Note: Descriptions are shown in the official language in which they were submitted.
CA 02017126 1999-09-03
NOVEL REACTION PRODUCTS OF AMINOALKYLENE POLYCARBOXYLIC
ACIDS WITH SECONDARY AMINES AND MIDDLE DISTILLATE
COMPOSITIONS CONTAINING THE AFORESAID
BACKGROUND OF THE INVENTION
The present invention deals with novel reaction
products of aminoalkylene carboxylic acids with secondary
long chain amines as well as middle distillates containing
these reaction products, which have an improved low
temperature flowability and are able to better disperse
precipitated paraffin crystals.
Middle distillates such as, for example, gas
oils, diesel oils, or heating oils, which are derived from
the distillation of petroleum oils, contain different
amounts of paraffins depending on the source of the crude
oil. At lower temperatures solid paraffins settle out
(cloud point,CP). When further cooled, the plate shaped n-
paraffin crystals form a Kcard-house structure» and the
middle distillate congeals, although the majority of the
middle distillate is still liquid. The flowability of the
petroleum oil distillate fuel and/or fuel is substantially
impaired by the precipitated n-paraffins in the temperature
range between the cloud point and pour point. The paraffin
plugs up filters and causes non-uniform or completely
interrupted fuel feed to the combustion units. Similar
problems occur with heating oils.
1
CA 02017126 1999-09-03
FIELD OF THE INVENTION
It has long been known to modify the crystal
growth of paraffins in petroleum oil distillate fuel and
fuels by suitable additives. Effective additives on one
hand prevent the middle distillates from forming such card-
house structures, and they prevent solidification at
temperatures several degrees Celsius below the temperature
at which the first paraffin crystals settle out.
Furthermore they form, fine, well crystallized, separate
paraffin crystals which pass through filters in motor
vehicles and heating units or at least form a filter cake
permeable for the liquid portion of the middle distillates
so that problem-free operation is ensured.
A disadvantage of the aforesaid state-of-the-art
is that the paraffin crystals settle out, due to their
higher density compared to the liquid portion, and tend to
accumulate on the bottom of the tank when stored. In turn,
a homogeneous paraffin-free-phase forms in the upper
portion of the tank and on the bottom of the tank a duel
phase paraffin-rich-layer forms. Since both in fuel tanks
as well as in storage or delivery tanks of the mineral oil
dealer, the middle distillate is more often than not
withdrawn just above the tank floor, there is the danger
that the high concentration of solid paraffins will lead to
the plugging up of filters and metering equipment. This
danger increases all the more as the storage temperature
goes below the precipitation temperature of the paraffin
(cloud point) since the amount of separated paraffin is
2
CA 02017126 1999-09-03
represents a function of temperature and increases with
decreasing temperature.
Paraffin crystal modifiers, the so called flow
improvers, are polymers which alter the crystal growth of
n-paraffins by co-crystallization (interaction). Thus the
flow properties of a middle distillate are positively
influenced at lower temperatures. The effectiveness of the
flow improver is expressed indirectly by measuring the
«Cold Filters Plugging Points» (CFPP) according to DIN
51428.
DESCRIPTION OF THE RELATED ART
Low temperature flow improvers are conventional
ethylene copolymers, especially copolymers of ethylene and
unsaturated esters . DE 11 47 799 and 19 14 756 disclose,
for example, copolymers of ethylene with vinyl acetate
comprising from 25 to 45 weight percent of vinyl acetate or
vinyl propionate having a molecular weight of from 500 to
5,000.
GB 2 095 698 also discloses adding a combination
of the aforesaid copolymers with amides of long chain
amines and aromatic and cycloaliphatic carboxylic acids to
the middle distillates.
However, these mixtures are unsatisfactory with
respect
3
2017126
to the dispersing properties of the paraffins settled out.
The object of the present invention, therefore, is
to present additives to middle distillates which would have
an improved paraffin dispersing effect with good flow
improvement.
This object is met with a middle distillate
composition comprising a hydrocarbon mixture boiling between
160° and 420°C and a minor amount of amides, amide ammonium
salts, ammonium salts and their mixtures of aminoalkylene
l0 polycarboxylic acids having general structural formula I or
II:
(ACOCH2)2N-X-N-(CH2-COA) (I)
N(CH2COA)3 (II)
whereby X is a straight chain or branched alkylene radical
having 2 to 6 carbon atoms or the following radical:
20 --f-CH2~N--.~CH2~
CH2COA
whereby A is an hydroxyl radical or the following radical:
R
- N
R
in which R, independent from one another, are straight chain
30 aliphatic radicals having l0 to 3o carbon atoms.
4
2017126
The amide and/or amide ammonium salts and/or
ammonium salts, for example, of nitrilotriacetic acid, of
ethylene diamine tetraacetic acid or 1,2-propylene diamine
tetra-acetic acid are obtained by reacting the acids with from
0.5 to 1.5 moles of amine, more preferably 0.8 to 1,2 moles
amine per carboxyl group.
The reaction temperatures are from about 80° to
200°C whereby when preparing the amides the water resulting
from the reaction is continuously removed. The reaction need
l0 not be carried out completely to the amide, and moreover from
0 to 100 mole percent of the amine used can be present in the
form of the ammonium salt.
Amines having the following general structural
fnrm~il a
:',
CA 02017126 1999-09-03
R
/NH
R/
are most preferably dialkyl amines in which R is a straight
chain radical having 10 to 30 carbon atoms, more preferably
14 to 24 carbon atoms. Individual examples are dioleyl
amine, dipalmitin amine, di-coconut fatty amine, and
dibehenyl amine and, more preferably ditallow fatty amine.
DESCRIPTION OF PREFERRED EMBODIMENTS
The novel amides and/or ammonium salts of amino-
alkylene polycarboxylic acids having general structural
formulas I and II are added to the petroleum middle
distillate in quantities of from 50 to 1,000 ppm, more
preferably 100 to 500 ppm. Generally, the middle
distillates already contain ethylene vinyl ester
copolymers, especially ethylene vinyl acetate copolymers as
described in, for example, DE 19 14 756.
According to a preferred embodiment, the
petroleum middle distillate compositions contain small
amounts of components of the following additive
combination:
a) 50 to 1,000 ppm, more preferably 100 to 500
ppm of amino-alkylene polycarboxylic acid
derivatives having general structural
formulas I and /or II;
b) conventional ethylene copolymers flow
improves, for example, ethylene vinyl ester
copolymers in quantities of from 50 to
6
-_ 2 0 '1 7 1 2 6
1,000 ppm, more preferably 50 to 500; and
c) conductivity improvers in the form of salts, especially
carboxylic acids and sulfonic acids and/or their metal
salts and ammonium salts in quantities of from 0.25 to
40 ppm, more preferably 1.5 to 20 ppm.
The conventional flow improvers (b) are thoroughly
described in the patent literature. Examples are Federal
Republic of Germany 19 14 756, EP 214786 (a-alefin/MSA-ester)
and EP 155807 (alkyl fumarate/VAC-copolymers). However,
likewise terpolymers are also examples which, along with
ethylene and vinyl esters or acrylic esters contain other
comonomers polymerized in situ.
Preferred copolymers (b) are those comprising
essentially ethylene and from 25 to 45 weight percent of vinyl
acetate, vinyl propionate, or ethylhexyl acrylate. In
addition, there are copolymers which contain, for example,
fumaric acid ester. The molecular weight of the flow improver
generally is from 500 to 5,000, more preferably 1,000 to
3,000.
Typical, too, are mixtures of different flow
improvers.
Conductivity improvers (c) for the middle
distillates are generally hydrocarbon soluble carboxylic acids
and/or sulfonic acids and/or their salts.<
The base conductivity of middle distillates is about
5 to 10 ps/m, measured according to DIN 51 412. Fluctuations
occur by different amounts of water, salts, naphthenic acids,
phenols, and other sulfur and nitrogen containing compounds.
Increasing the conductivity by a factor of from 2
to 3, based on the base conductivity, is sometimes
advantageous for the dispersing behavior of the paraffin
dispersants described.
Adding conductivity improvers as described in, for
example, DE-OS 21 16 556 generates an improvement in the
response behavior even in amounts of from 0.3 to 1 ppm in the
middle distillate. Other less effective conductivity
7
A
201726
improvers require, of course, a higher concentration. Adding
clearly greater amounts than claimed is indeed possible,
however, offers no substantial technical advantage.
Other individual examples are metal salts of
hydrocarbon soluble carboxylic acids and sulfonic acids such
as the commercial designation ASA*3/Shell, as well as other
conventional conductivity improvers, for example, commercially
available Stadis* 450 from DuPont, whose composition is
unknown.
l0 The special effect of the aforesaid combination
a+b+c is surprising and can not be determined from the
properties of the components.
The present invention is more closely illustrated
by the following examples.
A) Preparation of the nitriloacetic acid amides:
1) 240 g (0.48 moles) of ditallow fatty amine and 35
20 g (0.12 moles) of ethylene diamine tetraacetic acid
were melted and heated to 19o°C, whereby the water
of reaction resulting was continuously distilled
of f . The reaction was terminated after about 25
hours, at an acid number less than 5, and at an
amine number less than 1.1. By applying a water
jet vacuum (2 hours at 12o°C), the water of
reaction was completely removed. Obtained was 265
g of a brown, wax like solid (=paraffin dispersing
agent PD (D) in the tables).
30 2) 100 g (0.2 moles) of ditallow fatty amine and 14.6
g (0.05 moles) of ethylene diamine tetra-acetic
acid were heated 8 hours to 180°C. After this time
about 50 percent of the amine reacted into amine
(acid number 45.8; theoretical 49.7). Obtained was
97.6 g of the amide/ammonium salt as a light brown,
* Trade mark
8
2o1~~2s
wax like solid.
3) At 80°C, 28.65 g (0.15 moles) of nitrilotriacetic
acid (Trilon* A) was added to the melt of 229.5 g
(0.45 moles) of ditallow fatty amine.
~mhcPrn~Pnt-_1 v . the
* Trade mark
9
A
CA 02017126 1999-09-03
reaction mixture was heated 10 hours from 180° to
190° C. The product was dried 2 hours at 120°C
using a water jet vacuum to completely remove the
water of the reaction. Obtained was 249 g
(theoretical 250 g) of light brown, wax like
solid (= paraffin dispersing agent PD (H) in the
tables) .
B) Petroleum middle distillate compositions, comprising:
a) nitrilotriacetic acid amides according to A) ;
b) as flow improvers:
FI (A) ethylene/vinyl propionate (with about 40
weight percent vinyl propionate) having an
average molecular weight of about 2,500 (vapor
pressure osmometry).
FI (B) ethylene/vinyl acetate (with about 30
weight percent of vinyl acetate) having an
average molecular weight of about 2,500.
FI (C) ethylene/ethylhexyl acrylate (with about
50 weight percent of ethylhexyl acrylate) having
an average molecular weight of about 2,500.
CA 02017126 1999-09-03
c) As conductivity improvers:
LV (E) (Kerostat 500g) according to Example 1 of
DE 21 16 556.
LV (F) (ASA 3/Shell) a hydrocarbon soluble
sulfocarboxylic acid salt.
LV (G) (Stadis 450/DuPont) a conductivity
improver of unknown composition.
Heating oil EL and diesel fuel having a
commercially available Federal Republic of Germany refinery
quality were used as middle distillates in the following
experiments. They are designated as middle distillates A,B,
and C, whereby DK is the diesel fuel and whereby HEL is
heating oil EL.
Middle
Distillate
DK 1 (A) DK 2 (B)
HEL (C)
Cloud Point (C) - 7C - 7C + 4C
CFPP (C) - 10C - 13C - 1C
Density at 20C(g/ml) 0.817 0.827 0.826
Boiling begins (C) 156 165 171
20~ Boiling Point(C) 204 210 218
11
CA 02017126 1999-09-03
90~ Boiling Point(°C) 309 318 344
Boiling Ends (°C) 350 358 369
Description of the Test Methods
The middle distillates were tested with different
quantities of flow improvers alone and or together with
paraffin dispersing agents in combination with conductivity
improvers at temperatures below the cloud point. Cooling
was done with the help of a temperature program. Middle
distillate A, and B (diesel fuels, Tables I, II) were
cooled at room temperature to -12°C at a cooling rate of
1°C per hour, and stored at -12°C for 24 hours. Middle
distillate C (heating oil, Table III) was also cooled from
about 20°C to -4°C at 1°C per hour and also stored at -
4° C
for 24 hours. The experiments were done with 100 ml and
1,000 ml of middle distillate. Tables I-III show: the
volume of the sedimentated percent
paraffin
phase in
(optically evaluated); the cloud point (CP) and the
cold
filter plugging (CFPP) near the bottom (below 40 vol.
point
percent); CP and CFPP in the upper region (above 60 vol.
percent) as well as the CP and CFPP of the middle
distillate containing the additives before the storage
test.
12
CA 02017126 1999-09-03
As the tables show, the sedimentation of the
paraffins is further reduced by adding conductivity
improving additives.
Table I: Middle distillate A
Table II: Middle distillate B
Table III: Middle distillate C
Table IV-VI: Middle distillate A.
The following abbreviations are found in the tables:
T - Cloudy
K - Clear
LD - Easily dispersing
D - Dispersing
FI - Middle distillate flow improver (b)
PD - Paraffin dispersing agent (a)
LV - Conductivity improver (c)
13
CA 02017126 1999-09-03
v C-~ ~..
O
,L," U ~ ~ ~ ~ ~ N N N M OM M ~ N N
V , , , , , , , , , , , , , , , , ,
~
N ~~ N N N .~ N N O pp ~ O ap pp O pp
r, .-~ ,-, .-~ ,-~ ,-,
, , , , , , , , , , , , , , , , ,
N N O d. ,n ~ ~ M N O O .-~ fT O N 'd' 1~
.~ .-r .-~ .~ N N N N M N N N
, , , , , , , , , , , , , , , , ,
Gs, U
~
~ ~ o ~ 'ch ~n N N d- ~-i N ~' 1~ I~ ~- h IW '1 Iw oo
1-~ ~..i , , , , , , , , , , , , , , , ,
x
H H ~ ~ H ~ ~ c~ A A A ~ A A ~ A A
N 00 I~ T M
PH C/W r ,11 .-~ N M N M M M N O O N O O ~ M O
4~
~~
~'' ~ U V d- oo . o0 o u, o o. o. a. o .o 0o a\
.-a .-~ ~ ~ ~ .-a ~ ~ ~ N ~-~ N N M N N N
, , , , , , , , , , , , , , , , ,
U
0
~ ~ 0 00 00 0o tW o0 0o I oo W o0 0o W oo Iw o0 00
p~ PA ~.. , , , , , , , , , , , , , , , , ,
a
O ~ ~ , , , , , ~ ~ , .--yf1 , ~-W f1 , ~i ~f1
U
~a ~, W W -~L~ ~
H~ , , , , , , a a , a a , a a , a a
m a
a
0
A~U~ ~°n~c~ .r°,~°n,°n~~go°og
, , , ~, M u'1 , , ~ ~ .-a M M M W 1 ~f1 ~f1
., n ~ ~ ~ n ~ ~ n n n n
b
~l ~ A a A ~ A ~ ~ A A A
H , , , ~, ~ ~ , ,
a
O ~ ~ ~ ~ ~ O
M v0 , , , , , .-~ .-, ~ M M M M M M
H
~ ~ n ~ n n n n n ~ n n ~ n n n
~r ~r ~r ~ ~r ~ ~ ~..i ~r ~ ~r ~r
w w w w w w w w w r= w w w w ~ w w
14
CA 02017126 1999-09-03
~ ~, ~.
' o
~r, u, N -d- .c o ~r d- c~ ~t .a oo ,-, o~ o o~ o
.~ .-r N .~ .~ N .-a .-~ .~ .~ .--~ N M N M N M
, , , , , , , , , , , , , , , , ,
~
o
00 00 ov ~ ~ o0 00 o. a\ Iw a' 00 00 o~
, , , , , , , , , , , , , , , , ,
~ N N M N N M ~ N N N ~ ~O O'~ 1~ 00
.~ .-r .-r .r~ N ~-~ N N
o , , , , , , , , , , , , , , , , ,
a ~
a ~ o er ~f- u~ ~m ~o ~t ~,o d- ~O oo ~n 1 0o h o0 00
.... , , , , , , , , , , , , , , , , ,
~x
HHHHHH~~~AAAAAAAA
a
M N ,~~o
A
' ~''.ifWi.M-~ 0~0 4~0~oo~o~N~~N~00000
W a
C4 ~
M M N M ~f1 ~f1 N M eh' 'd' V1 .-i O~ 00 00 O~ 00
.-a .~ N .--~ .~ .-i .-a .-i ~ .-i ~ N N N N N N
U , , , , , , , , , , , , , , , , ,
0
' ~o .~.
C4 ~ ~ o I v o0 00 00 00 1 00 00 00 0o W v o0 00 00 00
V .... , , , , , , , , , , , , , , , , ,
a
, y--I ~f1 , r-1 ~f1 , ~ ~f1 , .--~ 1!1
U~
°' a~ ~" w w w w w w w w
W r yr v ~ v v ~ v
H , , , , , , a a , a a , a a , a a
v
-a a
to~V~ °gg °°°°o~g°o~°o
, , , ~--~ M ~(1 , , .1 .-i e-1 M M M lf1 ~f'1 ~f1
n n n n ~ n n n n ~ n ~
AA~-1 AAA~'1AAA~a
H , , , ~ ~ ~ ,
a
o 00 g o O O $ ~ 0 g o 0
M v0 , , , , , ~ ~ ~ M M M M M M
m H
n n n ~ ~ n n ~ ~ ~ ~ ~
~ ~r ~ ~ ~ a ~r ~r ~ 'r ~r
H F'-' w ~ w , , , , , w w w w w w w w w
CA 02017126 1999-09-03
' o
(y0 yD N ~ oo ~ N v0 Iw oo ~ ~ "'~.., oo .-~-~ .-~~i
, , , , , , , , , , , , , , , , ,
o
M N '~t + ~. er + .+- N .-r M N j- + .-y
, , , , , , , , ,
N M N Iw d- N ~-~ V'
a ~ o
+ + + + + + + + + + + + + + + + +
a
x
P~. ~ E-~ I-~ E-~ C4 ~ t~ M t~ H ~ ~ H A A H A A
a
v
o ~" ~ o
t v ~ M O N O O 00 O O M 00 O~ O u'1
~ t~ ~ ~ N N O~ W t- oo O~ .-~ u1 W ~ i ~ N N r, O
G4
v ~e~'U .-.
U ~ ~ " ''' ~-r ~ ''-' ~I ~ o~ 0 0 0 ~ ~ ~ ~ o
V , , , , , , , , , , , , , ,
0
w
'd' M er M 'd- M ~f 'd- et M eh eh 'cY '~ 'vt '~t '~
V pa ~ ~ + + + + + + + + + + + + + + + + +
a
n n ~ ~ ~ , ',-~ tf1 , .-a ~!1 W nf1 , e-1 tn
v
°' a~ ~ w w w w w w w w
H , , , , , , a a , a a , a a , a a
W v
~rl b
0 0 0 0 0 0 0 0 0 0 0 0
u1 O O u1 ~n u'1 O O O O O O
, , ~ .-~ M ~f1 , , ~r-~ .-~ .-1 M M M ~f1 vf1 ~f1
Ar n ~ ~ n n n n n n ~
b q vv ~ E L ~ ~ L L L L ~ ~ ~
tA fA l~ ~ ~ ~ A A A A A A
F-~ , , , ~ r-~ ~ , ,
a
O O O O O O O O O O O
o ~ ~ ~ ~ ~ ~ ~ 0 0 0 0 ~ o
H
w ~ ~ .... .., ~ ~ ,., .-.. ..-. ,~. .-. .-. ...
d ~ d ~ d ~ <C ~ d
v ~ ~ ~ ~r ~ ~ ~ ~r ~.r .~r ~
F-' w w w , , , , , w w w ~' w ~ w w w
16
CA 02017126 1999-09-03
~ ~" o
.~I,i U .~-v M N N M M N N
, , , , , , , ,
~
O
~, ~ 1~ ~ 1~ M I~
, , , , , , , ,
°' ~' ~~. .-a tw .o o d- ~ o M
N N CV M N N N N
~.s~., U ~~
b
a ~
N d- M tw N 1~ ~ 1~
w..i , , , , , , , ,
~ ~ ~ A ~ A ~ A
,
o ~ o o N o 00 0
u~''U
V ~ ~ °J oo a\ Iw N ~D ~o M ~n
() N N N M CV N N CV
U
o ~ ~
op,U
i w
~ V o 00 0o Iw oo Iw tw Iw o0
, , , , , , , ,
a
, , N N , , N N
U~
.r., , ,
a a , , a a
H
01 a
~ei
q o
U~ g ~ °o
,
b
CA A A A
H , ~ , ~ , ~ ,
~0 0 0 0 0
.l V G7~
w w
°' ~ ~ ~ ~ U U U U
H ~'~ w w w w w w w w
17
CA 02017126 1999-09-03
~ o
~-~ M N N
n
0
~, 00 00 00
, ,
() .N-as N N N
o , , , ,
p., U v
a U
a
a
~ ~ A A
0
V p,, ~ ~ ~ 0 0 0
0
0
,~ a
~ ~ ~ o
N N N
V w
U ~ ~ o ~ 00 00 ly o0
0
a
, , .-mn
U
a~
H~ , , a a
a
.r.,
cg ~ , g g
A A
A ~ A
b
0 0 8 0 0
M M M M
r-1 ~LI ~ ~" ~ ~ ~ n
w w w w
18
CA 02017126 1999-09-03
.-.
0
N ~ N M
~ i ~ i
N
~ ~ U ,-, ~-, ,-, ..-,
() N N N ~ ~ N
p., U v
U
O~ M M I~ M M
H H A H H A
U
o
o '~ ~ o
i Rr cn ~ ~ ~N-~ o °~-~° ~
G4
U
V ono ~ .oo~o~oo
~ i i N n i i
0
O ~
W ~ ~ o 0o tw o0 00 0o Iw
V
A
.W f1 ~f1 M
U~
a~
va' ~ ~ ~ ~ c~ c~
a a a ,.~.a a a
.r.,
v
~.a b
0
~U ~ o
~n ~ mn
b A a ~ ~
'b
H ~ ~ A ~ ~ A
a
0 0
V~ o o ~ S
a
w
F-' w w w w w w
19
