Note: Descriptions are shown in the official language in which they were submitted.
21747 3
WO 95/11210 PCT/EP94/03348
A process for the production of fatty alcohols based on
vegetable fats and oils by fractionation
~3ackground of the Invention
This invention relates to a process for. the produc-
tion of fatty alcohols based on vegetable fats and oils
with an iodine value in the range from 20 to 110, to
fatty alcohols based on vegetable fats and oils with an
iodine value of 20 to less than 95 and to the use of
these products for the production surface-active formula-
tions.
Statement of Related Art
Fatty compounds, particularly unsaturated fatty
alcohols, are important intermediates for a large number
of products of the chemical industry, for example for the
production of surfactants and skin-care products. An
overview of these intermediate products is provided, for
example, by U. Ploog et al. in Seifen-ole Fette-Wachse
109, 225 (1983). They are produced fram more or less
unsaturated fatty acid methyl esters which may be hydro-
genated, for example, in the presence of chromium- or
zinc-containing mixed catalysts [Ullmann~s Enzyclopaedie
der technischen Chemie, Verlag Chemie, Weinheim, 4th
Edition, Vol. 11, pages 436 et seq.].
The prior art in this field is an industrial process
using animal fats and oils which has also been carried
out by applicants and in which the unsaturated fatty
alcohols accumulating after hydrogenation are distilled
at a bottom temperature of, for example, X120 to 2.50 ° C and
under a reduced pressure of 1 to 20 mbar, as measured at
217473
WO 95/11210 2 PCT/EP94/03348
the head of the column. Since the production of unsat-
urated fatty alcohols involves high costs, the distilla-
tion conditions were designed to minimize the loss of raw
materials. In fact, a yield of around 90% of the theore-
tical (and hence a loss of 10~) was achieved in this way.
Unfortunately, the products had a distinct odor. Another
disadvantage was that the fatty alcohols of the prior art
show unsatisfactory storage and low-temperature behavior.
Unsaturated fatty alcohols with iodine values of 20
to 95 are particularly preferred for' applicational
reasons because they have a particularly favorable
solidification point for use in cosmetic products.
Hitherto, unsaturated fatty alcohols with iodine values
in the range mentioned have always been based on animal
fats. The desired iodine value range is established by
blending various products with different iodine value
ranges. The iodine value range cannot be established by
distillation-based processes because the iodine value or
rather the iodine value range of fatty alcohols or fatty
acids based on animal fats remains substantially constant
during fractionation.
However, animal fats have the disadvantage that they
are extremely heterogeneous. For example, animal fats
contain nitrogen-containing compounds, such as amides or
steroids, such as cholesterol for example, which are
directly or indirectly responsible for the unpleasant
odor of the products mentioned above. The nitrogen-
containing compounds can enter into secondary reactions
which adversely affects product stability, particularly
oxidation stability, and leads to discolared products.
There is an urgent need in the cosmetic market in
particular for purer raw materials of higher quality - a
requirement which normally can only be satisfied by
increasingly more expensive technical processes and
additional purification steps. In the case of unsatura-
' CA 02174723 2005-08-25
3
ted fatty alcohols, there is a need above all for prod-
ucts with improved color and odor quality and more
favorable low-temperature behavior. Added to this is the
fact that, in recent years, consumer behavior has changed
to the extent that consumers now attribute considerable
importance to purely vegetable products.
Known vegetable fatty alcohols have iodine values
below 20 or very high iodine values above 100. Fatty
alcohols with iodine values in the applicationally
l0 preferred range of 20 to 95 mentioned above are not
known. The blending of fatty alcohols with very dif-
ferent iodine values does not lead to satisfactory
products.
The problem addressed by the present invention was
to provide fatty alcohols based on vegetable fats and
oils which would have iodine values in the applicational
ly preferred range and which, at the same time, would
have greater oxidation stability than unsaturated fatty
alcohols based on animal fats and equivalent or better
low-temperature behavior.
Description of the Invention
The present invention relates to a process for the
production of a fatty alcohol, based on vegetable fats and
oils, of the general formula (I):
R10H (I)
where R1 is a saturated or unsaturated, linear or branched
group, which is a constituent group of the vegetable fats
and oils, having from 8 to 22 carbon atoms comprising the
steps of: hydrogenating a fatty acid, a fatty acid methyl
ester or a combination thereof to form a fatty alcohol; and
removing a head fraction from said fatty acid, said fatty
acid methyl ester and said fatty alcohol in such a quantity
that said fatty alcohol has an iodine value of from 20 to
110 and less than about 4.5% by weight of conjugated
compounds.
CA 02174723 2005-08-25
4
Surprisingly, it has been found that, in contrast to
products based on animal fats, it is possible to produce
fatty alcohols based on vegetable fats and oils with
iodine values in the range mentioned above which contain
substantially unsaturated fatty alcohols and mixtures of
saturated and unsaturated fatty alcohols corresponding to
general formula (I), the iodine value being adjustable to
the desired range by simple fractionation in accordance
with applicational requirements. The products based on
vegetable fats and oils obtained by the process according
to the invention show better oxidation stability and less
odor than corresponding products based on animal fats.
The present invention also relates to fatty alcohols
of the general formula I
R10H ( I )
wherein R' is a saturated or unsaturated, linear or
branched group which is a constituent group of vegetable
fats and oils, having from 8 to 22 carbon atoms produced by
a process comprising the steps of . hydrogenating a fatty
acid, a fatty acid methyl ester or a combination thereof to
form a fatty alcohol; and removing a head fraction from said
fatty acid, said fatty acid methyl ester and said fatty
alcohol in such a quantity that said fatty alcohol has an
iodine value of from 20 to 110 and less than 4.5°s by weight
of conjugated compounds.
i i ., i ~~ ii a i."v"i"i,
CA 02174723 2005-O1-12
In addition, compounds corresponding to formula (I), in
which R1 is a group containing l2 to 20 carbon atoms, are
preferred. Preferably, the iodine value is between 40 and
85.
The fatty alcohols according to the invention show
5 particularly high stability when only a low percentage of
conjugated compounds is present. The fatty alcohols
according to the invention based on vegetable fats and
oils preferably have a content of conjugated compounds
below 6% by weight and, more preferably, below 4.5% by
weight.
Unsaturated or partLly unsaturated vegetable fats and
oils are used as starting materials for the process
according to the invention. Palm oil, palm stearin oil,
palm kernel olefin oil, coconut oil, palm kernel oil,
sunflower oil, new rapeseed oil, soybean oil, peanut oil,
rapeseed oil, linseed oil and olive oil are particularly
.preferred. The fats consisting essentially of triglycer
ides are converted into the fatty acids in known manner
by pressure hydrolysis and optionally esterified with
methanol or are transesterified with methanol to the
fatty acid methyl ester. The fatty acid or the fatty
acid methyl ester is then hydrogenated to the correspond-
ing fatty alcohol by known methods. The percentage
content of saturated and unsaturated constituents and the
chain length distribution are determined by the vegetable
oils used. In the above compounds corresponding to
formula (I), R1 is a group containing 8 to 22
- ~ carbon atoms and preferably 12 to 2r0 carbon atoms.
Through the use of vegetable fats and oils as
starting products, the fatty acids/fatty acid methyl
esters used or the hydrogenation product are mixtures of
fatty acids, fatty acid methyl esters or fatty alcohols
differing in their chain lengths. According to the
invention, the iodine value of the fatty alcohols to be
produced is adjusted by fractionating the fatty acids
c
WO 95/11210 6 PCT/EP94/03348
obtained by pressure hydrolysis, the fatty acid methyl
esters obtained by transesterification of the triglycer-
ides or the hydrogenation product obtained by hydrogena-
tion of the fatty acid or the fatty acid methyl ester.
The iodine value of the product to be fractionated is
determined before fractionation. Depending on the
starting product or its iodine value and the desired
iodine value, a certain quantity of head fraction is
removed during fractionation. 8y removing the head
fraction, the iodine value of the fatty alcohol is
increased. To adjust the iodine value of the product,
the iodine value of the product which has not yet dis-
tilled over is monitored during fractionation. For
example, it is possible by the process according to the
invention to obtain from coconut oil/palm kernel oil a
fatty acid or fatty acid methyl ester fraction which
contains fatty acid or fatty acid methyl ester with chain
lengths of 16 to 18 carbon atoms, so-ca:Lled Clsila fatty
acid or fatty acid methyl ester, as its principal consti-
tuent. The required chain length distribution can also
be adjusted by corresponding fractionation of the fatty
alcohol.
The fractionation conditions under reduced pressure
for the unsaturated fatty alcohols obtained, for example,
from the hydrogenation stage have long been known.
Fractionation may be carried out in batches~or continu-
ously under reduced pressure. Superheated steam, for
example, may be used for heating, the bottom temperature
being in the range from 220 to 250°C for example.
:30 The actual fractionation process takes place in a
packed column with fittings characterized by a low
pressure loss. Suitable fittings are, for example,
ordered metal packs. Further examples can be found in
ROMPP Chemie Lexikon, Thieme Verlag, Stuttgart, 9th
Edition, Vol. 3, page 2305 (1990) under the keyword
~1747~~
WO 95/11210 7 PCT/EP94/03348
"column fittings" and in the literature cited therein.
The necessary fine vacuum of 1 to 20 mbar at the
head of the column can be obtained, fox example, with
water ring pumps and preceding steam jet pumps. The
pressure drop throughout the distillation plant should
preferably be no more than 20 mbar.
An improvement in the end product can be obtained by
distilling the unsaturated fatty alcohols in such a way
that a residue of up to 10% by weight and preferably from
2 to 7% by weight is obtained. The color value and odor
of the end products are distinctly further improved by
this measure.
Industrial Applications
:L 5
The unsaturated fatty alcohols based on vegetable
fats and oils obtainable by the process according to the
invention are substantially colorless and odorless and
show particularly favorable low-temperature behavior.
Accordingly, they are suitable as raw materials for the
production of laundry detergents, dishwashing detergents
and cleaning products and also hair-care and body-care
products, in which they may be present in quantities of
1 to 50% by weight and preferably 5 to 30% by weight,
based on the particular product.
The invention is illustrated by the following
Examples:
Exaa~p 1 a s
:30
Fatty acid methyl esters were hydrogenated in a
typical hydrogenation reactor under a pressure of around
225 bar and at a temperature of 275 to 33U°C in the pres-
ence of a CuCr04 catalyst. The hydrogenation product is
distilled, a corresponding head fraction being removed.
2174723
WO 95/11210 8 PCT/EP94/03348
Example 1
A Cl2ila palm kernel oil methyl ester obtained from
the transesterification of palm kernel oil and subsequent
fractionation was fractionated to a Clziia and Clsila methyl
ester. The Clsiia methyl ester was hydrogenated to the
fatty alcohol as described above. The crude product was
distilled in a two-stage vacuum fractionating unit, a
head fraction of 3% by weight being removed and a residue
of 3% by weight remaining.
A fatty alcohol (FA) with the following chain
distribution and the following characteristic data was
obtained:
FA C 12 0.2% by weight
FA C 14 4.5% by weight
FA C 15 0.3% by weight
FA C 16 25.1% by weight
FA C 16' 0.4% by weight
FA C 17 0.3% by weight
FA C 18 8.9% by weight
FA C 18' 52.5% by weight
FA C 18 " 2.9% by weight
FA C 18 " conj. 3.2% by weight
FA C 18 " ' 0.1% by weight
FA C 20 0.6% by weight
Acid value - 0.02
Saponification value - 0.35
OH value - 213.5
Iodine value - 61.3
HZO content - 0.02
Softening point - 26.6C
Hydrocarbon content - 0.87% by
weight
CO value - 360
Hazen - < 10
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WO 95/11210 9 PCT/EP94/03348
Example 2
The product obtained from the hydrogenation in
Example 1 is distilled in such a way that a head fraction
of around 18% by weight is removed, a fatty alcohol with
a relatively high iodine value of 75 being obtained.
This fatty alcohol has the following chain distribu-
tion and the following characteristic data:
FA C 12 0.0% byweight
FA C 14 0.1% byweight
FA C 15 0.1% byweight
FA C 16 12.1% byweight
FA C 16' 0.2% byweight
FA C 17 0.3% byweight
FA C 18 11.5% byweight
FA C 18' 66.5% byweight
FA C 18 " 3.7% byweight
FA C 18 " conj. 4.3% byweight
FA C 18 " ' 0.2% byweight
FA C 20 0.4% byweight
Acid value - 0.02
Saponification value - 0.40
OH value - 210. 5
Iodine value - 75
HZO content - 0.02
Softening point - 23.2 C
Hydrocarbon content - 0.13 %
by
weight
CO value - 306
Hazen - 5
Example 3
Starting out from a mixture of a Clsiis Palm kernel
oil methyl ester (70% by weight) and rapeseed oil methyl
ester (30% by weight) prepared from new rapeseed oil, a
2~ 74 723
WO 95/11210 10 PCT/EP94/03348
fatty alcohol with the following chain distribution and
the following characteristic data was prepared as de-
scribed in Example 1:
FA C 12 0.0% by weight
FA C 14 0.0% by weight
FA C 15 0.2% by weight
FA C 16 23.1% by weight
FA C 16' 0.8% by weight
FA C 17 0.4% by weight
FA C 18 6.4% by weight
FA C 18' 60.3% by weight
FA C 18 " 4.6% by weight
FA C 18 " conj. 3.2% by weight
FA C 18 " ' 0.1% by weight
FA C 20 0,6% by weight
Acid value - 0.02
Saponification value - 0.35
OH value - 213
Iodine value - 73.9
HZO content - 0.03
Softening point - 22.9C
Hydrocarbon content - 0.2% by
weight
CO value - 279
Hazen - < 10
