced, as already descri~ed under item 1) ~KINERGIC ACTION OF 5TABILIZING 5YSTEM"
hereinabove. MTPA dosage was made by oximation and also by gas chromatography and liquid chromatography (see aspect of chromatogram).
In tests carried out in the presence of carbon steel, test &pecimens of the material were placed inside ampoules, which then were sealed and heated for definite period. TEA~AA system was used at lOOO ppmm.
TABLE lA
2~ ~37Q~
4~'~
MTPA IN THE PRESENCE OF CA~BON STEEL - ACTION OF
TEA-AA STABILIZER
: : 72 hours : 11~ hours : 2~0 hours : 360 hours INITIAL NTPA : : :Aldebyde: : Aldehyde : :lldehyde: :Aldehyde ALDNYDE S = 90.1 :t : Aspect : S : Aspect : X : aspect: S : Aspect : S
NTPA :C: : :Colorless: 98.3 : : :Colorless: 97.5 NnPA t llEA - AA) : R: : :Colorless: 98.2 : : :CoJorless: 98.2 1 0 NIPA t CARBON STEEL: 0: : :Colorless: 97.2 : : :Light : 96.5 : : : :yello~ :
PA t 11EA - AA~ : ~: : : : : : : :
t CARBON STEEL : : : :Colorle u: 91.2 : : :Colorless: 97.3 ~TPA : :Colorless: 98.2 :Colorl ss: 97.7 :Colorless: 87.3 :Colorless: 77.6 1 5: :L~gb- : : : : Light NTPA t CARBON STEEL:50:Yello~ : 96.2 :yello~ : 92.2 :Yello~ : 81.3~Yello~ : 81.0 NTPA t ITEA - AAI
t CARBON STEEL : :tolorless: 97.3 :Colorlecs:95.9 :Colorless: 91.8:Colorless: 85.7 2 0 : : : : Slightly: : l~ght : : :
~TPl : :Colorless: 96.8 : Yell w : 90.5 : Yellov : 81.5:1elo~ : 65.5 : : Dark ~TPA t C~RSON STEEL:80: Yello~ : 60.1 :Greenish : 31.4 : Greenish: ll.l:Greenish : 6.4 2 5 NTPA t ITEA - AAI : : : : : : : : :
W O 93/13059 PC~rtB F~92/oH~020 21 937 9 ~
4~
t CARBO~ SIEEL lellov 85 6 Yello~ 75 5 ~ello~ 51 3 Greenish 34 7 : Orange Orange ~1PA :Colorle~ 88 6 Yello~ 68 7 ~ello~ ~2 5 ~ello~ 36 0 : :Gteenjsh: : : : : t S ~nPI t tARBOR STEEL lOO Yello~ 30 ~ 6reeni~h 17 3 Greeni~h 1 9 BroYn : 1 5 Pl t IIEA - AAI Bro~ni~
t CARB4~ STEEL ~elloY 66 7 Greenish 26 1 6reenish 22 0 YelloY 9 Light Light ~nPA : ~ello~ 10 0lello~ 53 0 1 0 ~TPA t ITEA - AA) R:Colorls~ 96 5 Colorlec~ 96 ~TPA t: 0 Light Light t CAR80~ StEEL : 0: Yello~ 95 S ~ello~ 92 9 ~TPA t ITEA - U~ ~
t CARIOR STE$L Colorle~s 97 B Colorle~ 96 5 The d~t~ in table lA above show the double effect of steel on MTPA:
. T ~ 50 C: the drop in MTPA content and rate of formation of impurities, noticed via chromatogram, is con~-iderably reduced when in contact with carbon steel, as compared with MTPA alone t39.9~ absolute difference in content values at room temperature).
At room temperature MTPA content is the same in the 2 5 presence or absence of carbon steel, under the action of 21~37~
so stabilizer after 1080 hours (45 days).
T ~ 50C: ~teel ha a strong positive effect on ~ldehyde decomposition. Experimentally it i~ noted that~
after 360 hours at 80C the MTPA content in the presence of carbon steel is 6.4%, while MTPA content when placed under the fiame heat conditions for the fiame period is 65.5%. At 100C the effect is even more ~trongly marked.
Under suc~ conditions, stabilizer decomposition i~
efficient at 80 C. Stabilized MTPA content exhibits a higher value th~n non-stabilized MTPA when in the presence of car~on steel.
Therefore, the conclusion is that the sta~ilizer is efficient to ~lock S-fiubstituted aldehyde decomposition at varying temperatures in the presence of carbon ~.teel.
WATER
1) MTPA decomposition test at 50 and 80~ C in the presence of growing water contents and 1000 ppm of gOX
TEAT - lOX AA mixture.
WO93/13059 PCT~BR92/~020 2~ 6 Samples we~e analysed fo~ MTPA content by hig~
resolution liquid chromatography ~HPLC) under already descr~bed conditions.
Ta~le 2A shows the negative effect of water on sta~ilization at te~ted temperatures:
MTPA ~ECOMPO~ITION AT 5 0C AND 8 0 C IN TE PRE~ENCE OF
GROWING WATER CONTENT~ AND lOOO PPM OF 9O%
TRIETHANOLAMINE - lO% ASCORBIC ACID MIXTURE
MTPA CONTENT
: 7day~ : 13days : 28days 1 5 ~At~pp~0 : 99.6$ :98.3S : 9B.65%
: 98.7t :91.5S : 96.7S
~At250ppa~0tTEA : 96.5t :9~.~S : 89.~%
tA.A.l1000pp~ : 97.8S :96.S : 91.0S
~A t 350pp~0tT.E.A. : 97.3S :19.6S : 92.9%
2 0 A.l. 11000pp~1 : 99.9S : - `: 91.5S
~At125~p~H20t ~A : 99.5S :95.~ : 8i.
+A.A.(lOOOpp~l : 99.8S :92.~S : 89.7S
~PAt250pp~0 : 93.3S :97.2S : 6~.3%
: 85.9S :85.5S : S9~S
2 5 ~At2~pp- ~0tTEA : 65.0S :19.~S : 32.2%
WQ93/13~9 PCT/BR92/~20 ._ !
21~37~ ' 5` t A.A. IlOOOpp~) : 71.5S : 19.~S : 21.95 ~A~3~ t~ : 65.0S : 19.6S : 2~.~%
~A.1.~10~pp~ : S~.OS : 19.9S : ~.6S
~PA~ pp~ : 10.6S : 18.1$ : 23.6X
~A.A.IIO~pp~) : 65.~ : ~.5S : 21.3S
- Initital MTPA content: 100.0#
- TEA - Trithanolamine ~900 ppm); A.A.- Asaorbic Acid ~lOOppm).
I0 - HPLC dosage by ouside standardization.
- Test carried out in nitrogen.
The v~lues. indicated correspond to two tests carried out concorrently.
2) MTPA decomposition test at 50C in the presence of 1000 ppm water and lO00 ppm of ~0~ pyridine - 10%
ascorbic acid stabilizing mixture.
As in the previous test, samples were analysed for MTPA
content by chromatographic analys~s under already described conditions. The effect of water and steel on MTPA is thuc noted (table 4A).
WO93/13059 PCT/BR92/~020 21~3~
5~.
MTPA DECOMPO~ITION AT 50~C IN THE PRESENCE OF lOOO PPM
OF WATER AND lOO0 PPM OF 9O# PYRIDlNE - lO# ASCOR81C
ACID MIXTURE.
MTPA CONTENT
: l~days : 27day~ : Uaays l~rPA Speci~en :92.6S : 93.1S : 8~.6 99.5S : 97. IS : 82.2S
~IPA t py t A.A. 11000 : 98.6S : 92.95 : 91.6%
pp~ t lOOOpp~ 0 :IOI.IS : 95.2S : 93.3S
~AtCM~ ~ L :96.5S : 92.SS : 39.7X
: - : 7l.7S : 39.1S
IrrPA t CA~ON STEEL t : 98.8S : 5~.1S : 16.5X
py t A.A tlOOOpp-~ t lOOOpp- H20 : 93.3S
- MTPA initi~l cc,ntent tHPLC): 100.0:~%.
- .py tPyridine ~t ~OOppm): A.A. tA~cor~ic Acid ~t 100ppm).
W093/13059 PCT/BR92/~020 21037~
. 54 - Te~t carr~ed out under nltrogen.
Test ind~cated corre6ponet to te~t~ carrled out concurrently.
TEA wa~ potentiometrically dosed in each fraction using 0.01 N pe-chloric acid in acetic acid as titrant.
Concurrently, blank tests were carried out in specimens, which showed that the TEA dosage limit under 7~
42.
such conditions is lO ppm. The results obtained are 6hown in table 4:
FRACTIONS
: Trietllanol-: Boiling : : Individual - : accuDlated : aeine Range at: Ib~ - t Content Fra¢tion : 39 ~ Hg : 19) S : S : ppe Llght :B~-91 : 110~ : 17.B 11.8 10 ~ t gl : 209~ 33.7 51.5 10 ~11Dt~
Il 91 : 2010 : 32.6 : 8~.1 : 10 II~
111 91 : 1B2 :12 5 : 96.6 10 ~ND1t Resldue - 220 : 3.~ - 100.0 26150 Heavy fro~ : : :
Flash 12112/90 : - : - - : - : < lO~liD) r Not detected by potentiometric dosage.
From the above table it is noted that all of TEA ~nder such conditions remains in the distillation residue, and therefore it is poscible to foresee that the components WO 93tl3059 PCI~/BR~2/00020 2~3rt9~
of the proposed stabilizing composition will remain in the residue even during continuous operation.
CAR~ON STEEL
1) LON~ DURATION TEST ON MTPA DECOMPOSITION: STABILIZING
ACTI~N IN AN INERT ATMOSPHERE, IN THE PRESENCE AND
A~SENCE ~F CARBON ~TEEL, AT 37C
A 120-day long test was carried out to determine HTPA
decomposition ~t 37 C~ in the presence and absence of carbon steel, and stabilizing syctem in an inert atmophere~
Tridistilled MTPA under N2 ~nd kept in N2) with a 100%
initial content was packed in glass ampoules, either containing or not containing carbon steel test peciments, in an N2 caturated atmosphere. A st~bilizing composition having 900 ppm TEA and 100 ppm AA was used.
From thc reults hown ln Tabele 3A below it is noticed that:
a) decomposition becomes important between 15 days and 1 month in storage at such temper~ture, which suggests a strong autocatalysis effect by decomposition products themselves.
b) st~bilizing effect of the system: an average 7X
decomposition in a 3-month storage as against a 17%
WO93/13059 PCT/BR92/~020 2~379i~
a~r~ge decompoæition for the non-stabilized product during the same period.
o~ MTPA stabilization in the pre~ence of carbon steel.
LONG DURATION TEST ON MTPA DECOHPOSITlON AND STABILIZING
ACTION IN AN INERT ATMOSPHERE. IN THE PRE~ENCE AND
ABSENCE OF CARBO _ 5TEEL - VALUE~ IN MTPA
: 3 days : 7 days : 15 days : Aug/27 : Aug/21 : Aug/29 : A~poule : HP U : A ploule : NP U : A poule : HPLC
: No. : Content : No. : Content : No. : Content : 1 : 97.89 : 9 : g7.06 : 17 : 96.8~
~JPl : 2 : 100.06 : 10 : 97.50 : 18 : 98.54 ~TPA t : 3 : 99.85 : 11 : 97.82 : 19 : 99.65 C~RBO~ : : : : : :
2 5STEEL : ~ : 98.24 : 12 : 101.77 : 20 : 95.81 W O 93~13C~59 PC~r/B R 92/CUD020 . ~ .
æ~37~3 45 HnPl ~ T.E.l.~ : 5 : 99.51 : 13 : 101.60 : 21 : 105.05 A.l. : 6 : 99.09 : 1~ : lOO.BI : 22 : 98.98 HTPA t T.E.A. : 7 : 99.18 : 15 : 97.69 : 23 : 99.50 A.A. t STEEL : 8 : 99.7~ : 16 : 101.18 : 2~ : 91.60 T ES;T A T 3 7 C
: 30 days : 4~ days : 62 d~ys : Sep/13 : Sepl27 : Oct/15 : A poule : HPLC : A poule : HP U : bpoule : HP U
1 0 : No. : Con~ent : No. : Content : No. : Content : 25 : 99.80 : 33 : 89.1~ : ~1 : 90.33 HIPA : : 95.~7 : : : : 90.38 : 26 : 95.57 : 3~ : 92.46 : ~2 : 89.90 H1PA t : 27 : 74.6~ : 35 : 69.7~ : U : 32.3 STEEL : 28 : 90.37 : 36 : 67.~2 : ~ : 71.96 ~TPA t T.E.A. : 29 : 97.69 : 37 : 97.36 : ~5 : 97.~5 t A.A. : 30 : 97.33 : 38 : 95.62 : ~6 : 96.08 NIPl t T.E.A. ~ : 31 : 97.93 : 39 : 88.68 : ~7 : 62.36 2 0 l.A. t STEEL : 32 : 96.98 : ~0 : 81.08 : 48 : 65.~1 : 76 days : 97 d~ys : 120 days 2 5 : Sep/29 : Nov/12 : Dec 12 ~a3~
4~.
:b~le: ~ :A~Ie : ~ : ~le : ~C
: Ho. :Content : No. :Content : No. :Con~ent ~A : ~9 : 9~.50 : 57 : 78.73 : 73 : 5~.66 : 50 : 90.62 : 58 ~ : 6'8.26 : 7~ : -~PAt : 51 : 56.36 : 59 : ~.66 : 75 : 15.93 CM~E~ : 52 : 37.09 : 60 : 11.82 : 76 : -~At : 53 : 96.~5 : 61 : 92.76 : 77 : ~.U
T.E.A.~A.A. : 5~ : Lro~en : 62 : 93.62 : 7~ : ~.12 -~PAtT.E.A.~ : 55 : 52.33 : 63 : 51.51 : 79 : U.66 1 0 A.A.~CA~H ~ L : 56 : Lro~n : 6~ : ~9.57 : ~ : 35.63 MTPA - distillation and redistillation on test preparation dàte.
Sample~ prep~red in nitrogen environment - inert 1 5 atmosphere.
Carbon ~teel 1OZ0 .
The method ued for determining MTPA content was dosage by liquid chromatography ~HPLC) through outer standardization.
2 0 Apparatus: HPLC - Varian 5 0 1 0 or similar.
Column: Lichro.or~ ~P 1 8 , length = ~0 cm, inner diameter = 0 . 4 cm.
Moving stage: acetronitrile/HZ0 , l:g v/v Discharge: 1 . ml/min.
2 5 ~etection: UV at 2 0 0 nm.
3~9~
4'7 ~ilution sf measured solution: O.lX in acetonitrile.
In~ection volume: lO ul.
Retention time: about 8 min.
Integrator: HP 3390.
Dosage by outside standardization: Th~ MTPA standard is obtained by bidistillation and conservation in N2 in a freezer, stabilized with 9OO ppm TEA and lOO ppm AA.
2~ MTPA BEHAVIOR lN THE PRESENCE OF COMMON OR STAINLESS
STEEL IN ACCORDANCE WITH TEMPERATUFE AND ACTION OF
STABILIZING SY5TEM.
The sarne procedure was uced, as already descri~ed under item 1) ~KINERGIC ACTION OF 5TABILIZING 5YSTEM"
hereinabove. MTPA dosage was made by oximation and also by gas chromatography and liquid chromatography (see aspect of chromatogram).
In tests carried out in the presence of carbon steel, test &pecimens of the material were placed inside ampoules, which then were sealed and heated for definite period. TEA~AA system was used at lOOO ppmm.
TABLE lA
2~ ~37Q~
4~'~
MTPA IN THE PRESENCE OF CA~BON STEEL - ACTION OF
TEA-AA STABILIZER
: : 72 hours : 11~ hours : 2~0 hours : 360 hours INITIAL NTPA : : :Aldebyde: : Aldehyde : :lldehyde: :Aldehyde ALDNYDE S = 90.1 :t : Aspect : S : Aspect : X : aspect: S : Aspect : S
NTPA :C: : :Colorless: 98.3 : : :Colorless: 97.5 NnPA t llEA - AA) : R: : :Colorless: 98.2 : : :CoJorless: 98.2 1 0 NIPA t CARBON STEEL: 0: : :Colorless: 97.2 : : :Light : 96.5 : : : :yello~ :
PA t 11EA - AA~ : ~: : : : : : : :
t CARBON STEEL : : : :Colorle u: 91.2 : : :Colorless: 97.3 ~TPA : :Colorless: 98.2 :Colorl ss: 97.7 :Colorless: 87.3 :Colorless: 77.6 1 5: :L~gb- : : : : Light NTPA t CARBON STEEL:50:Yello~ : 96.2 :yello~ : 92.2 :Yello~ : 81.3~Yello~ : 81.0 NTPA t ITEA - AAI
t CARBON STEEL : :tolorless: 97.3 :Colorlecs:95.9 :Colorless: 91.8:Colorless: 85.7 2 0 : : : : Slightly: : l~ght : : :
~TPl : :Colorless: 96.8 : Yell w : 90.5 : Yellov : 81.5:1elo~ : 65.5 : : Dark ~TPA t C~RSON STEEL:80: Yello~ : 60.1 :Greenish : 31.4 : Greenish: ll.l:Greenish : 6.4 2 5 NTPA t ITEA - AAI : : : : : : : : :
W O 93/13059 PC~rtB F~92/oH~020 21 937 9 ~
4~
t CARBO~ SIEEL lellov 85 6 Yello~ 75 5 ~ello~ 51 3 Greenish 34 7 : Orange Orange ~1PA :Colorle~ 88 6 Yello~ 68 7 ~ello~ ~2 5 ~ello~ 36 0 : :Gteenjsh: : : : : t S ~nPI t tARBOR STEEL lOO Yello~ 30 ~ 6reeni~h 17 3 Greeni~h 1 9 BroYn : 1 5 Pl t IIEA - AAI Bro~ni~
t CARB4~ STEEL ~elloY 66 7 Greenish 26 1 6reenish 22 0 YelloY 9 Light Light ~nPA : ~ello~ 10 0lello~ 53 0 1 0 ~TPA t ITEA - AA) R:Colorls~ 96 5 Colorlec~ 96 ~TPA t: 0 Light Light t CAR80~ StEEL : 0: Yello~ 95 S ~ello~ 92 9 ~TPA t ITEA - U~ ~
t CARIOR STE$L Colorle~s 97 B Colorle~ 96 5 The d~t~ in table lA above show the double effect of steel on MTPA:
. T ~ 50 C: the drop in MTPA content and rate of formation of impurities, noticed via chromatogram, is con~-iderably reduced when in contact with carbon steel, as compared with MTPA alone t39.9~ absolute difference in content values at room temperature).
At room temperature MTPA content is the same in the 2 5 presence or absence of carbon steel, under the action of 21~37~
so stabilizer after 1080 hours (45 days).
T ~ 50C: ~teel ha a strong positive effect on ~ldehyde decomposition. Experimentally it i~ noted that~
after 360 hours at 80C the MTPA content in the presence of carbon steel is 6.4%, while MTPA content when placed under the fiame heat conditions for the fiame period is 65.5%. At 100C the effect is even more ~trongly marked.
Under suc~ conditions, stabilizer decomposition i~
efficient at 80 C. Stabilized MTPA content exhibits a higher value th~n non-stabilized MTPA when in the presence of car~on steel.
Therefore, the conclusion is that the sta~ilizer is efficient to ~lock S-fiubstituted aldehyde decomposition at varying temperatures in the presence of carbon ~.teel.
WATER
1) MTPA decomposition test at 50 and 80~ C in the presence of growing water contents and 1000 ppm of gOX
TEAT - lOX AA mixture.
WO93/13059 PCT~BR92/~020 2~ 6 Samples we~e analysed fo~ MTPA content by hig~
resolution liquid chromatography ~HPLC) under already descr~bed conditions.
Ta~le 2A shows the negative effect of water on sta~ilization at te~ted temperatures:
MTPA ~ECOMPO~ITION AT 5 0C AND 8 0 C IN TE PRE~ENCE OF
GROWING WATER CONTENT~ AND lOOO PPM OF 9O%
TRIETHANOLAMINE - lO% ASCORBIC ACID MIXTURE
MTPA CONTENT
: 7day~ : 13days : 28days 1 5 ~At~pp~0 : 99.6$ :98.3S : 9B.65%
: 98.7t :91.5S : 96.7S
~At250ppa~0tTEA : 96.5t :9~.~S : 89.~%
tA.A.l1000pp~ : 97.8S :96.S : 91.0S
~A t 350pp~0tT.E.A. : 97.3S :19.6S : 92.9%
2 0 A.l. 11000pp~1 : 99.9S : - `: 91.5S
~At125~p~H20t ~A : 99.5S :95.~ : 8i.
+A.A.(lOOOpp~l : 99.8S :92.~S : 89.7S
~PAt250pp~0 : 93.3S :97.2S : 6~.3%
: 85.9S :85.5S : S9~S
2 5 ~At2~pp- ~0tTEA : 65.0S :19.~S : 32.2%
WQ93/13~9 PCT/BR92/~20 ._ !
21~37~ ' 5` t A.A. IlOOOpp~) : 71.5S : 19.~S : 21.95 ~A~3~ t~ : 65.0S : 19.6S : 2~.~%
~A.1.~10~pp~ : S~.OS : 19.9S : ~.6S
~PA~ pp~ : 10.6S : 18.1$ : 23.6X
~A.A.IIO~pp~) : 65.~ : ~.5S : 21.3S
- Initital MTPA content: 100.0#
- TEA - Trithanolamine ~900 ppm); A.A.- Asaorbic Acid ~lOOppm).
I0 - HPLC dosage by ouside standardization.
- Test carried out in nitrogen.
The v~lues. indicated correspond to two tests carried out concorrently.
2) MTPA decomposition test at 50C in the presence of 1000 ppm water and lO00 ppm of ~0~ pyridine - 10%
ascorbic acid stabilizing mixture.
As in the previous test, samples were analysed for MTPA
content by chromatographic analys~s under already described conditions. The effect of water and steel on MTPA is thuc noted (table 4A).
WO93/13059 PCT/BR92/~020 21~3~
5~.
MTPA DECOMPO~ITION AT 50~C IN THE PRESENCE OF lOOO PPM
OF WATER AND lOO0 PPM OF 9O# PYRIDlNE - lO# ASCOR81C
ACID MIXTURE.
MTPA CONTENT
: l~days : 27day~ : Uaays l~rPA Speci~en :92.6S : 93.1S : 8~.6 99.5S : 97. IS : 82.2S
~IPA t py t A.A. 11000 : 98.6S : 92.95 : 91.6%
pp~ t lOOOpp~ 0 :IOI.IS : 95.2S : 93.3S
~AtCM~ ~ L :96.5S : 92.SS : 39.7X
: - : 7l.7S : 39.1S
IrrPA t CA~ON STEEL t : 98.8S : 5~.1S : 16.5X
py t A.A tlOOOpp-~ t lOOOpp- H20 : 93.3S
- MTPA initi~l cc,ntent tHPLC): 100.0:~%.
- .py tPyridine ~t ~OOppm): A.A. tA~cor~ic Acid ~t 100ppm).
W093/13059 PCT/BR92/~020 21037~
. 54 - Te~t carr~ed out under nltrogen.
Test ind~cated corre6ponet to te~t~ carrled out concurrently.
Claims (10)
1) STABILIZING COMPOSITION FOR S-SUBSTITUTED ALDEHYDES
WITH THE GENERAL FORMULA (I):
having 4-15 carbon atoms, where:
R1 = C1-C5 alkyl, C6-C9 aryl, furfuryl, benzyl R2 = H, R1 R3 = H, R1 characterized by being based on a prototropic agent (A) in association with an O2 abstracting agent (B).
WITH THE GENERAL FORMULA (I):
having 4-15 carbon atoms, where:
R1 = C1-C5 alkyl, C6-C9 aryl, furfuryl, benzyl R2 = H, R1 R3 = H, R1 characterized by being based on a prototropic agent (A) in association with an O2 abstracting agent (B).
2) STABILIZING COMPOSITION FOR S-SUBSTITUTED ALDEHYDES
according to claim 1, characterized by the fact that component (A) is selected among . aromatic or heterocyclic aromatic amines, such as pyridine, dimethylaniline, quinoline, 8-hydroxyquinoline;
. alcanolamines or cyclic non-aromatic alcanolamines, such as triethanolamine (TEA), N-methylmorpholine;
. lactams, such as N-methylpyrrolidone;
and component (B) selected among . substituted phenols or hydroquinones, such as p-t-butyl phenol (PTBP), BHT (2,6-ditertbutyl,4-methylphenol);
. acid or unsaturated antioxidant agents, as ascorbic acid (AA) or beta-carotene;
except for compositions A/B = pyridine/PTBP and quinoline/PTBP.
according to claim 1, characterized by the fact that component (A) is selected among . aromatic or heterocyclic aromatic amines, such as pyridine, dimethylaniline, quinoline, 8-hydroxyquinoline;
. alcanolamines or cyclic non-aromatic alcanolamines, such as triethanolamine (TEA), N-methylmorpholine;
. lactams, such as N-methylpyrrolidone;
and component (B) selected among . substituted phenols or hydroquinones, such as p-t-butyl phenol (PTBP), BHT (2,6-ditertbutyl,4-methylphenol);
. acid or unsaturated antioxidant agents, as ascorbic acid (AA) or beta-carotene;
except for compositions A/B = pyridine/PTBP and quinoline/PTBP.
3) STABILIZING COMPOSITION FOR S-SUBSTITUTED ALDEHYDES
according to claims 1 and 2, characterized by the fact that the composition is preferably (A) TEA / (B) AA.
according to claims 1 and 2, characterized by the fact that the composition is preferably (A) TEA / (B) AA.
4) STABILIZING CONPOSITION FOR S-SUBSTITUTED ALDEHYDES
according to any of the previous claims, characterized by the fact that it is added in an amount of 500 - 1500 ppm, preferably in an amount 1000 ppm.
according to any of the previous claims, characterized by the fact that it is added in an amount of 500 - 1500 ppm, preferably in an amount 1000 ppm.
5) STABILIZING COMPOSTION FOR S-SUBSTITUTED ALDEHYDES
according to claim 4, characterized by the fact that the molar ratio between components (A)/(B) is comporised between 5/95 - 50/50.
according to claim 4, characterized by the fact that the molar ratio between components (A)/(B) is comporised between 5/95 - 50/50.
6) STABILIZATION PROCESS FOR S-SUBSTITUED ALIPHATIC
ALDEHYDES OF FORMULA (I), characterized by the fact the stabilizing composition (A)/(B) is added as described in claims 1 - 5.
ALDEHYDES OF FORMULA (I), characterized by the fact the stabilizing composition (A)/(B) is added as described in claims 1 - 5.
7) STABILIZATION PROCESS FOR S-SUBSTITUTED ALIPHATIC
ALDEHYDES OF FORMULA (I), according to claim 6, characterized by the fact the aldehyde is anhydrous or contains an amount of water lower than 300 ppm, preferably lower than 100 ppm, for stabilization temperatures up to 50°C.
ALDEHYDES OF FORMULA (I), according to claim 6, characterized by the fact the aldehyde is anhydrous or contains an amount of water lower than 300 ppm, preferably lower than 100 ppm, for stabilization temperatures up to 50°C.
8) STABILIZATION PROCESS FOR S-SUBSTITUTED ALDEHYDES OF
FORMULA (I), according to claims 6 or 7, characterized by the fact that the temperature to which the aldehyde is subjected is 25-100°C.
FORMULA (I), according to claims 6 or 7, characterized by the fact that the temperature to which the aldehyde is subjected is 25-100°C.
9) STABILIZATION PROCESS FOR S-SUBSTITUTED ALDEHYDES OF
FORMULA (I), according to claims 6 to 8, characterized by the fact that the aldehyde is in contact with carbon steel.
FORMULA (I), according to claims 6 to 8, characterized by the fact that the aldehyde is in contact with carbon steel.
10) ALIPHATIC S-SUBSTITUTED ALDEHYDE OF THE GENERAL
FORMULA (I):
having 4-15 carbon atoms, where:
R2 = C2-C5 alkyl, C6-C9 aryl, furfuryl, benzyl;
R2 = H, R1;
R3 = H, R1.
characterized by the fact. that it contains an A/B
stabilizing composition as described in claims 1 to 5 or that is stabilized according to process described in claims 6 to 9.
FORMULA (I):
having 4-15 carbon atoms, where:
R2 = C2-C5 alkyl, C6-C9 aryl, furfuryl, benzyl;
R2 = H, R1;
R3 = H, R1.
characterized by the fact. that it contains an A/B
stabilizing composition as described in claims 1 to 5 or that is stabilized according to process described in claims 6 to 9.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| BR9105694 | 1991-12-26 | ||
| BR919105694A BR9105694A (en) | 1991-12-26 | 1991-12-26 | STABILIZING COMPOSITION FOR S-SUBSTITUTED ALDEHYDE, STABILIZATION PROCESS OF STABILIZED ALDEHYDE |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2103796A1 true CA2103796A1 (en) | 1993-06-27 |
Family
ID=4053491
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA 2103796 Abandoned CA2103796A1 (en) | 1991-12-26 | 1992-12-22 | Stabilizing composition for s-substituted aldehydes, process for stabilizing aldehydes and stabilized aldehydes |
Country Status (6)
| Country | Link |
|---|---|
| JP (1) | JPH06506001A (en) |
| CN (1) | CN1077708A (en) |
| BR (1) | BR9105694A (en) |
| CA (1) | CA2103796A1 (en) |
| MX (1) | MX9207585A (en) |
| WO (1) | WO1993013059A1 (en) |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE19735332A1 (en) * | 1997-08-14 | 1999-02-18 | Degussa | Aliphatic alkanals with improved storage stability and process for improving storage stability |
| EP2813489A1 (en) * | 2013-06-11 | 2014-12-17 | Evonik Degussa GmbH | Method for the preparation of storage-stable 3-methylmercaptopropionaldehyde |
| EP3339290B1 (en) * | 2016-12-22 | 2019-06-19 | Evonik Degussa GmbH | Storage of 3-methylthiopropionaldehyde and methyl mercaptan |
| CN107903197B (en) * | 2017-12-22 | 2018-12-14 | 蓝星安迪苏南京有限公司 | The stabilizer for preparing and storing for 3- methylthiopropionaldehyde |
| EP3656760A1 (en) | 2018-11-21 | 2020-05-27 | Evonik Operations GmbH | Storage stable form of 3-methylthiopropionaldehyde |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| NL302251A (en) * | 1963-01-28 | 1965-10-11 | ||
| US4414419A (en) * | 1979-02-12 | 1983-11-08 | Ruhrchemie Aktiengesellschaft | Stabilization of aldehydes |
| US4546205A (en) * | 1982-06-16 | 1985-10-08 | Pennwalt Corporation | Stabilization of aldehydes |
| EP0148648B2 (en) * | 1984-01-04 | 1995-01-18 | Shin-Etsu Chemical Co., Ltd. | A method for stabilizing aliphatic higher aldehyde compounds |
-
1991
- 1991-12-26 BR BR919105694A patent/BR9105694A/en not_active Application Discontinuation
-
1992
- 1992-12-22 JP JP5511322A patent/JPH06506001A/en active Pending
- 1992-12-22 WO PCT/BR1992/000020 patent/WO1993013059A1/en active Application Filing
- 1992-12-22 CA CA 2103796 patent/CA2103796A1/en not_active Abandoned
- 1992-12-26 CN CN 92115231 patent/CN1077708A/en active Pending
- 1992-12-28 MX MX9207585A patent/MX9207585A/en unknown
Also Published As
| Publication number | Publication date |
|---|---|
| JPH06506001A (en) | 1994-07-07 |
| WO1993013059A1 (en) | 1993-07-08 |
| CN1077708A (en) | 1993-10-27 |
| MX9207585A (en) | 1994-06-30 |
| BR9105694A (en) | 1993-06-29 |
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