Note: Descriptions are shown in the official language in which they were submitted.
H 0517 PCT 2 1 4 7 2 ~ ~
13.7.1993
A process for the simplified purification of useful
materials an~ mixturQs of useful materials from the
field of wetting agents, detergents ~nd/or clqaning
products and associated useful materi~ls
Field of the Invention
This invention relates to a simplified process
for improving the purity and, in particular, the color
and odor quality of useful materials and mixtures of
useful materials from the field of wetting agents,
detergents and/or cleaning products and to associated
useful materials, for example from the textile treatment
field. The invention seeks in particular to provide a
simplified method of substantially improving the odor
and/or color of the useful materials or mixtures of
useful materials in question without having to resort to
the expensive purification processes hitherto applied.
However, the concept of purification in accordance with
the invention is not confined to such sensorially
perceivable impurities, instead other unwanted impuri-
ties from the production and/or processing of usefulmaterials or mixtures of useful materials of the type
mentioned can be taken up by the purification process
according to the invention and separated from the
material to be ultimately obtained.
Prior Art
The problems addressed by the present invention
are discussed in the following with reference to useful
materials from the field of laundry detergents, but is
2147~ l
H 517 PCT 2
by no means limited to this field.
It is general knowledge that laundry detergents
or components used in laundry detergents have to meet
relatively stringent purity requirements. Particular
significance is attributed in this regard to the odor;
and color requirements which the detergent or detergent
mixture is expected to satisfy, as sensorially perceived
by the end user. The detergent marketed, for example,
as a free-flowing solid material should be light and
best pure white in color. A brown or grey product
creates the impression of inferior quality and dirti-
ness. The odor of the useful material or mixture of
useful materials is almost more important. A musty,
tallow-like odor results in instinctive rejection. This
aspect of product production is complicated by the fact
that auxiliaries of the type in question here often have
to be stored for long periods in tightly sealed con-
tainers under variable external conditions and, when the
pack is opened by the consumer, the odor of its contents
ZO is perceived very sensitively by the consumer. Musty,
tallow-like, rancid or other strong odor impressions
result in instinctive rejection although it is only in
rare cases that any deterioration in the product proper-
ties can be objectively determined.
In addition, experts concerned with the produc-
tion of useful materials or mixtures of useful materials
of the type targeted by the invention are confronted by
further problems of purity which, in the same way as the
factors mentioned above, involve considerable expense
for the purification of the useful materials or mixtures
thereof. The problems involved in the complete removal
of alkylene oxide residues (EO and/or PO) and dioxane
from the useful materials obtained by alkoxylation, for
example nonionic or anionic useful materials, are
discussed purely by way of example in the following.
H 517 PCT ~147 2 ~ 7
A complicating factor in this regard is that key
useful materials from the field with which the invention
is concerned are either based on natural materials or
are obtained by synthesis from petroleum-based raw
materials. Surfactants are produced by multistage;
processes which, although providing optimal results in
regard to the desired component in the particular
process stage, also lead to the formation of unwanted
impurities, optionally in trace amounts. This is
illustrated by way of example in the following with
reference to certain anionic surfactant components and
certain nonionic surfactant components:
Components based on natural materials of the type
in question here generally contain fatty alcohols or
fatty alcohol mixtures of natural origin as an oleo-
philic component. These fatty alcohols are in turn
obtained by reduction of the carboxylic acids obtained
from natural oils and fats. These intermediate fatty
alcohols are then provided with hydrophilic functional
elements. In the case of anionic surfactants for
example, a sulfonation and/or sulfation reaction is
carried out, generally using S03 or chlorosulfonic acid.
To produce nonionic surfactant components based on fatty
alcohols, water-soluble residues are introduced by
alkoxylation or by reaction with water-soluble glycose
residues. All the reactions take place under demanding
process conditions, particularly elevated temperatures.
In general, the starting materials of natural origin are
not individual compounds, but rather mixtures such as
are provided by nature and such as can be obtained from
such mixtures by simple separation processes.
It is known that stringent requirements in regard
to the purity of the starting materials, the inter-
mediate reaction products and the required end products
arise out of these preconditions. The cost of useful
H 5~ a ~ 4
materials of the type in question and mixtures thereof
is determined to a large extent by the technical effort
involved in the particular purification stage.
Useful materials and mixtures of useful materials
for use in wetting agents, detergents and/or cleaning;
products may be present either as liquid components or
in the form of pourable granules. They are generally
obtained by drying intermediately obtained aqueous
preparations of this class of compounds. For decades,
preparations such as these have been universally spray-
dried on an industrial scale. Hot air or mixtures of
air and hot combustion gases are used as the drying gas
stream.
Applicants have worked extensively on the pos-
sibility of applying the principle of drying with
superheated steam to useful materials and mixtures
thereof for use in wetting agents, detergents and/or
cleaning products. It has surprisingly been found that
the advantages of drying with superheated steam, partic-
ularly in regard to ecology and energy, may also be used
for the present basically very sensitive field of
application or product field. Thus, DE-A 40 30 688
describes a process for recovering fine-particle, solid
or free-flowing useful materials or mixtures thereof for
wetting agents, detergents and/or cleaning products from
water-containing preparations thereof using superheated
steam as the drying hot gas stream. In this process,
drying of the particulate material is terminated before
it is endangered by heat.
Particular emho~;ments of and improvements in
such drying processes using superheated steam as the hot
gas stream and their application to useful materials and
mixtures thereof for wetting agents, detergents and/or
cleaning products are disclosed in a number of other
earlier applications in applicants' name, cf. in par-
2147207
H 517 PCT 5
ticular earlier German patent applications DE-P 42 04
035.3, DE-P 42 04 090.6, DE-P 42 06 050.8, DE-P 42 06
521.6, DE-P 42 06 495.3, DE-P 42 08 773.2 and DE-P 42 09
432.1.
A particularly important further development is;
concerned with the unexpected advantageous product
properties exhibited by a solid pourable and free-
flowing starting material obtained by drying with
superheated steam. A description is given as to how a
microporous structure can be developed and fixed in a
starting material initially obtained by drying with
superheated steam and - building on this - as to how
mixtures of useful materials from the field in question
can be formulated in a hitherto unknown manner, cf.
applicants' earlier German patent application P 42 34
376.3.
The teaching according to the invention described
hereinafter for the production of useful materials of
the type mentioned above and mixtures thereof with
greater purity for distinctly less effort builds on the
experience and working principles according to the
above-cited DE-A 40 30 688 and the earlier applications
mentioned. Accordingly, the disclosure of that document
and the earlier applications in question are hereby
specifically included as part of the disclosure of the
present invention which is to be understood in combina-
tion with the further observations and working prin-
ciples described in the following.
The teaching according to the invention is based
on the surprising observation that the treatment of a
starting material as disclosed in the description of the
present invention not only leads to drying under the
conditions of the treatment with superheated steam, the
method used for this treatment may also be used with
particular advantage for removing unwanted constituents
21~7~
H 517 PCT 6
from the useful materials and mixtures thereof. Thus,
it is possible to remove relatively small or even
relatively large quantities of foreign substances from
the starting material to be purified by a comparatively
S brief treatment in accordance with the invention. ~ot~
only can olfactorily troublesome components, for ex-
ample, be removed from the starting material, the
teaching according to the invention also includes -
where necessary - a simultaneous bleaching treatment of
the starting mixture in its technical actions. These
possibilities provide for a simplified purification
process for the production of high-quality useful
materials and mixtures thereof by which the purity
requirements can be satisfied more easily and, hence,
less expensively.
Doscription of tho Invention
In a first embodiment, therefore, the present
invention relates to a process for improving the purity
and, in particular, the color and odor quality of useful
materials and mixtures of useful materials from the
field of wetting agents, detergents and/or cleaning
products or related useful materials (hereinafter refer-
red to as the "starting material"), characterized inthat an impurity-containing starting material is treated
with superheated steam under the conditions described in
detail hereinafter. According to the invention, bleach-
ing agents are used in the starting material to obtain
improvements in color. In one important embodiment of
the process according to the invention, the impurity-
containing starting material is e~c~^~ to the treatment
with superheated steam in fine-particle form and, in
particular, under normal pressure. Preferably, water-
containing mixtures of the starting material to be
2147~07
H 517 PCT 7
purified are subjected to the treatment with superheatedsteam. At the same time, drying may be carried out in
the superheated steam atmosphere.
In one embodiment, therefore, the teaching
according to the invention relates to the use of the;
process for the drying of water-containing preparations
of useful materials and/or mixtures of useful materials
from the field defined in accordance with the invention
in a spray drying zone and/or in a fluidized bed using
superheated steam as the drying gas for the simultaneous
purification of a starting material containing in
particular steam-volatile impurities.
In important embodiments, the invention thus
makes use of the fact that a large number of unwanted
impurities such as are encountered in the field in
question show comparatively high volatility, particular-
ly in a steam-filled atmosphere, by comparison with the
final components to be ultimately obtained in the useful
material or mixture of useful materials. This not only
applies to low molecular weight, but difficult-to-remove
residues, such as ethylene oxide and/or propylene oxide
and also dioxane, from corresponding reaction mixtures,
unwanted impurities of relatively high molecular weight,
such as unreacted fatty alcohols or fatty alcohol mix-
tures or partial oxidation products derived therefrom,more particularly lower carbonyl cu~ounds, such as
fatty aldehydes, can also be effectively removed in an
inert steam atmosphere from mixtures with the desired
pure materials or pure mixtures of the starting materi-
al.
Purification stages in the production of usefulmaterials of the type in question and mixtures thereof
using steam are known per se. The support provided by
the use of steam in the removal of troublesome impuri-
ties in relatively large or relatively small quantities
2 1 4~ 7
H 517 PCT 8
is also known. For example, the removal of unreactedfatty alcohol in the production of nonionic surfactant
components from the class of alkyl polyglycosides (APG)
is described in EP-B 0 092 876 (Procter & Gamble). In
general terms, however, the purification of useful;
materials or mixtures thereof based on natural substan-
ces by so-called steaming is another known method of
removing above all troublesome trace substances from the
material to be purified (cf. EP-B 0 283 862, Henkel).
The invention goes beyond these known proposals.
The starting material to be purified is treated under
the effect of superheated steam which was described for
the first time in DE-A 40 30 688 as a drying gas for
useful materials and mixtures of useful materials of the
type in question. The drying process disclosed in DE-A
40 30 688 may be used in the context of the teaching
according to the invention, although the teaching
according to the invention goes beyond this. The
invention now makes it possible for the first time to
subject an impurity-containing starting material to such
a drying process and, at the same time, to obtain the
highly purified end products required. It is clear that
the multistage production of useful materials of the
type targeted by the invention can be considerably
simplified in this way. Depending on the particular
circumstances, substantial savings can be made in the
intermediate purification of precursors or end products
before they are finally dried to form the desired end
product. Accordingly, compared with conventional spray
drying and/or fluidized bed drying with a hot gas phase
based on air and combustible gases, the invention
provides new ways of obtaining high-quality useful
materials and useful material mixtures of the type in
question.
The teaching according to the invention is of
21472U7
H 517 PCT 9
particular importance in connection with the production
of useful materials which are free from unwanted odor
emissions. Irrespective of this or at the same time,
however, the teaching according to the invention also
enables the color of the end products to be improved to;
the extent that they are either light of white in color.
The removal of the olfactorily troublesome
foreign components is the immediate result of the treat-
ment of the material in the superheated steam phase. In
the preferred embodiment of the invention, water-con-
taining mixtures of starting materials are introduced in
finely divided form into a zone through which super-
heated steam is passed. The following reaction sequence
then occurs: the drop of water-containing liquid gener-
ally introduced at temperatures below the evaporationtemperature of the water under the working conditions
results in the immediate condensation of more water on
the drop of liquid. At the same time, the heat of
condensation passes over to the droplet-like material.
This dilution process continues until the temperature of
the material introduced corresponds to the evaporation
temperature of the water under the working conditions.
In general, therefore, this temperature is of the order
of lOO C. When the evaporation temperature is reached
in the drop, the drop as a whole is dried in the one-
component water/steam system without the formation of
the rigid outer shell formed in the conventional drying
process. This drying process is described in detail in
earlier German patent application P 42 34 376.3, to
which reference is again expressly made. The outcome of
this drying process in superheated steam is the highly
porous inner structure - described in the earlier
application - of the dry material which is solid at the
drying temperature. This highly porous structure is
utilized in the teaching according to the invention.
~14.?~7
H 517 PCT 10
The basically volatile and, in particular, steam-
volatile impurities are not trapped in the drop and
prevented from evaporating, instead they are capable of
passing into the gas phase during the drying process or
even thereafter under the effect of the superhea~ed;
steam and are discharged with the superheated steam.
The purified material remains behind. A corresponding
simplification of the removal of foreign components is
guaranteed in the treatment of liquid components in the
superheated steam phase.
The possibility of removing foreign components
discussed herein mainly affects the removal of unwanted
odor-emitting components and the removal of comparative-
ly light volatile or steam-volatile components of
neutral odor. The teaching of the invention goes beyond
this insofar as colored impurities from a corresponding-
ly contaminated starting material can be removed at the
same time. To this end, the teaching according to the
invention is characterized by the use of bleaches in the
starting material. Suitable bleaches are both oxidative
and reducing bleaches known per se. Typical examples of
oxidative bleaches are hydrogen peroxide, persalts, such
as percarbonates, perborates, persulfates, hypochlorite
salts, more particularly alkali metal hypochlorite, and
the like. So-called bleach activators known from the
field of washing and textile auxiliaries and described
in detail hereinafter may be used together with the
oxidative bleaching agents, as known per se.
Examples of reducing bleaching components are, in
particular, compounds of this class which do not lead to
unwanted secondary reactions in the presence of the
superheated steam. Examples of such compounds are
phosphorus compounds, more particularly hypophosphorous
acid and its salts, more particularly alkali metal
and/or alkaline earth metal salts.
21~7207
H 517 PCT 11
Bleaches may be added to the starting mixtures to
be purified in the particular quantity required.
Normally, quantities of up to about 10% by weight are
sufficient, even for comparatively serious contamina-
tion, quantities of from about 0.5 to 5% by weight;preferably being added to the starting material to be
bleached (percentages by weight based on the particular
component to be bleached or rather the corresponding
multicomponent mixture).
The need for bleaching and/or the need for
additional lightening will make corresponding measures
of the teaching according to the invention desirable
when individual components are more or less heavily
discolored - normally above all to brown from individual
synthesis steps - and/or when the multicomponent mixture
as a whole, for example a laundry detergent or a corre-
sponding tower powder for the production of laundry
detergents, is to be additionally lightened in color.
Corresponding discolorations of individual components
are known problem factors in the sulfonation and/or
sulfation of oleophilic components in the production of
surface-active compounds of the anionic surfactant type.
Comparatively speaking, however, corresponding color
problems can also arise in the production of surface-
active components containing quaternary ammonium groupsas used, for example, in fabric softeners for the treat-
ment of laundry after washing. Another known example of
the occurrence of unwanted brown discoloration is to be
found in the class of APG compounds used as nonionic
surfactants. The glucose content in particular of this
class of compounds leads to unacceptable brown dis-
coloration on account of its temperature sensitivity.
The teaching according to the invention is particularly
helpful here in enabling color to be lightened. The
critical temperature range beyond which browning norm-
4~ r~
H 517 PCT 12
ally occurs in the APG-containing material can be
reliably avoided by correspondingly controlling the
temperature of the superheated steam phase. At the same
time, the preferred form of working up according to the
invention via a fine-particle starting material in the;
gas phase of the superheated steam ensures that no
caking and hence no local overheating in the APG-con-
taining material can occur on metal surfaces. Another
known example of problematical discoloration in surfac-
tan's is to be found in anionic surfactants based on ~-
s-~ ~ituted ester sulfonates, more particularly the
corresponding methyl ester sulfonate salts (MES), and
the disalts of the alpha-sulfofatty acids derived
therefrom by ester saponification.
In one particular embodiment of the invention,
the starting material to be purified is treated with a
superheated steam phase to which traces of ozone have
been added. This addition of ozone can be important in
particular in connection with improvement of the olfac-
tory property spectrum of the starting material to be
treated. Even very small amounts of ozone in the
superheated steam can lead to a perceptible improvement
in the odor of the material. According to the inven-
tion, the ozone is preferably added in quantities in the
lower ppm range, based on the particular quantity of
vapor removed from the drying circuit of the superheated
steam which corresponds to the water evaporated during
the process and introduced with the starting material to
be purified. The quantity of ozone added preferably
amounts to no more than about 1 ppm and, in particular,
is less than 0.5 ppm. In a particularly preferred
embodiment, the ozone is added in a quantity of from
about 0.05 to 0.2 ppm. The basis for these ppm figures
is the same as mentioned above. The ozone may be added
to the circulating steam, preferably immediately before
H 517 PCT 13 2147207
the superheated steam is returned to the drying zone,
and/or directly to the drying zone.
In one preferred embodiment, the treatment
according to the invention is applied to an impurity-
containing starting material which is capable of with-;
standing an at least brief increase in temperature to
the evaporation temperature of the water under the
process conditions, more particularly to temperatures in
the range from about 90 to llO C, with virtually no
damage. Although liquid and/or solid starting materials
are equally suitable for this purpose, particularly good
results can often be obtained with materials which, in
their dried state, are present as solids at temperatures
of 90 to llO-C and which, as the starting material to be
purified, are unsatisfactory above all in odor and/or
color.
In another preferred embodiment, flowable and
sprayable aqueous solutions, emulsions and/or suspen-
sions of the impure starting material are subjected to
the treatment with the superheated steam. In this
embodiment, at least partial drying of the water-con-
taining flowable materials can be combined with the
treatment according to the invention in the spray drying
zone and/or in the fluidized bed.
In other respects, the parameters for the treat-
ment of the starting material with superheated steam
correspond to the disclosure of DE-A 40 30 688 and
applicants' earlier applications cited in this connec-
tion. Particulars of the composition of suitable useful
materials and mixtures of useful materials for wetting
agents, detergents and/or cleaning products can be found
in particular in earlier German patent application P 42
34 376.3. This document describes useful materials or
mixtures of useful materials of the type in question
which are solid at temperatures in the range from 100 to
H 517 PCT 14
llO-C and preferably at temperatures in the range up to
about 120-C and of which the plasticity and surface
tackiness are limited to such an extent that there is no
significant adhesion of the particles to one another
and/or within their open-pored inner structure, even;
under the conditions of exposure to the superheated
steam. In important embodiments, the teaching according
to the invention makes use of these elements of the
teaching of the earlier application. Both individual
useful materials and also carrier beads of mixtures of
useful materials as defined in the earlier application
and, finally, the useful materials used to impregnate
these carrier beads may be, or may already have been,
subjected to purification in accordance with the teach-
ing of the invention.
The purification process according to the inven-
tion is carried out at normal pressure or at only
slightly increased or only slightly reduced pressures.
Thus, preferred deviations from normal pressure in
either direction are pressure deviations of up to about
0.15 ~ar, preferably no more than about 0.1 bar and,
more preferably, no more than 0.01 to 0.05 bar. The
application of slightly increased internal pressures of
the system rules out any unwanted penetration of oxygen-
containing ambient air and, hence, unwanted secondary
reactions with the useful material to be treated, even
where damaged areas are present. The superheated steam
is normally used at temperatures in the range from 100
to 450 C and preferably at temperatures in the range
from about 115 to 350 C. Further particulars in this
regard can be $ound in applicants' above-cited patents
and patent applications relating to the field in ques-
tion. The closed circuits required for the use of
superheated steam afford a significant advantage so far
as the treatment according to the invention is con-
2 1 4 7 2 0 ~
H 517 PCT 15
cerned. The stream or partial stream of superheated
steam laden with the impurities discharged is not let
off into the atmosphere as such, but instead is sub-
jected to condensation. Most of the impurities dis-
charged pass into the liquid and/or solid phase during
this condensation step. Residues remaining in the gas
phase may be suitably worked up, for example by burning,
together with the gas phase separated from this subse-
quent condensation step. Depending on their quality,
the discharged quantities of former starting materials
of the material to be purified, which accumulate during
the condensation of the vapor stream removed from the
circuit, may be destroyed without causing any damage or
returned to suitable preliminary stages of the produc-
tion of the particular useful materials. It is possible
in this way to purify the particular starting materials
completely safely, without any environmental damage and
with optimum economy, even when hitherto typical costly
steps, particularly in the form of distillation-based
purification and the like, have not been carried out
with the hitherto usual intensity, if at all, in the
production of the material to be purified.
Without any claim to completeness, further
observations on useful materials and auxiliaries from
the specialist field in question are presented in the
following, again with specific reference to the general
knowledge of the expert.
al) Suitable anionic surfactants of sulfate or
sulfonate structure are, for example, alkyl
benzenesulfonates, alkane sulfonates, olefin
sulfonates, alkyl ether sulfonates, glycerol
ether sulfonates, ~-methyl ester sulfonates,
sulfofatty acids, alkyl sulfates, fatty alcohol
ether sulfates, glycerol ether sulfates, hydroxy
2147~7
H 517 PCT 16
mixed ether sulfates, monoglyceride (ether)sul-
fates, fatty acid amide (ether)sulfates, sulfo-
succinates, sulfosuccinamates, sulfotriglycer-
ides, isethionates, taurides and alkyl oligo-
glucoside sulfates. If the anionic surfactants;
contain polyglycol ether chains, they may have a
conventional homolog distribution, although they
preferably have a narrow-range homolog distribu-
tion.
a2) Suitable anionic surfactants of carboxylate
structure are, for example, soaps of natural or
synthetic, preferably saturated fatty acids.
Soap mixtures derived from natural fatty acids,
for example coconut oil fatty acid, palm kernel
oil fatty acid or tallow fatty acid, are particu-
larly suitable. Soap mixtures of which 50 to
100% consist of saturated C121g fatty acid soaps
and 0 to 50% of oleic acid soaps are preferred.
Amide soaps, ether carboxylic acid salts and
sarcosinates are also suitable.
a3) In the context of the present invention, "anionic
surfactants of sulfate, sulfonate and/or carboxy-
late structure" are also understood to include
amphoteric or zwitterionic surfactants which
contain at least one of these groups in the
molecule. Typical examples are alkyl betaines,
alkyl amidobetaines, aminopropionates, aminogly-
cinates, imidazolinium betaines and sulfobeta-
nes .
The anionic surfactants may be present in
the form of their sodium, potassium and ammonium
salts and also in the form of soluble salts of
organic bases, such as mono-, di- or triethanol-
2147~07
H 517 PCT 17
amine. The substances mentioned are all known
compounds. Particulars of their structure and
production can be found in relevant synoptic
works, cf. for example J. Falbe (ed.), "Surfac-
tants in Consumer Productsn, Springer Verlag,;
Berlin, 1987, pages 54 to 124 or J. Falbe (ed.),
"Ratalysatoren, Tenside und Mineraloladditive",
Thieme Verlag, Stuttgart, 1978, pages 123 to 217.
10 b) Nonionic surfactant compounds in the context of
the teaching according to the invention may
perform various functions as useful materials.
on the one hand, they are washing-active com-
ponents which cooperate synergistically with the
anionic surfactants in the usual way. On the
other hand, however, greater significance can
also be attributed to the class of nonionic
surfactants, for example in the form of disper-
sants, structure breakers and the like.
Nonionic surfactant compounds may be liquid
or solid at room temperature, as known per se.
With reference to general specialist knowledge,
the following nonionic surfactant compounds are
mentioned by way of example:
bl) The liquid alcohol ethoxylates used as nonionic
surfactants are derived, for example, from
primary alcohols preferably containing 9 to 18
carbon atoms and, on average, 1 to 12 mol ethy-
lene oxide in which the alcohol radical may be
linear or branched, more particularly methyl-
branched in the 2-position, or may contain mix-
tures of linear and methyl-branched radicals such
as are typically present in oxoalcohol radicals.
However, linear radicals of alcohols of native
?, ~. 4~
H 517 PCT 18
origin containing 12 to 18 carbon atoms, for
example of coconut oil fatty alcohol, tallow
fatty alcohol or oleyl alcohol, are particularly
preferred.
Cl2~ alcohols containing 3 EO or 4 EO, ~
alcohols containing 7 EO, Cl3l5 alcohols con-
taining 3 EO, 5 EO, 7 EO or 8 EO, Cl2l8 alcohols
containing 3 EO, 5 EO or 7 EO and mixtures
thereof, such as mixtures of Cl2l4 alcohol con-
taining 3 EO and Cl2l8 alcohol containing 5 EO,
can be particularly preferred.
The degrees of ethoxylation mentioned are
statistical mean values which, for a special
product, may be a whole number or a broken
number. Preferred alcohol ethoxylates have a
narrow-range homolog distribution (narrow-range
ethoxylates, NRE). Alcohol ethoxylates contain-
ing on average 2 to 8 ethylene oxide groups are
particularly preferred.
b2) Other suitable nonionic surfactants are alkyl
oligoglycosides corresponding to general formula
(I):
Rl-O-[G~
in which Rl is a primary linear or 2-methyl-
branched aliphatic radical containing 8 to 22 and
preferably 12 to 18 carbon atoms and G stands for
a glycose unit containing 5 or 6 carbon atoms,
preferably glucose. The degree of oligomeriza-
tion x, which indicates the distribution of mono-
glycosides and oligoglycosides, is a number of 1
to 10 and, for example, lies in the range from
about 1.2 to 4 and, more particularly, 1.2 to 2.
2147207
H 517 PCT 19
b3) Nonionic surfactants of the amine oxide type, for
example N-coconut oil alkyl-N,N-dimethyl amine
oxide and N-tallow alkyl-N,N-dihydroxyethyl amine
oxide, and of the fatty acid alkanolamide type
may also be suitable. The quantity in which;
these nonionic surfactants are present is prefer-
ably no more than that of the ethoxylated fatty
alcohols and, in particular, no more than half
that quantity.
b4) Other suitable surfactants are polyhydroxyfatty
acid amides corresponding to formula (II):
R2CO-N-(Z) (II)
in which R2CO is an aliphatic acyl radical
containing 6 to 22 carbon atoms, R3 is hydrogen,
an alkyl or hydroxyalkyl radical containing 1 to
4 carbon atoms and (Z) is a linear or branched
polyhydroxyalkyl radical containing 3 to 10
carbon atoms and 3 to 10 hydroxyl groups. The
polyhydroxyfatty acid amides are known substances
which may normally be obtained by reductive
amination of a reducing sugar with ammonia, an
alkyl amine or an alkanolamine and subsequent
acylation with a fatty acid, a fatty acid alkyl
ester or a fatty acid chloride. Processes for
their production are described in US 1,985,424,
2,016,962 and 2,703,798 and in International
patent application WO 92/06984 (Procter &
Gamble). The polyhydroxyfatty acid amides are
preferably derived from reducing sugars contain-
ing 5 or 6 carbon atoms, more particularly from
4~2Ql
H 5~7 PCT 20
glucose. Accordingly, the preferred polyhydroxy-
fatty acid amides are fatty acid-N-alkyl gluca-
mides corresponding to formula (III):
R3 OH OH OH
l l
R2CO-N-CH2-CH-CH-CH-CH-CH2OH (III)
I
OH
Preferred polyhydroxyfatty acid amides are fatty
acid-N-alkyl glucamides corresponding to formula
(III), in which R3 is hydrogen or an amine group
and R2CO is the acyl radical of caproic acid,
caprylic acid, capric acid, lauric acid, myristic
acid, palmitic acid, palmitoleic acid, stearic
acid, isostearic acid, oleic acid, elaidic acid,
petroselic acid, linoleic acid, linolenic acid,
arachic acid, gadoleic acid, behenic acid or
erucic acid or technical mixtures thereof. Fatty
acid-N-alkyl glucamides (III) obtained by reduc-
tive amination of glucose with methyl amine and
subsequent acylation with lauric acid or C~
coconut oil fatty acid or a corresponding deriva-
2S tive are particularly preferred.
c) Suitable organic and inorganic builders which may
be used in mixtures of useful materials to be
purified in accordance with the invention are
soluble and/or insoluble components showing a
mildly acid, neutral or alkaline reaction which
are capable of precipitating or complexing
calcium ions.
35 cl) Suitable and, in particular, ecologically safe
2147207
H 517 PCT 21
builders, such as finely crystalline synthetic
water-containing zeolites of the NaA type, which
have a calcium binding power of 100 to 200 mg
CaO/g (as determined in accordance with DE-A 24
12 837), are preferably used. Their average;
particle size is normally in the range from 1 to
10 ~m (as measured with a Coulter Counter, volume
distribution). Suitable substitutes or partial
substitutes for phosphates and zeolites are
crystalline, layer-form sodium silicates corre-
sponding to general formula (IV):
NaMSi~O2~1 Y H2O (IV)
in which M is sodium or hydrogen, x is a number
of 1.9 to 4 and y is a number of 0 to 20, prefer-
red values for x being 2, 3 or 4. Crystalline
layer silicates such as these are described, for
example, in European patent application EP-A 0
164 514. Preferred crystalline layer silicates
(IV) are those in which M is sodium and x has a
value of 2 or 3. Beta- and delta-sodium disili-
cates corresponding to formula (V):
Na2Si2O5 Y H2O (V)
are particularly preferred, beta-sodium disili-
cate being obtainable, for example, by the
process described in German patent application
DE-A 39 39 919.
c2) Other suitable builder components, which may be
used in particular together with the zeolites,
are layer compounds of the hydrotalcite type and
(co)polymeric polycarboxylates, such as polyacry-
21~1Z~7
H 517 PCT 22
lates, polymethacrylates and, in particular,
copolymers of acrylic acid with maleic acid,
preferably those of 50% to 10% maleic acid. The
relative molecular weight of the homopolymers is
generally in the range from 1,000 to 100,~00
while the relative molecular weight of the
copolymers is generally in the range from 2,000
to 200,000 and preferably in the range from
50,000 to 120,000, based on free acid. A par-
ticularly preferred acrylic acid/maleic acid
copolymer has a relative molecular weight of
50,000 to 100,000. Suitable, but less preferred
compounds of this class are copolymers of acrylic
acid or methacrylic acid with vinyl ethers, such
lS as vinyl methyl ethers, in which the acid makes
up at least 50%. Other suitable compounds of
this class are polyacetal carboxylic acids, for
example of the type described in US 4,144,226 and
US 4,146,495, and also polymeric acids which are
obtained by polymerization of acrolein and subse-
quent disproportionation with alkalis and which
are made up of acrylic acid units and vinyl
alcohol units or acrolein units.
25 c3) Other suitable organic builders are the polycar-
boxylic acids preferably used in the form of
their sodium salts, such as citric acid, ethylene
diamine tetraacetic acid (EDTA) and nitrilotri-
acetic acid (NTA), providing their use is not
ecologically objectionable.
c4) Other suitable ingredients of the wetting agents,
detergents and/or cleaning products are water-
soluble inorganic alkalizing agents, such as
bicarbonates, carbonates or silicates; alkali
21~72~7
H 517 PCT 23
metal carbonate and alkali metal silicate, above
all sodium silicate with a molar ratio of Na20 to
SiO2 of 1:1 to 1:4.0, are particularly suitable.
5 d) The other detergent ingredients include redeposi-;
tion inhibitors (soil suspending agents), foam
regulators, bleach activators, optical brighten-
ers, fabric softeners, dyes and fragrances and
also neutral salts. Other important detergent
ingredients are, for example, bleaches and
enzymes. The extent to which these components
need the purification treatment according to the
invention will have to be determined from case to
case. In the formulation of useful materials or
mixtures of useful materials for the field of
application according to the invention, these
components are added last - usually separately -
to the mixtures of useful materials used. An
exception may be the bleach activators which, as
mentioned above, may also be used in the mixtures
of useful materials as auxiliaries for improved
bleaching under the conditions according to the
invention during the actual treatment with
superheated steam. Nevertheless, the subsequent
introduction of additional quantities of bleach
activators may also be advisable in such a case
for a mixture of useful materials, for example in
the form of a laundry detergent.
30 dl) Examples of bleach activators, which are intended
to lead to an improved bleaching effect at
washing temperatures of 60 C and lower, are N-
acyl or O-acyl compounds which form organic
peracids with H202, preferably N,N'-tetraacylated
diamines, such as N,N,N',N'-tetraacetyl ethylene
214~ 20rl
H 517 PCT 24
diamine, and also carboxylic anhydrides and
esters of polyols, such as glucose pentaacetate.
d2) The function of redeposition inhibitors is to
keep the soil detached from the fibers suspended;
in the liquor and thus to prevent discoloration.
Suitable redeposition inhibitors are water-
soluble, generally organic colloids, such as for
example the water-soluble salts of polymeric
carboxylic acids, glue, gelatine, salts of ether
carboxylic acids or ether sulfonic acids of
starch or cellulose or salts of acidic sulfuric
acid esters of cellulose or starch. Water-
soluble polyamides containing acidic groups are
also suitable for this purpose. Soluble starch
preparations and other starch products than those
mentioned above, for example degraded starch,
aldehyde starches etc., may also be used. The
same applies to polyvinyl pyrrolidone (PVP).
d3) Suitable foam regulators are combinations of
suitable surfactants. A reduction can also be
obtained by additions of non-surface-active
organic compounds. In many cases, reduced
foaming, which is desirable for washing machines,
is achieved by combining various types of surfac-
tants, for example sulfates and/or sulfonates
with nonionic surfactants and/or with soaps. In
the case of soaps, the foam-inhibiting effect
increases with the degree of saturation and the
carbon chain length of the fatty acid component.
Accordingly, suitable foam-inhibiting soaps are
soaps of natural and synthetic origin which have
a high percentage content of Cl82~ fatty acids.
3S Suitable non-surface-active foam inhibitors are
2I ~ 72~ ~
H 517 PCT 25
organopolysiloxanes and mixtures thereof with
microfine, optionally silanized silica, paraf-
fins, waxes, microcrystalline waxes and mixtures
thereof with silanized silica. Bisacylamides
derived from C12-20 alkyl amines and C2-6 dicar-;
boxylic acids may also be used. Mixtures of
various foam regulators, for example mixtures of
silicones and paraffins or waxes, may also be
used with advantage. The foam regulators or
inhibitors are preferably adsorbed to a granular
carrier substance soluble or dispersible in
water.
d4) Suitable optical brighteners are derivatives of
diaminostilbene disulfonic acid or alkali metal
salts thereof, for example salts of 4,4'-bis-(2-
anilino-4-morpholino-1,3,5-triazin-6-ylamino)-
stilbene-2,2'-disulfonic acid or compounds of
similar structure in which the morpholino group
is replaced by a diethanolamino group, a methyl-
amino group, an anilino group or a 2-methoxy-
ethylamino group. Brighteners of the substituted
4,4'-distyryl diphenyl type, for example the com-
pound 4,4'-bis-(4-chloro-3-sulfostyryl)-diphenyl,
may also be present. Mixtures of the brighteners
mentioned above may also be used.
d5) Further improvements in whiteness can be obtained
in known manner if, in addition to the usual
optical brighteners, the detergents also contain
small quantities of a blue dye. A particularly
preferred dye is Tinolux (a product of Ciba-
Geigy).
35 e) In order to improve the rapid dissolution of
~4~lQ~l
H 517 PCT 26
basically poorly soluble components, for example
corresponding anionic surfactants, such as FAS,
even at room temperature or only moderately
elevated temperatures, it can be important to use
so-called structure breakers which, in many;
cases, are extremely effective in only very small
quantities, based on anionic surfactant. Even
the purification of such structure breakers as
these by the process according to the invention
can lead to important improvements.
el) Suitable structure breakers may be selected from
a number of both solid and liquid substances
which are hydrophilic, soluble in water or dis-
persible in water. Suitable structure breakers
are, for example, lower polyalkylene glycols
which are derived from linear or branched glycols
containing 2 to 6 carbon atoms, preferably
polyethylene glycol or polypropylene glycol, and
which have a relative molecular weight of 200 to
12,000. Particularly preferred structure break-
ers are polyethylene glycols having a relative
molecular weight of 200 to 4,000, liquid poly-
ethylene glycols having a relative molecular
weight of up to 2,000 and, more particularly, in
the range from 200 to 600 showing particularly
advantageous properties.
e2) The sulfates and, in particular, disulfates of
lower polyalkylene glycols, more particularly
polyethylene glycol and 1,2-propylene glycol, are
also suitable. Sulfates and/or disulfates de-
rived from polyethylene glycols and polypropylene
glycols having a relative molecular weight of 600
to 6,000 and, more particularly, in the range
214 7~ 0 7
H 517 PCT 27
from 1,000 to 4,000 are particularly preferred.
The disulfates generally originate from polygly-
col ethers which can be formed in the alkoxyla-
tion of alcoholic components through the presence
of traces of water.
e3) Another group of suitable structure breakers
consists of the water-soluble salts of monosuc-
cinates and/or disulfosuccinates of lower poly-
alkylene glycols. Of particular significance in
this regard are the corresponding polyethylene
glycol and polypropylene glycol compounds,
sulfosuccinates and disulfosuccinates of polygly-
col ethers having a relative molecular weight in
the range from 600 to 6,000 and, more particular-
ly, in the range from 1,000 to 4,000 being
particularly preferred.
Salts and preferably alkali metal salts,
more particularly sodium and potassium salts, and
also ammonium salts and/or salts of organic
amines, for example triethanolamine, are suitable
for the use of the anionically modified polyalky-
lene glycols as structure breakers. The most
important salts for practical application are the
sodium salts of the sulfates, disulfates, sulfo-
succinates and disulfosuccinates of polyethylene
glycol and polypropylene glycol.
Mixtures of the polyalkylene glycols and
their anionically modified derivatives in any
ratio are also preferably used. A mixture of
polyalkylene glycol and the sulfosuccinates
and/or disulfosuccinates of the polyalkylene
glycols is particularly preferred. However, a
mixture of polyalkylene glycol and the corre-
sponding sulfates and/or disulfates and a mixture
O~
H 517 PCT 28
of polyalkylene glycol and the corresponding
sulfates and/or disulfates and also the corre-
sponding sulfosuccinates and/or sulfodisuccinates
are also suitable.
e4) Other suitable structure breakers preferably used
in accordance with the invention are the adducts
of approx. 20 to approx. 80 mol ethylene oxide
with 1 mol of an aliphatic alcohol essentially
containing 8 to 20 carbon atoms which are well
known ingredients of detergents and cleaning
products. Of particular importance are the
adducts of 20 to 60 mol and, more particularly,
25 to 45 mol ethylene oxide with primary alco-
hols, such as for example coconut oil fatty
alcohol or tallow fatty alcohol, with oleyl
alcohol, with oxoalcohols or with secondary
alcohols containing 8 to 18 and preferably 12 to
18 carbon atoms. Examples of particularly
preferred structure breakers from the group of
highly ethoxylated alcohols are tallow fatty
alcohol containing 30 EO and tallow fatty alcohol
containing 40 EO. It is also preferred to use
mixtures containing highly ethoxylated alcohols,
for example mixtures of tallow fatty alcohol
containing 40 EO and water or mixtures of tallow
fatty alcohol containing 40 EO and polyethylene
glycol having a relative molecular weight of 200
to 2,000.
e5) Other suitable structure breakers are ethoxy-
lated, vicinal internal alkanediols or 1,2-
alkanediols with a carbon chain containing 8 to
18 carbon atoms and 4 to 15 mol ethylene oxide
per mol diol. Only one of the two OH groups or
21472~
H 517 PCT 29
both OH groups of the alkanediol can be ethoxy-
lated.
e6) Other suitable structure breakers are modified
nonionic surfactants terminated by an acid group.
The nonionic surfactants in question are nonionic
surfactants, more particularly fatty alcohols, in
which one OH group has been converted into a
group containing a carboxyl group. Accordingly,
nonionic surfactants terminated by an acid group
include esters or partial esters of a nonionic
surfactant with a polycarboxylic acid or a
polycarboxylic anhydride. Examples of acid-
terminated nonionic surfactants are the known
polyether carboxylic acids and esters or semi-
esters of C~l~ alcohols with succinic anhydride,
maleic anhydride, maleic acid or citric acid.
e7) Another group of suitable structure breakers
consists of alkylene glycol monoalkyl ethers
corresponding to general formula (VI):
R40(CH2CH2o)nH (VI)
in which R4 is a radical containing 2 to 6 carbon
atoms and n is a number of 1 to 8. Examples of
this group of additives are ethylene glycol
monoethyl ether and diethylene glycol monobutyl
ether.
f) Important components for the starting mixtures or
rather useful materials according to the inven-
tion are so-called cationic active substances
from the field of wetting agents, detergents and
cleaning products or the associated auxiliaries.
2~47~7
H 517 PCT 30
Of particular importance in this regard are the
quaternary ammonium compounds which are widely
used, for example, as fabric-softening components
and which contain at least one and preferably two
relatively long-chain alkyl radicals at a quater--
nary nitrogen atom.
So-called esterquats which show relatively
high ecological compatibility and which - start-
ing from a trialkanolamine, typically triethanol-
amine - contain relatively long-chain fatty acid
components bound in ester form are now of par-
ticular importance in this regard. Mixtures of
mono-, di- and triesters are normally present,
the monoester content being, for example, from 15
to 25 mol-%, the diester content from 40 to 50%
and the triester content making up the remainder
(for relevant literature, see for example EP-A
239 910 or DE-A 19 35 493). Esterquats according
to these and other literature references (for
example EP-A 0 293 953 and EP-A 0 309 052) are
reaction products of triethanolamine or ethoxy-
lated monoethanolamine with mixtures of saturated
and unsaturated C6z8 fatty acids. The reaction
product initially formed is subsequently quater-
nized with dimethyl sulfate. Further particulars
of the class of compounds in question can be
found in DE-A 37 10 064 (EP-A 0 284 036) and in
EP-A 0 295 385.
The following Examples are intended to illustrate
the invention without limiting it in any way.
2 1 ~ 7 h 0 7
H 517 PCT 31
~r~ples
~mple 1
In an experimental pilot-plant spray drying tower
of the "minor production" type manufactured by Niro-;
Atomizer, a slurry of the sodium salt of a Cl6/l8 fatty
alcohol sulfate was converted by addition of sodium
carbonate into a free-flowing surfactant powder. The
mixing ratio between the anionic surfactant and sodium
carbonate was 4:1, based on dry matter.
The aqueous slurry of the fatty alcohol sulfate
used is a white to pale yellow firm paste having the
following characteristic data:
Washing-active substance (Epton): 54 - 58%
Fatty alcohol sulfate: 53 - 55%
Unsulfonated: 1 - 3%
NaCl content: 1%
Na2S0, content: 2%
pH value (3% aqueous preparation): 10 - 11.5
After the aqueous soda solution had been added,
the slurry had a dry matter content of 47.7% by weight.
The slurry is sprayed through a two-component nozzle
(propellent gas nitrogen) and dried in countercurrent
with superheated steam. The following operating para-
meters were established for drying with superheated
steam:
Steam entry temperature: 250 C
Steam exit temperature: 175 - 180-C
Reduced pressure in tower: 16 mbar
Feed pump pressure: 5.5 bar
Feed temperature: 80 C
Feed input: 12 kg/h
2~
H 517 PCT 32
Steam input: 350 m3/h
Propellent gas for the
two-component nozzle
quantity: 3.3 m3/h
pressure: 0.2 bar
The product obtained had a dry matter content of
99.2% by weight and an apparent density of 293 g/l. 90%
solubility in water at 20-C was achieved after 40
seconds. The whiteness of the dried product reaches a
value of 77.6 at a wavelength of 460 nm. A bleaching
agent was then added to the slurry described above. The
operating parameters for drying with superheated steam
are identical with those mentioned above. The following
product qualities were obtained by addition of various
quantities of sodium hypochlorite as bleaching agent:
Composition NaOCl Apparent Solubil- White-
based density ity (90%) ness
on DM (460 nm
(%) (g/l) mins./s without W)
80% Sulfopon T55 0 293 -/40 77.6
20% Soda
80% Sulfopon T55 0.5 226 -/41 80.1
20% Soda
80% Sulfopon T55 1 230 -/37 80.3
20% Soda
"Sulfopon T55" is a commercial name used by
applicants for an anionic surfactant based on fatty
alcohol sulfate.
For comparison, a commercial laundry detergent
(applicants' nPersil TASn) has a whiteness of 79.7 at a
2147207
H 517 PCT 33
wavelength of 460 nm. Covering the entire wavelength
range by support with W light is irrelevant in the case
of the anionic surfactant powders mentioned above
because no optical brighteners are used.
Ex~mple 2
The procedure was as described in Example 1. A
slurry containing 24.1% solids was dried in the super-
heated steam phase. The solid components of the start-
ing mixture were the sodium salt of a Cl6~l8 fatty alcohol
sulfate ("Sulfopon T55") mentioned in Example 1, the
disodium salt of a Cl6~l8 alpha-sulfofatty acid and sodium
carbonate in a mixing ratio of 4:1:1. The dried powder
had an apparent density of 220 g/l and a solubility
(90%) of 20 seconds.
The disodium salt of the C16l1B alpha-sulfofatty
acid is a pale brownish paste having the following
characteristic data:
Washing-active substances (Epton): 26.3 %
Unsulfonated fatty acid: 2.09%
Degree of sulfonation: 89.6%
NaCl content: 2.2%
Na2S0~ content: 3.1 %
The following Table shows the product properties
of the superheated-steam-dried powders with different
additions of bleach to the starting slurry:
2l4~Q~
H 517 PCT 34
T~bls 2: Test results
Composition NaOCl Apparent Solubil- White-
based density ity (90%) ness
on DM (460 nm;;
(%) (g/l) mins./s without UV)
Sulfopon T55 0 220 -/20 48.6
+ soda + disalt
(4:1:1)
Sulfopon T55 1 249 -/35 64.9
+ soda + disalt
(4:1:1)
Sulfopon T55 2 248 -/32 67.1
+ soda + disalt
(4:1:1)
Sulfopon T55 4 253 -/16 76.0
+ soda + disalt
(4:1:1)
EY~mple 3
The slurry of the anionic surfactant based on
fatty alcohol sulfate with added soda mentioned in
Example 1 has a tallow-like musty odor which is regarded
as unpleasant. Emission of the odor intensifies,
particularly when the paste is heated. After drying
with superheated steam as described in Example 1, the
powder-form product is odorless. After the fine par-
ticles have been fixed by any form of granulation, there
is no irritation of the mucous membrane.
2I~72~7
H 517 PCT 35
EY~mple 4
In its paste-like initial state, the surfactant
mixture of Example 2 (sodium salt of a Cl6~l8 fatty
alcohol sulfate and disodium salt of a Cl6/l~ alpha-
sulfofatty acid) has a tallow-like musty odor which is;
regarded as being highly obtrusive and unpleasant, above
all in the relatively warm state (T -40 C) and in the
event of prolonged storage. The product dried with
superheated steam is a storable powder of neutral odor
which is accepted without reservation.
