Process for preparation of alkylglycosides

A process for preparing alkylglycosides by reacting an 8 to 20 carbon atom monohydric alcohol with a monosaccharide in the presence of an acid catalyst, while under partial vacuum, followed by neutralizing the reactant product with an alkaline metal hydroxide in an amount about equal on a molar basis to the amount of catalyst, and removal of the residual unreacted alcohol.

BACKGROUND OF THE INVENTION 
The present invention relates to a process for making alkylglycosides. In 
particular, it relates to a process for making a light straw colored, 
i.e., substantially colorless, alkylglycoside product. 
Alkylglycosides are nonionic surfactants which provide detergency, foaming, 
emulsifying, and wetting properties comparable to those of other nonionic 
surfactants. For a number of years it has been proposed to use 
alkylglycosides as surfactants either alone or in combination with other 
anionic or nonionic surfactants in detergent formulations. 
Despite the long recognized potential uses for alkylglycosides in 
detergents, they have been primarily relegated to use in industrial 
detergency applications. The reason for this is that presently available 
economical processes for making alkylglycosides produce a product having a 
substantial amount of color producing impurities, resulting in a dark, 
coffee-colored product. 
Although the color of the alkylglycoside product may be of little 
importance in some industrial detergent applications, color is crucial for 
many other industrial applications and, as a practical matter, for all 
household detergent applications. The reason for this is simply that, as a 
general rule, those using such products do not wish to wash their clothes 
and dishes with a coffee-colored detergent product. 
To enable the use of alkylglycosides in household detergent formulations, 
there has been a need for a simple and economical process for making a 
substantially colorless, e.g., a light straw colored, alkylglycoside 
product. The present invention provides for such a process. 
SUMMARY OF THE INVENTION 
The present invention provides for a process for making a substantially 
colorless alkylglycoside product which includes the steps of: 
(1) admixing a compound selected from the group consisting of 
monosaccharides, and compounds hydrolyzable to monosaccharides, with a 
monohydric alcohol containing 8 to 20 carbon atoms; 
(2) reducing the pressure to a pressure sufficient to remove a substantial 
amount of any more volatile reaction by-products resulting from the 
reaction between the alcohol and the monosaccharide; 
(3) heating the resulting alcohol, monosaccharide mixture to a temperature 
sufficient to enable them to react to produce an alkylglycoside; 
(4) adding a sufficient amount of an acid catalyst, capable of subsequently 
being completely neutralized with stoichiometric amounts of an alkaline 
substance such that the mixture will not have excessive acidity or 
alkalinity, to effect reaction between the alcohol and the monosaccharide 
to produce an alkylglycoside; and 
(5) adding a sufficient amount of an alkaline substance to neutralize the 
catalyst. 
The process preferably includes the step of removing substantially all of 
the unreacted alcohol. 
DETAILED DESCRIPTION OF SPECIFIC EMBODIMENTS 
In the process of the present invention, the monohydric alcohols having 
from 8 to 20 carbon atoms may be primary or secondary alcohols, straight 
or branch chained, saturated or unsaturated, alkyl or aralkyl alcohols, 
ether alcohols, cyclic alcohols, or heterocyclic alcohols. A preferred 
group of monohydric alcohols are those having the formula ROH where R is 
an alkyl group having from 8 to 16 carbon atoms. 
The monosaccharides of the present invention are the hexoses and pentoses. 
Typical examples include glucose (dextrose), mannose, galactose, talose, 
allose, altrose, idose, arabinose, xylose, lyxose, ribose, and the like. 
Other examples include the monohydrate forms of these compounds. The 
preferred monosaccharide is glucose monohydrate due to its availability 
and low cost. Compounds hydrolyzable to monosaccharides may also be 
employed, such as starch, maltose, sucrose, lactose, melibiose, raffinose, 
methyl glucosides, butyl glucosides, anhydro sugars such as levoglucosan, 
1,6- anhydroglucofuranose, and the like. 
The molar ratio of high molecular weight alcohol to monosaccharide is 
suitably between about 1.5 to about 10, and preferably between about 2.5 
to about 6.0. 
The particular molar ratio chosen depends upon the desired average degree 
of polymerization (DP) of the monosaccharide onto the alcohol. The DP 
represents the average number of monosaccharide derived moieties that are 
attached to each alkyl chain of the alkylglycosides produced. Generally, 
as the alcohol to monosaccharide ratio is increased, the DP decreases. 
Likewise, as this ratio is decreased, the DP increases. Mathematically 
where f equals 5 for glucose and is the number of hydroxyls on the sugar 
ring in the cyclic acetal form, empirically R varies between about 1.5 
-2.5 and is the glucose binding reactivity of the fatty alcohol relative 
to the average reactivity of available non-anomeric hydroxyl groups of the 
sugar moiety and F.sub.T is the mole ratio of alcohol to available 
carbohydrate. 
Preferably, the ratio of alcohol to monosaccharide will be chosen to allow 
the production of an alkylglycoside product having a DP between about 1.2 
and 2.2. 
Low alcohol to monosaccharide ratios, i.e., ratios less than about 1.5, 
should be avoided for optimized reaction control. This is because under 
these conditions two irreversible and undesirable side reactions may take 
place. For example, when glucose is used as the monosaccharide, elevated 
levels of glucose polymers (polydextrose) may form, especially during the 
latter stages of the reaction. This results in excessive foaming and in 
the loss of glucose in the reaction material, actually causing an increase 
in F.sub.T (the alcohol to glucose ratio) and hence a decrease in DP. The 
second reaction involves the dehydration of glucose into hydroxy methyl 
furfural (HMF) and related condensation products (e.g., polyanhydro HMF). 
These substances are, or later yield, color bodies which would contaminate 
the product, preventing the further process steps of the present process 
from producing a substantially colorless alkylglycoside product. 
With glucose as the carbohydrate, the temperature for carrying out the 
reaction may vary between about 85.degree. C. and about 120.degree. C., 
preferably between about 95.degree. C. and about 110.degree. C. If a 
temperature significantly greater than 120.degree. C. is used, the side 
reactions increase faster than the primary reaction. When glucose is used, 
this causes an increase in polydextrose formation and unwanted color 
bodies. 
The temperature also should not be significantly below 85.degree. C. This 
is because such a reduced temperature would cause an unacceptable 
reduction in reaction rate. 
The reaction must take place in an environment which facilitates the 
removal of more volatile reaction byproducts. This environment may be 
conveniently maintained by reducing the pressure under which the reaction 
occurs. This reduction of pressure enables any more volatile reaction 
by-products to be evaporated from the reaction mixture. Preferably, such a 
reduction in pressure is achieved by applying a vacuum to the reaction 
system. 
Preferred apparatus for applying vacuum to the reaction system includes 
steam jets or mechanical vacuum pumps. With higher fatty alcohols the 
final vacuum preferably should be applied at a pressure between about 20 
mm Hg and about 100 mm Hg. This is especially desirable when water is a 
reaction by-product. If the absolute pressure is allowed to exceed 100 mm 
Hg to a significant extent, the water produced in the reaction between the 
alcohol and the monosaccharide may not be removed to the extent required 
to prevent the buildup of a separate water phase in the reaction system, 
which could cause the production of unacceptable amounts of polydextrose, 
when glucose is used as the monosaccharide, or retard the reaction due to 
its reversible nature. 
If the pressure is kept significantly below 20 mm Hg, codistillation of 
lower alcohols may result. In addition, almost all of the water remaining 
in the reaction system could be evaporated. Under these circumstances, 
saccharide moieties, such as glucose, degrade faster, and their 
degradation products more rapidly form unacceptable levels of color 
bodies. An additional problem with vacuums below 30 mm is the inability to 
economically condense water vapor and the associated problems of high 
volumes of non-condensed vapors or contamination of vacuum pump fluids. 
The acid catalyst employed in the present invention is used in an amount 
between about 0.05% and about 5, preferably between about 0.5% and about 
2.0%, based upon the amount of monosaccharide used, on a molar basis. As 
with temperature, the catalyst concentration must be controlled to 
minimize the formation of color bodies and polydextrose when glucose is 
the chosen monosaccharide. 
It is critical that a catalyst that may be easily neutralized with an 
alkaline substance, after the monosaccharide/alcohol reaction has 
terminated, be used to effect termination of the reaction of the present 
process. Otherwise, the resulting isolated product could include an 
unacceptable amount of color bodies, preventing the production of a 
substantially colorless alkylglycoside product. An aliphatic or aromatic, 
mono-sulfonic acid catalyst, for example, a toluene sulfonic acid 
catalyst, has been found suitable for the process of the present 
invention. Other commercially available catalysts like methane sulfonic 
acid, benzene sulfonic acid or lower alkyl substituted sulfonic acids like 
xylene or cumene sulfonic acids may also be suitable. 
To neutralize the catalyst, an alkaline substance, preferably an alkali 
metal hydroxide such as sodium hydroxide, is used in an amount about 
equal, on a stoichiometric basis, to the amount of material needed to 
neutralize the catalyst. If a toluene sulfonic acid catalyst is used, one 
mole of the alkaline substance may, for example, react with one mole of 
catalyst. If one mole of the alkaline substance reacts with one mole of 
the catalyst, for example when sodium hydroxide is used to neutralize the 
catalyst, then an amount of the alkaline material about equal to the 
amount of catalyst, on a molar basis, is used to neutralize the catalyst. 
Such a neutralization reaction would yield one mole of neutral sodium 
toluene sulfonate for each mole of catalyst and alkaline substance used. 
It should be appreciated that when other acid catalysts are used --such as 
sulfuric acid --they may not be easily neutralized. The inability to 
determine and control neutrality with such a catalyst could cause the 
production of an alkylglycoside product having an unacceptable color for 
household detergent uses. 
For example, sulfuric acid forms esters with the alcohol, the 
alkylglycosides and the saccharides present. These esters themselves may 
cause the production of color bodies. Just as important, because the 
amount of these esters may be variable and difficult to determine, it may 
be nearly impossible to calculate the amount of alkaline material needed 
to neutralize the sulfuric acid and its half acid esters present and to 
maintain neutrality during a subsequent isolation step. 
If too much alkaline material is used --such as when stoichiometric amounts 
of a basic compound are applied to a sulfuric acid catalyzed product 
--then the excess alkalinity could cause monosaccharide degradation, 
forming base catalyzed and promoted reactions and volatile and 
non-volatile color bodies. Similarly, if insufficient alkaline material is 
added, then acid catalyzed side reactions may cause the production of 
color bodies during handling and/or undesired polymerization of the 
resulting product during isolation. 
For lowest colored products, it is desirable to maintain a certain minimum 
level of water in the reaction mixture at all times. For example, when 
glucose monohydrate is the starting material, this water retention helps 
solubilize the glucose, prevents the degradation of the monosaccharide, 
which could otherwise accelerate, and slows down color body forming 
condensation. In conjunction with maintaining the vacuum pressure within a 
specified range, it has been found that use of glucose monohydrate as the 
monosaccharide starting material helps ensure that a preferred amount of 
water will be present in the mixture at the time the reaction is started. 
When glucose monohydrate is used as the monosaccharide that is combined 
with the alcohol, vacuum is applied at a pressure between about 20 mm Hg 
and about 100 mm Hg, preferably between about 30 mm Hg and about 60 mm Hg. 
This material cannot be heated or reacted directly with the higher 
alcohols in the presence of the acid catalyst because of the large amount 
of water initially present in the mixture. The presence of this 
combination of water and acid could cause the production of unwanted 
by-products --in particular melted and/or agglomerated dextrose or 
polydextrose --or could retard the reaction because of its reversibility. 
To remove the excess water, the mixture is heated, in the absence of acid, 
for between about 0.5 and about 2 hours, until most of the water of 
hydration is evaporated. The temperature applied to evaporate the water 
preferably is between about 60.degree. C. and about 70.degree. C. Although 
most of the water is removed by evaporation, thus ensuring that 
agglomerated dextrose formation will not occur, enough water is retained 
in the mixture, such as between 0.1% and 0.25% based upon the weight of 
the reaction mixture, to ensure that later glucose degradation and 
polymerization of dehydration products is minimized. 
The mixture is then heated to a temperature preferably between about 
90.degree. C. and about 120.degree. C., over a period of between about 0.5 
and about 1.5 hours. The catalyst is then added to start the reaction. 
After the reaction begins, the water produced is eventually balanced by 
the water removed by evaporation. When this steady state is reached, 
enough water remains in the reaction mixture to inhibit glucose 
degradation and polymerization of dehydration products. 
If anhydrous glucose is used instead of glucose monohydrate as the 
monosaccharide starting material, there will be little water in the 
mixture, before the reaction begins. After the reaction begins, water will 
gradually build up in the reaction mixture until the water produced 
becomes balanced by the water evaporated. At this time, the reaction 
mixture includes enough water, probably about 0.1% based upon the weight 
of the reaction mixture or less, to inhibit glucose degradation. 
It should be appreciated that the actual amount of water present in the 
reaction mixture as the reaction takes place depends upon the pressure, 
type of alcohol used, the temperature applied and may also depend upon the 
monosaccharide starting material. 
It should also be appreciated that when glucose monohydrate is used as the 
monosaccharide starting material, instead of anhydrous glucose, the amount 
of water required to prevent or minimize glucose degradation is present in 
the mixture prior to the beginning of the reaction; whereas when anhydrous 
glucose is the monosaccharide starting material, the amount of water 
needed to help solubilize glucose and prevent or minimize glucose 
degradation may not be generated until after the reaction has proceeded 
for a period of time. 
When glucose or glucose monohydrate is used as the monosaccharide starting 
material, it has been found that an acceptable product may also be 
produced without having to allow the reaction to proceed until 
substantially all of the glucose has reacted. As an alternative to 
allowing the reaction to progress to completion, which for a glucose/ 8 to 
18 carbon straight chain alcohol blend may require from about 2 to about 
10 hours, one may choose to allow the reaction to proceed until, for 
example, about 0.1% to about 3% of the glucose starting material remains. 
The time needed to achieve this extent of reaction would be from about 1.5 
to about 6 hours when an 8 to 18 carbon straight chain alcohol is blended 
with the glucose. The advantage from shortening the reaction time is that 
the less time the reaction proceeds, the more kinetically controlled the 
process and the lesser the amount of undesirable by-products produced. 
To ensure that the remaining glucose will not react to produce unwanted 
by-products, an amount of NaBH.sub.4 (sodium borohydride) may be added. 
Functionally, the NaBH.sub.4 reduces the excess glucose to sorbitol, and 
other reducing sugars to their corresponding alditols. Preferably at least 
about 1 gram of NaBH.sub.4 is added for every 10 to 20 grams of excess 
glucose. Using NaBH.sub.4 to hydrogenate the excess glucose has been found 
in some cases to be more efficient than to bleach the product that would 
otherwise result if the glucose had not been converted to sorbitol. 
In ascertaining and/or quantifying the color (e.g., the relative darkness 
or lightness) characteristics of aqueous glycoside solutions, such as are 
produced in the process of the present invention, it is convenient to 
utilize the extinction coefficient of the glycoside material of interest 
using a suitable spectrophotometer (e.g., a Spectronic 20) over a path 
length of 1 cm and using 470nm wavelength light. Since the extinction 
coefficient is essentially a measure of the ability of the glycoside 
solution of concern to absorb light as opposed to transmitting same, small 
extinction coefficients correspond to substantially colorless glycoside 
solutions. Accordingly, the process of the present invention has the 
effect of producing an alkylglycoside product having a reduced extinction 
coefficient. 
The term "extinction coefficient" as used herein refers to the calculated 
absorbance of a theoretical solution containing one gram of solid material 
per cm.sup.3 of solution measured as described above and calculated 
according to the following formula: 
While not being a required or overriding feature or parameter of the 
present invention, it can be stated as a general point of reference that 
dark colored glycoside solutions, such as are produced in other processes 
for making an alkylglycoside product, can have extinction coefficients of 
over 20, whereas the extinction coefficient of the alkylglycoside product 
made in the present invention is generally less than 2.5, and more 
typically less than 1.0. 
As an alternative to the use of glucose monohydrate as the starting 
material in the process of the present invention, a butyl 
glycoside/glucose mixture may be used as the monosaccharide starting 
material. Such a mixture may be made by admixing butanol with glucose, 
preferably in a butanol to glucose molar ratio of about 2.5 to about 8.0. 
When glucose monohydrate is used as the monosaccharide that is combined 
with butanol, vacuum is applied at a pressure between about 100 mm Hg and 
about 300 mm Hg, preferably between about 125 mm Hg and about 285 Hg. To 
remove a portion of the water of hydration initially present in the 
mixture, the mixture is heated for between about 0.5 and about 2.0 hours. 
The temperature applied to distill the water is preferably between about 
60.degree. C. and about 90.degree. C. About 0.2% to about 2.0% water, 
based on the total weight of the mixture, remains in the mixture. Both 
water and butanol are removed by distillation under these conditions. The 
distilled butanol may be returned to the mixture after dehydration, 
preferably by distillation. 
The pressure may then be increased to between about 450 mm Hg to about 750 
mm Hg. The mixture is then heated over a period of between about 0.5 hours 
to about 1.5 hours to a temperature between about 100.degree. C. and about 
115.degree. C. An acid catalyst that may be completely neutralized with 
stoichiometric amounts of an alkaline substance is added in an amount 
between about 0.5% and about 2.0%, based on the amount of glucose used, on 
a molar basis. The reaction will produce a butyl glycoside product and a 
water by-product. The reaction should be continued until the dextrose has 
dissolved. This should require approximately 1 to 5 hours. During this 
period, both water and butanol are removed by distillation. The distilled 
butanol may be returned to the reaction mixture after dehydration, 
preferably by distillation. 
Alternatively, a butyl glycoside/glucose mixture may be made by admixing 
butanol with anhydrous glucose or glucose monohydrate, preferably in a 
butanol to glucose molar ratio of about 2.5 to about 8.0, along with an 
acid catalyst that may be completely neutralized with stoichiometric 
amounts of an alkaline substance. Because of the water of hydration 
initially present in the mixture when glucose monohydrate is used, and 
because the reaction will produce a butyl glucoside product and a water 
by-product, the pressure must be reduced to a level sufficient to enable 
removal of a substantial amount of water. The pressure applied will allow 
about 0.2% to 2.0% water, based upon the total weight of the reaction 
mixture, to remain in the mixture, and preferably should be between about 
450 mm Hg to about 750 mm Hg. The catalyst should be added in an amount 
between about 0.5% and about 2.0% based on the amount of glucose used, on 
a molar basis. 
After the butanol, glucose, and catalyst have been combined and the 
pressure reduced, the mixture is heated to a temperature between about 
100.degree. C. and about 115.degree. C., to enable the butanol to react 
with the glucose. The reaction should be continued until the dextrose has 
dissolved. This should require approximately 1 to 6 hours. During this 
period, both water and butanol are removed by distillation. The distilled 
butanol may be returned to the reaction mixture after dehydration, 
preferably by distillation. 
Once the glucose has dissolved, this butyl glycoside/glucose mixture, which 
makes up the starting material for the process described in this 
embodiment, should contain between about 24% and 50% butyl glycosides, 
between about 1% and about 5% glucose, and between about 45% and 75% 
butanol. To this mixture may then be added a monohydric alcohol containing 
8 -20 carbons. This 8 -20 carbon monohydric alcohol replaces the butanol 
as it is being distilled from the reaction mixture. The ratio of alcohol 
to the glucose, that was admixed with the butanol, is about 2.5 to about 6 
on a molar basis. During this step in the process the pressure is 
preferably reduced to in the process the pressure is preferably reduced to 
between about 20 mm Hg and about 100 mm Hg at a relatively constant rate 
over a period of between about 1.5 to about 4 hours. This enables the 
removal of a substantial amount of the butanol from the reaction mixture. 
After the 8 -20 carbon alcohol is added, the reaction preferably proceeds 
for an additional 0.5 to 6 hours. After this period of time, the residual 
butanol should have been reduced to between about 1% and about 2.5% of the 
reaction mixture, by weight, and the residual butyl glucosides (on a dry 
solids basis) should have been reduced to between about 2% and about 8% of 
the reaction mixture, by weight. At this point in the process, a 
sufficient amount of an alkaline substance, preferably sodium hydroxide, 
is added to neutralize the catalyst. The residual unreacted alcohol is 
then removed from the reaction mixture through evaporation or some 
equivalent means. The resulting product should contain between about 80% 
and about 95% alkylglycosides, about 2% and about 13% polydextrose, about 
1% and about 3% nonpolar by-products, and about 2% and about 8% butyl 
glucosides.

The following examples illustrate some of the advantages of the present 
invention. 
EXAMPLE 1 
To a 2-liter, four-neck flask equipped with an overhead stirrer, 
thermometer and addition funnel, was added 732.5 grams (5.0 moles) of a 
commercially available mixture comprised of about 44 parts of n-octanol, 
55 parts of n-decanol and some n-hexanol and n-dodecanol. Stirring was 
started and 396 grams (2.0 moles) of glucose monohydrate was added. Vacuum 
was applied and the pressure was reduced to about 50 mm Hg. The mixture 
was then heated for about 0.5 to 2 hours until most of the water of 
hydration was evaporated, while the pot temperature was about 60.degree. 
C. to 65.degree. C. The mixture was then heated until it reached about 
100.degree. C. At this point, 35 ml water and 2 ml alcohol were collected. 
At this point in the process, it is estimated that the reaction mixture 
retained about 0.18% water, as measured by a Karl Fischer titration, based 
upon the weight of the total mixture. Then 3.80 grams (0.020 moles) of 
p-toluene sulfonic acid monohydrate catalyst was added as a 50% solution 
(7.60 grams) in wet 8 -10 carbon alcohol (1.52 grams H.sub.2 O and 2.28 
grams alcohol). During the next 4 to 5 hours, distillate was collected 
which was comprised of about 36 ml of a lower water layer and about 4 ml 
of an upper or wet alcohol layer. The resulting mixture was hazy, but free 
of dense insolubles. The yellowish reaction mixture was found to contain 
less than about 0.1% reducing sugars. 
To this mixture was then added 1.60 grams (0.020 moles) of a 50% aqueous 
solution of sodium hydroxide. Ten minutes later an aliquot of 2.17 grams 
of reaction mixture was diluted to 10 ml with 1:1 isopropyl alcohol (IPA): 
water (1.0 gram dry solids/10 ml). This solution was found to have a pH of 
about 7.0. A reverse phase chromatographic analysis showed that the 
reaction mixture itself contained 53.8% alcohol and 21.5% monoglucosides. 
Evaporation of the fatty alcohol using a Leybold Heraeus thin film 
evaporator, using an oil temperature of about 165.degree. C. and a 
pressure of about 1 mm Hg, produced a straw yellow residue. This residue, 
in dry solid form, consisted of about 0.8% sodium tosylate, about 3.3% 
polydextrose, about 2.0% nonpolar reaction by-products, and about 93.9% 8 
-10 carbon alkylglucosides. The DP of the alkylglucosides, using NMR, 
liquid chromatography, and gas chromatography methods, was calculated to 
be about 1.65. When dissolved in water (70% dry solids) the solution 
became a crystal clear light amber solution. 
Using a Spectronic 20 (Bausch and Lomb) at 470nm, this solution was found 
to have an extinction coefficient of about 0.6. 
EXAMPLE 2 
To a 4-liter, four-neck flask equipped with an overhead stirrer, 
thermometer and addition funnel, was added 2328 grams (12.0 moles) of a 
commercially available mixture, i.e., Neodol 23 (Shell Oil Co.), which was 
comprised of about 43 parts n- and branched 12 carbon alcohols, 55 parts 
of n- and branched 13 carbon alcohols, and smaller amounts of 11, 14 and 
15 carbon alcohols. Stirring was started and 396 grams (2.0 moles) of 
glucose monohydrate was added. Vacuum was applied and the pressure was 
reduced to about 50 mm Hg. The mixture was then heated for about 0.5 to 2 
hours until most of the water of hydration was evaporated, while the pot 
temperature was about 60.degree. C. to 65.degree. C. The mixture was then 
heated until it reached about 105.degree. C. At this point, 35 ml water 
and 0.1 ml alcohol were collected. At this point in the process, the 
reaction mixture retained about 0.13 % water, based upon the weight of the 
total mixture. Next, 3.80 grams (0.020 moles) of p-toluene sulfonic acid 
monohydrate catalyst was added as a 50% solution (7.60 grams) in wet 
Neodol 23 alcohol (1.52 grams H.sub.2 O and 2.28 grams alcohol). During 
the next 8 to 9 hours, distillate was collected which was comprised of 
about 36 ml of a lower water layer and about 4 ml of an upper or wet 
alcohol layer. The resulting reaction mixture was hazy, but free of dense 
insolubles. The yellowish reaction mixture was found to contain less than 
about 0.1% reducing sugars and less than 0.1% water. 
To this mixture was then added 1.60 grams (0.020 moles) of a 50% solution 
of sodium hydroxide in water. Ten minutes later an aliquot of 4.5 grams of 
reaction mixture was diluted to 10 ml with 60:40 IPA:H.sub.2 O (1.0 gram 
dry solids/10 ml). This solution was found to have a pH of about 6.9. A 
reverse phase chromatographic analysis showed that the crude reaction 
mixture contained 78% alcohol and 14.1% monoglucosides. Evaporation of the 
fatty alcohol using a Leybold Heraeus thin film evaporator, using an oil 
temperature of 205.degree. C. and a pressure of about 1 mm Hg, produced a 
straw yellow residue. This residue, in dry solid form, consisted of about 
0.7% sodium tosylate, about 3.0% polydextrose, about 2.0% nonpolar 
reaction by-products, and about 94.3% alkylglucosides. The average degree 
of polymerization of the alkylglucosides, using NMR, liquid chromatography 
and gas chromatography methods, was calculated to be about 1.32. When 
dissolved in water (60% dry solids) the solution became a crystal clear 
light amber solution. 
Using a Spectronic 20 at 470nm, the solution was found to have an 
extinction coefficient of about 0.7. 
The following Examples 3 and 4 may also be performed and should produce the 
following results. 
EXAMPLE 3 
To a 4-liter, four-neck flask equipped with an overhead stirrer, 
thermometer and addition funnel, was added 2134 grams (11 moles) of a 
commercially available mixture comprised of about 43 parts of n- and 
branched C.sub.12 alcohol parts and 55 parts of n and branched C.sub.13 
alcohol, along with small amounts of C.sub.11, C.sub.14 and C.sub.15 
alcohols. Stirring was started and 396 grams (2 moles) of glucose 
monohydrate added. Vacuum was then applied and the pressure reduced to 
about 90 mm Hg. The mixture was then heated for about 0.5 to 2 hours until 
most of the water of hydration was evaporated, while the pot temperature 
was about 65.degree. C to 70.degree. C. The mixture was then heated until 
it reached about 105.degree. C. At this point, 29 ml water and 0.2 ml 
alcohol was collected. At this point in the process, it is estimated that 
the reaction mixture retained about 0.25% water, based upon the weight of 
the total mixture. 3.80 grams (0.020 moles) of p-toluene sulfonic acid 
monohydrate catalyst was then added as a 50% solution (7.60 grams) in wet 
Neodol 23 (Shell Oil Co.) (1.52 grams H.sub.2 O and 2.28 grams alcohol). 
During the next 9 -10 hours, distillate was collected which was comprised 
of about 36 ml of a lower water layer and about 3 ml of an upper or wet 
alcohol layer. The resulting mixture was hazy, but free of dense 
insolubles. The yellowish reaction mixture contained less than about 0.3% 
reducing sugars and about 0.3% water. 
To this mixture was then added 1.60 grams (0.020 moles) of a 50% solution 
of sodium hydroxide in water. Ten minutes later a 4.2 gram aliquot of the 
reaction mixture was dissolved in 60/40 IPA/H.sub.2 O (1.0 gram dry 
solids/10 ml). This mixture had a pH of about 6.8. A reverse phase 
chromatographic analysis of the reaction mixture showed that the mixture 
contained 76% alcohol and 13.6% monoglucosides. Evaporation of the fatty 
alcohol using a Leybold Heraeus thin film evaporator, using an oil 
temperature of 207.degree. C. and a pressure of about 1 mm Hg, produced a 
straw yellow residue. This residue, in dry solid form, consisted of about 
0.7% sodium tosylate, about 7% dextrose plus polydextrose, about 2% 
nonpolar reaction by-products, and about 90.3% alkylglucosides. The 
average degree of polymerization of the alkylglucosides, using NMR, liquid 
chromatography and gas chromatography methods, was about 1.35. When 
dissolved in water (60% dry solution) the solution became a crystal clear 
light amber solution. 
Using a Spectronic 20 at 470nm, the solution had an extinction coefficient 
of about 0.5. 
EXAMPLE 4 
To a 1-liter, four-neck flask equipped with an overhead stirrer, 
thermometer and addition funnel, may be added 530 grams (7.15 moles) 
butanol. Stirring may be started and 230 grams (1.16 moles) of glucose 
monohydrate added. Vacuum may be applied and the pressure may be reduced 
to about 125 mm Hg. The mixture should then be heated at 70.degree. C. for 
about 0.5 hours. 77 ml of wet butanol and 8 ml of water should be removed 
while an equal volume of dry butanol is added back to the mixture. The 
pressure should then be changed to 660 mm Hg and the mixture heated to 
110.degree. C. At this point in the process, it is expected that the 
mixture will retain about 0.8% water, based on the weight of the total 
mixture. 2.21 grams (0.0116 moles) of p-toluene sulfonic acid monohydrate 
catalyst should then be added as a 50% solution (4.42 grams) of wet 
butanol (0.22 grams water and 1.99 grams butanol). During the next 40 
minutes, distillate should be collected which should be comprised of about 
170 ml of wet butanol while an equal volume of dry butanol is added back 
to the reaction mixture. The resulting mixture should be yellowish and 
hazy, but free of dense insolubles. The resulting mixture should contain 
about 31% butyl glucosides, 3% glucose, 65% butanol, and 1% water. 557 
grams (3.48 moles) of a commercially available mixture, i.e., Neodol 91 
(Shell Oil Co.), which is comprised of about 1 part, n- and branched 8 
carbon alcohols, 18 parts n- and branched 9 carbon alcohols, 46 parts of 
n- and branched 10 carbon alcohols, and 35 parts of n- and branched 11 
carbon alcohols should be added uniformly over the next 3 hours. During 
this period, 685 ml of wet butanol should be uniformly removed by 
distillation by uniformly decreasing the pressure to 20 mm Hg. The 
reaction is continued at these conditions for an additional 1.5 hours 
during which time an additional 27 ml of distillate should be collected. 
The resulting mixture should be slightly hazy, but free of dense 
insolubles. The light brown reaction mixture should contain less than 
about 0.1 % reducing sugars. 
The mixture may then be neutralized by the addition of 0.928 grams of a 50% 
aqueous solution of sodium hydroxide (0.0116 moles). In order to determine 
the pH of the neutralized mixture, ten minutes later, a 2.6 gram aliquot 
(1.0 gram dry solids) of the reaction mixture may be diluted to 10.0 ml 
with 1:1 IPA:H.sub.2 O and the pH can be measured. The solution should 
have a pH of 6.8. A reverse phase chromatographic analysis should show 
that the mixture contains 62.8% alcohol and 20.0% monoglucosides. 
Evaporation of the fatty alcohol using a Leybold Heraeus thin film 
evaporator, using an oil temperature of 165.degree. C. and a pressure of 
about 1 mm Hg, should produce a light brown residue. This residue, in dry 
solid form, should consist of about 0.7% sodium tosylate, about 7% 
polydextrose, about 2% nonpolar reaction by-products, about 7% 
butylglucosides, and about 83.3% 8 -10 carbon alkylglucosides. The average 
degree of polymerization of the 8 -10 carbon alkylglucosides, using 
previously described methods, should be calculated to be about 1.6. When 
dissolved in water (70% dry solution) the solution is expected to become a 
crystal clear light amber colored solution. 
Using a Spectronic 20 at 470nm, the solution is expected to have an 
extinction coefficient of less than about 2.5. 
EXAMPLE 5 
For comparison purposes, a product was made following the process steps of 
Example 1, but using 2 moles anhydrous glucose, 5 moles alcohol and 40 
mmoles of a sulfuric acid catalyst instead of the glucose monohydrate and 
p-toluene sulfonic acid monohydrate catalyst. Because anhydrous glucose 
was used in this example instead of glucose monohydrate, the reaction 
mixture was heated directly to about 100.degree. C., without the initial 
pre-evaporation step that is needed to remove most of the water from the 
glucose monohydrate when that is the monosaccharide starting material. 
Prior to neutralization with a stoichiometric amount of sodium hydroxide 
(80 mmoles) the SO.sub.3 containing moieties in the reaction product 
included estimated: 
______________________________________ 
22 mmoles sulfuric acid, 
13.34 mmoles alcohol sulfuric acid esters, 
3.24 mmoles alkylglucoside sulfuric acid esters, 
1.42 mmoles glucoside sulfuric acid esters; 
______________________________________ 
After neutralization, the sulfate containing moieties in the resulting 
product included approximately: 
______________________________________ 
22 mmoles sodium sulfate, 
13.34 mmoles sodium alkylsulfates, 
3.24 mmoles sodium alkylglucoside sulfates, 
1.42 mmoles sodium sulfated glucose. 
______________________________________ 
Also included were about 18.0 mmoles sodium hydroxide. 
In contrast to these reaction products, when the p-toluene sulfonic acid 
catalyst of Example 1 is used, in an amount of 20 mmoles, neutralization 
with 20 mmoles sodium hydroxide produces 20 mmoles sodium tosylate, 
without any esterified by-products, such as are produced when a sulfuric 
acid catalyst is used. 
The composition of the final product of Example 5, after wiped film 
evaporation of the residual alcohol, was as follows: 
______________________________________ 
about 0.7% sodium sulfate, 
about 1.3% sulfated glucose moieties and 
alcohols, 
about 1.0% sodium salts of carboxylic acids, 
about 7.7% polydextrose, 
about 2.0% nonpolar reaction by-products, 
and 
about 87.3% 8-10 carbon alkylglucosides. 
______________________________________ 
Using a Spectronic 20 at 470nm, this solution was found to have an 
extinction coefficient of over 20. This corresponds to a dark coffee color 
for the resulting product, in contract to the substantially colorless 
product such as is produced following the process shown in Example 1. 
EXAMPLE 6 
As an alternative to the process described in Example 1, the reaction may 
be allowed to proceed for 3 to 3.5 hours rather than for 4 to 5 hours. In 
this alternative process, the resulting mixture would include about 1.8% 
unreacted glucose. To this mixture should be added about one gram of 
NaBH.sub.4 in aqueous NaOH. The NaBH.sub.4 should reduce the unreacted 
glucose to sorbitol. 
Following the isolation steps of Example 1, the resulting residue should, 
in dry solid form, consist of about 1.3% of a mixture of sodium tosylate 
and borate, about 6% of a mixture of sorbitol and polydextrose, about 2% 
nonpolar reaction by-products, and about 90.7% 8 -10 carbon 
alkylglucosides. The average degree of polymerization of the 
alkylglucosides should be about 1.59. Like the Example 1 product, this 
product, when dissolved in water (70% dry solids), should produce a 
crystal clear light amber solution. 
Using a Spectronic 20 at 470 nm, this solution should show an extinction 
coefficient of about 0.5. 
Alternatively, the reaction mixture may be neutralized with NaOH and 
evaporated prior to the aqueous solution, which contains some of the 
unreacted glucose, being reduced with sodium borohydride. In this process, 
a significant portion of the glucose may be thermally dehydrated to 
anhydro glucose during wiped film evaporation. Addition of the sodium 
borohydride after the neutralization and evaporation steps should produce 
a caustic stable product. 
Additional advantages and modifications will readily occur to those skilled 
in the art. The invention in its broader aspects is therefore not limited 
to the specific details, representative apparatus, and illustrative 
examples. It is apparent that the proportion of reactiants, time of 
reaction, vacuum pressure, reaction temperature, and catalyst 
concentration may be varied, as may be the types of sugars, alcohols, and 
neutralizing agents. Accordingly, departures may be made from the 
described details without departing from the spirit or scope of the 
disclosed general inventive concept.