WO2002038269A1

WO2002038269A1 - An alkoxylenation catalyst and a method to manufacture the alkoxylenation catalyst

Info

Publication number: WO2002038269A1
Application number: PCT/PL2001/000020
Authority: WO
Inventors: Wieslaw Hreczuh; Kazimierz Pyzalski; Zbigniew Tomik; Janusz Wackowski; Krystyna Rolnik; Marek Lukosek; Jan Szymanowski; Wladyslaw Domarecki; Andrzej Andrysiak; Grazyna Kaczor; Barbara Naraniecka; Renata Fiszer
Original assignee: Instytut Ciezkiej Syntezy Organicznej Blachownia
Priority date: 2000-11-13
Filing date: 2001-03-13
Publication date: 2002-05-16
Also published as: PL343853A1; AU2001241297A1

Abstract

The ethoxylation catalyst is in the form of a visually homogeneous, liquid suspension or a homogeneous paste and contains the following: calcium salts of low molecular carboxylic or hydroxycarboxylic acids or hydrates of the former, sulfuric acid and an alcohol and/or an ester, or products of their reciprocal reactions, being formed during homogenization, the calcium salt and sulfuric acid having a total concentration in the range 10-65 % by weight. In the method to manufacture the alkoxylenation catalyst, the calcium salt of a low molecular carboxylic or hydrocarboxylic acid or a hydrate (I) of the former is mixed with sulfuric acid (II), and alcohol and/or ester (III) at a temperature in the range 283-368 K, the components (I) and (II) at concentrations in the range form 10 % to 65 % by weight, as well as their proportions, temperatures, time and intensity of mixing eing so selected as to obtain a product in the form of a visually homogeneous, liquid suspension or a visually homogeneous paste, for use as a catalyst in the process of alkoxylenation.

Description

An alkoxylenation catalyst and a method to manufacture the alkoxylenation catalyst

This invention relates to a method to obtain a catalyst for alkoxylenation, specifically, a catalyst for ethoxylenation and propoxylenation of organic compounds having a labile hydrogen atom or an ester bond. The alkoxylenation process has been well known and used commercially. The catalysts commonly used are alkaline metal compounds, such as sodium or potassium hydroxides and alcoholates. The reaction will always produce a polydisperse mixture of homologs and usually a portion of an unreacted reactant. This is frequently regarded as a disadvantage of the resulting products, specifically in the case of alcohol ethoxylates where, if a conventional alkaline catalyst is used, then the amount of homologs whose polyaddition degrees are much different from an average degree of ethoxylenation with respect to the number of the attached alkylene oxide groups is particularly high and the initial reactant leaves a significant amount of unreacted residue.

Therefore, various attempts have been made for years to obtain in ethoxylenation products an increased content of an adduct with a desirable narrow range of polyaddition degrees, that is, an adduct whose number of the attached alkoxylene groups is similar to the average degree of ethoxylenation, and to obtain a reduced amount of unreacted residue and less homologs with polyaddition degrees being much different from the average degree of ethoxylenation.

Initially, attempts to reduce the quantity of homologs with polyaddition degrees being much different from the average degree of polyaddition were principally made by way of vacuum distillation: the unreacted portion of the reactants as well as low molecular oligoadducts having one, two or three ethoxylene- groups were separated from the conventional product of ethoxylenation having a so- called broad homolog distribution (as described in US Pat. 3682849, GB Pat. 1462134, US Pat. 4441881). Unfortunately, the method to physically separate low molecular fractions of ethoxylates leaves too much of undesirable, high molecular homologs in the product. Chemical methods to obtain a narrowed fractional composition of ethoxylates have been used as well. It is commonly known that narrow distributions of homologs in ethoxylenation products, close to Poisson distribution, may be obtained if compounds such as Lewis acids are used as the catalyst. Although acid catalysts enable relatively narrow homolog distributions to be obtained, a number of by-products, mainly polyethoxylene glycols and dioxane, are known to be formed in such acid- catalyzed reactions.

Sodium and potassium compounds are widely used as catalysts in alkoxylenation reactions. Among these, sodium and potassium hydroxides are most commonly used and are known to provide products with low concentrations of polyethylene glycols and dioxane. Unfortunately, products obtained in the presence of such conventional catalysts, specifically where alcohol type reactants are used, have the disadvantage of the reactant leaving in the reaction product too high a content of residue that has failed to react with alkylene oxide, and a high quantity of homologs with polyaddition degrees being much different from the average degree of ethoxylenation. Moreover, alkaline metal catalysts will be effective in alkoxylenation of reactants containing a group with a so- called labile hydrogen group but they will not be effective in alkoxylenation of an ester group. Disclosed in the EP Pat. 0092256 is a method for the synthesis of ethoxylenated alcohols, catalyzed by calcium ethanolate and sulfuric acid. The components of the catalyst were added in catalytically effective quantities, directly either to the reactant subjected to ethoxylenation or to an intermediate low molecular alcohol system; the said catalytically effective quantities were used as the catalyst without being substantially diluted, that is, without lowering their concentration in the reaction medium relative to the intermediate solution. The use of the catalyst at concentrations in the range from 0.1% to 1% relative to the ethoxylated alcohol was claimed.

Similarly, the use of Ca and Mg alcoholates as catalysts is disclosed in the US Pat. 4396779 and US Pat. 4465877, respectively. In the processes disclosed in the US Pat. 4465877 and EP Pat. 0082569, an activator in the form of a separately prepared additional amount of the ethoxylated alcohol is used in the amount of 2% by mole relative to the alcohol subjected to ethoxylenation, whereby products with narrow homolog distributions, that is, ones having a relatively low quantity of homologs with degrees of ethoxylenation being much different from the average degrees of polyaddition are obtained. However, since alcoholates of metals are generally compounds of poor stability, their preparation and application as catalysts is difficult. The preparation of the said group of alcoholate catalysts usually involves addition of certain intermediate steps by separately introducing a more stable metal salt or, for instance, metallic calcium or magnesium into the reactive low molecular alcohol to obtain a low molecular alcoholate, followed by a replacement reaction effected by admixing a fatty alcohol and evaporating the low molecular alcohol at an elevated temperature to obtain a higher alcohol alcoholate.

The method disclosed in the EP Pat. 0085167 relates to the manufacture of an ethoxylenated alcohol having a narrow homolog distribution, with the use of calcium acetate or magnesium acetate as catalysts, introduced directly to the ethoxylenated alcohol at concentrations in the range 0.05% to 5% by weight of the alcohol. However, the reaction with ethylene oxide runs rather slowly in this case, making the synthesis a lengthy process. Even though the reaction with alkylene oxide is made to run faster by increasing the concentration of calcium acetate or magnesium acetate, the homolog distribution remains unaffected in this case; although narrower than in a process where alkaline catalysts such as KOH are used, the homolog distribution is still rather broad.

A catalyst for ethoxylenation with unusually high catalytic activity, based on calcium and providing a narrow homolog distribution is disclosed in the US Pat. 4835321 and US Pat. 4775653. The said group of catalysts are mixtures of calcium oxide or hydroxide with aluminum alcoholates and sulfuric acid. Preparation of the said catalyst involves, among other things, preliminary activation at an elevated temperature, even as high as 513 K, making it a burdensome and costly process.

Disclosed in the US Pat. 4946984 is the application of calcium sulfate as catalyst in the preparation of ethoxylates of alcohols with narrow homolog distributions. According to the Examples in the said patent specification, 1% by weight of calcium sulfate relative to the alcohol subjected to ethoxylenation was used, however the resulting conversion time of ethylene oxide is not indicated. The present authors have carried out a series of syntheses where calcium sulfate was introduced directly to the reactant subjected to ethoxylenation, in amounts below 0.1% relative to the lauryl alcohol subjected to ethoxylenation, and found the catalyst to show a relatively low catalytic activity with respect to the rate of the reaction; 610 g of ethylene oxide was added within 1217 minutes at 438 K to obtain a product whose average degree of polyaddition was 10. Particularly low reaction rates were obtained in ethoxylenation of fatty acid methyl esters catalyzed by calcium sulfate where it was used at 0.15 % relative to the rape seed oil acid methyl ester; merely 83 g of ethylene oxide was added to the reactor within 315 minutes to obtain a product whose average degree of polyaddition was 1.9. Resulting from that, it was concluded that calcium sulfate has no practical potential as a catalyst for ethoxylenation in the range of concentration discussed herein. One of a series of similar catalysts for ethoxylenation, represented by the EP Pat. 0361618, is a system comprising calcium compounds, mainly calcium oxide, calcium hydroxide and, optionally, calcium salts of carboxylic acids activated by dissolution or partial dissolution in a bi-functional solvent (activator), described by the general formula Z-X-Q-Y-Z' where Q denotes an organic radical, X and Y denote oxygen, sulfur or nitrogen while X may be identical to Y; Z and Z' denote hydrogen or organic radical, while Z may be identical to Z'. Ethylene glycol is an example of the said activator described by the formula Z-X-Q-Y-Z'. An oxy-salt modifier is added to the catalyst and, following its thermal treatment, the catalyst is transferred to the reactant that is subjected to ethoxylenation, to remove the excess Z-X-Q-Y-Z' activator at an elevated temperature. The resulting catalyst provides a narrow homolog distribution of the products of fatty alcohol ethoxylenation. Unfortunately, the complexity of the method to prepare the catalyst and the necessity to subject it to thermal treatment seem to make it a costly and laborious process.

Disclosed in the Polish patent PL 166429 is the use, as a catalyst, of mixtures comprising calcium acetate and, optionally, magnesium acetate and sulfuric acid, added directly to the reactor in catalytically effective quantities. However, as shown in the examples provided, low conversion rates of ethylene oxide, around 1 mole of ethylene oxide per mole of alcohol per hour were obtained even for rather high concentrations of the catalyst (totaling, as a sum of active ingredients, about 0.6 % relative to the fatty alcohol). This is probably due to the poor solubility of calcium and magnesium acetates in the reaction medium.

Disclosed as an effective catalyst in the Polish patent PL 171663 is a mixture comprising calcium sulfate, calcium acetate, a low molecular calcium alcoholate and a crystalline phase being in the form of organic calcium and sulfur compounds and characterized by the presence of the following strong and medium reflections of a crystalline surface, at the following distances in the X-ray diffraction diagram: 12.1 -very strong, δ.1-average, 3.6-average, 3.49-strong, 3.43, 3.33-average, 3.00-strong, 2.80-average, as well as a mixture of other crystalline derivatives of sulfur and calcium and low molecular alcohols which compounds are neutral to the course of the synthesis process. It was found that when used in ethoxylenation of alcohols, the said catalyst provides products having a very low content of homologs whose polyaddition degrees are much different from the average degree of ethoxylenation. On the other hand, when added in a catalytically effective quantity directly to the reactant subjected to ethoxylenation in a crystalline form, the catalyst will not readily dissolve. in the reaction medium, necessitating higher concentrations and extending the duration of the synthesis initiation step.

Before recently, it was commonly believed that for an effective selective ethoxylenation reaction to proceed it was necessary to have a reactant containing a so-called labile hydrogen atom. Not before the nineties was the possibility of direct ethoxylenation of fatty acid alkyl esters in the presence of a new type of catalysts reported in literature. The reaction is made to run effectively by selectively inserting an ethylene oxide molecule between the carbonyl carbon atom and the ester bond alkoxy group. Disclosed in the EU Pat. 033529 is the possibility of direct ethoxylenation of fatty esters with participation of a catalyst obtained from a group comprising hydroxides, oxides and alcoholates of alkaline metals or alkaline earth metals. According to the US Pat. 5220046 or its version WO 93/04030, a calcium catalyst was used in a mixture with addition of an ethoxylenated alcohol, inorganic acid and aluminum or titanium alcoholate. Preparation of the catalyst, also disclosed in the US Pat. 4775653 and US Pat. 4820673, is a complex and lengthy process, affecting significantly the costs of large-scale preparation of the catalyst.

Disclosed in the German patent DE 3914131 is calcinated hydrotalcide as an effective catalyst in ethoxylenation of esters and its further modification, obtained by using co-catalysts in the form of zinc hydroxide, alkaline earth metal salts such as magnesium carbonate or tin compounds disclosed in the German patent DE 19611999. Claimed in the US Pat. 5374750 is application of magnesium oxide in a mixture comprising from 0.1% to 10% of a specially prepared metal ion from the group comprising Al³⁺, Ga³⁺, ln³⁺, Tl³⁺, Co³⁺, Sc³⁺, La³⁺, and Mn²⁺. Relatively high temperatures of activation, even as high as 1223 K, are required in the preparation of the said catalyst. A bi-metallic catalyst comprising magnesium compounds and oxides of the elements of groups IV and VI of the Periodic Table, such as zinc or antimony, is described in the Japanese Pat. 08323200.

The so-called unconventional catalysts referred to above and used for making ethoxylated alcohols with narrow homolog distributions were frequently observed to show catalytic activities in reactions of ethylene oxide with fatty acid methyl esters. In many cases, the catalysts were further modified to improve reaction rates, reduce the amounts of by-products or lower reaction temperatures. An example of such procedure is improvement of the hydrotalcide catalyst described in the German Pat. DE 3914131 by additional introduction of co-catalysts disclosed in the German Pat. DE 19611999. The same practice was applied to verify the usefulness of an unconventional catalyst for the process to obtain ethoxylenated fatty alcohols with narrow homolog distributions referred to in the Polish patent PL 171663, in the direct ethoxylenation of fatty acid methyl esters. In the direct ethoxylenation of the esters the said catalyst showed a relatively poor activity. The synthesis process proceeded rather slowly even at relatively high concentrations of the catalyst, and the resulting products were characterized by darker coloration, high content of unreacted ethylene oxide and excess content of by-products, including dioxane. Temperatures of 453 K or higher were required to initiate the reaction.

In the case of the above mentioned catalytic systems which provide the so-called narrow homolog distribution in ethoxylenation products and are active in direct ethoxylenation of esters, the catalyst preparation process will as a rule comprise several steps. In many cases, catalytic metal compounds are rendered in a more readily soluble form via alcohol exchange by indirect preparation of low molecular alcoholates or other derivatives of so-called activators, followed by mixing with a fatty alcohol or an ester subjected to ethoxylenation, and evaporating the lower boiling component. Where a so-called catalyst precursor and a catalyst modifier, or promoter, in the form of strong mineral acids or their salts, are introduced directly into the reaction medium, its concentration in the reaction medium must be kept relatively high and, as a rule, it will be necessary to treat it thermally beforehand to obtain the desirable reaction rate.

On the other hand, catalysts in the crystalline form or, more generally, those less readily soluble in the alkoxylenation reaction medium, have so far needed additional thermal treatment to be rendered into a more readily soluble form of alcoholates, or they have been used at elevated concentrations to provide the required catalytic activity.

Unexpectedly, it was found that an alkoxylenation catalyst with very high activity is obtained by preparing a catalyst concentrate by homogenization of calcium salts of low molecular carboxylic or hydroxycarboxylic acids or hydrates of the former (I) and a strong oxy-acid, preferably sulfuric acid (II), in a solution of alcohols or esters (III), where the components (I) and (II) make a total of 10% to 65% by weight of the concentrate added, to obtain a visually homogeneous suspension or paste. Accurate homogenization of the concentrate provides a maximum size reduction and uniform dispersion of the components of the catalyst concentrate, despite their mutually limited solubilities. The effective development of interfacial contact surface of the heterogeneous components of the catalyst concentrate resulting from that, favors the occurrence of desirable physical and chemical changes. Consequently, the alkoxylenation catalyst obtained shows high activity which, at low concentrations, enables very good dispersion in the alkoxylenation reaction medium, to eventually minimize the duration of the reaction initiation and to obtain a high conversion rate of alkylene oxide. The possibility to use the catalyst at very low concentrations has a favorable effect on the quality of the resulting products and helps reduce the possible costs of removal of the catalyst residue. Furthermore, the preparation and storage of the catalyst of the present invention in the form of a concentrate without having to subject it to additional thermal treatment are inexpensive, safe and extremely convenient operations in practice.

In the method of the invention, the alkoxylenation catalyst resulting from the homogenization step is in the form of a visually homogeneous, liquid suspension or a homogeneous paste and it contains:

- calcium salts of low molecular carboxylic or hydroxycarboxylic acids or hydrates of the former,

- a strong oxy-acid, preferably sulfuric acid,

- an alcohol and/or an ester, or products of their reciprocal reactions, being formed on homogenization, a total concentration of the calcium salts and sulfuric acid being in the range from 10% to 65% by weight. The calcium salt is preferably calcium acetate and/or calcium lactate and/or hydrates of the former. The catalyst preferably contains the same alcohol or ester as the one that is subjected to ethoxylenation.

The gist of the method of the invention is that a calcium salt of a low molecular carboxylic and/or hydroxycarboxylic acid and/or a hydrate of the former (I) is mixed with a strong oxy-acid, preferably sulfuric acid (II), and with an alcohol and/or an ester (III) at a temperature in the range 283-368 K, wherein the components (I) and (II) at a concentration in the range 10% to 65%, as well as their proportions, temperatures, time and intensity of mixing are so selected as to obtain a product in the form of a visually homogeneous, liquid suspension or a visually homogeneous paste, for use as a catalyst in the process of alkoxylenation. The calcium salt used is preferably calcium acetate and/or calcium lactate and/or hydrates of the former. The alcohol and/or ester used are preferably the same alcohol or ester as the ones that are subjected to ethoxylenation.

In the method of the invention, the alkoxylation catalyst is obtained as a concentrate in the form of a visually homogeneous liquid or paste by homogenization of so-called active ingredients of the catalyst, which make a total of 10% to 65% by weight of the concentrate added and are introduced to alcohols or esters, the said active ingredients being partially or entirely insoluble in the alcohols or esters, used for making the catalyst concentrate as well as in the reactant subjected to ethoxylenation, and where the said reactant subjected to ethoxylenation may be identical to the alcohols or esters contained in the concentrate. The ingredients of the catalyst concentrate are homogenized to obtain it in the form of a visually homogeneous, liquid suspension or paste, whereupon a concentrate in such form is added, in a catalytically active quantity, to the reactant subjected to ethoxylenation. The active ingredients in the method of the invention are calcium acetate, calcium lactate and/or other calcium salts of low molecular carboxylic or hydroxycarboxylic acids and/or hydrates of the former, and sulfuric acid, as well as products of their reciprocal reactions, being formed during homogenization of the active ingredients referred to hereinabove.

While not attempting to limit the nature of all the changes that occur in the catalyst concentrate during homogenization, it is assumed that the unusually high activity of the resulting alkoxylation catalyst, obtained by the method of the invention in the form of a concentrate, is substantially due to maximum size reduction and dispersion of its insoluble or sparingly soluble components. Owing to the maximum development of an interfacial contact surface of the catalyst components and to their high concentration (from 10 % to 65 % by weight) during homogenization, the occurrence of favorable physical and chemical changes that determine the possibility of efficient utilization of the active ingredients of the catalyst in the reaction medium during alkoxylation is facilitated. Consequently, no additional thermal treatment or removal of any component from the reaction medium to effect a favorable shift of equilibrium, a concept frequently used in a number of patent specifications, is required in the method of the invention. Furthermore, the said high content of components in the concentrated form of the catalyst provides favorable technical conditions or a fast and efficient homogenization of the insoluble components of the catalyst and facilitates favorable chemical changes, thus enabling formation of the catalyst in a macroscopically homogeneous form.

The method to manufacture the alkoxylenation catalyst according to the invention and the efficiency of its application in the light of state-of-the-art methods will now be illustrated by way of examples. Examples I - VII are embodiments of the method to manufacture the ethoxylenation catalyst by the method of the invention; the effects of its application in the process of ethoxylenation are also shown. For comparison, shown in Examples VIII - XII are the results of ethoxylenation processes effected with the use of catalysts having similar compositions, though prepared by state-of-the-art methods. Examples XIII- XVIII provide the compositions of catalysts obtained by the method of the invention.

Example I

The charging container of a colloid mill with operating capacity of 6 dm³ is filled with 3.6 kg of isopropanol, 1.1 kg of calcium acetate monohydrate and 0.275 kg of sulfuric acid. The material is mixed vigorously at ambient temperature to fully homogenize the material contained in the colloid mill. After several minutes the catalyst is obtained as a concentrate in the form of a visually homogeneous, milky suspension. The usefulness of the resulting catalyst is verified in the ethoxylenation reaction, which is carried out in the following manner:

A 2-dm³ stainless steel reactor is filled with 300 g (1 mole) of a methyl ester of rape seed oil acids and 3.7 g of the resulting catalyst concentrate. The concentration of calcium, introduced with the catalyst concentrate, is 0.06 % relative to the methyl ester of rape seed oil acids added (which contains more than 90% of C-iβ fraction). The reactor is then tightly closed and the material contained therein is heated to 403 K, while drying the feed by purging with nitrogen for 30 minutes. On completion of the drying step, the material contained in the reactor is heated to 438 K and ethylene oxide is added. After a short initiation step, the reaction proceeds undisturbed, with good yield. Having added the planned amount, 440 g (10 moles) of ethylene oxide, the product is kept at the reaction temperature for 60 more minutes, whereupon the material contained in the reactor is cooled down to 323 K, blown with nitrogen and discharged. The average conversion rate of ethylene oxide is 4.1 mole per mole of ester per hour. The resulting ethoxylenation product with a narrow homolog distribution has a fractional composition as shown in Table 1.

Example II .

The charging container of a colloid mill with operating capacity of 6 dm³ is filled with 1.125 kg of isopropanol, 2.5 kg of coconut alcohol having C12 -C14 fractions, 1.1 kg of calcium lactate and 0.275 kg of sulfuric acid. The material is mixed vigorously at ambient temperature to fully homogenize the material contained in the colloid mill. After several minutes the catalyst is obtained as a concentrate in the form of a visually homogeneous, thick suspension. The usefulness of the resulting catalyst is verified in the ethoxylenation reaction:

A 2-dm³ stainless steel reactor is filled with 300 g of coconut alcohol having C12 -C14 fractions, and 4.8 g of the catalyst concentrate. Consequently, the concentration of calcium is 0.06 % relative to the C12 -C14 fractions of alcohol added. The reactor is then tightly closed and the material contained therein is heated to 403 K, while drying the feed by purging with nitrogen for 30 minutes. On completion of the drying step, the material contained in the reactor is heated to 438 K and ethylene oxide is added. After a short initiation step, the reaction proceeds undisturbed, with good yield. Having added the planned amount, 660 g of ethylene oxide, the product is kept at the reaction temperature for 60 more minutes, whereupon the material contained in the reactor is cooled down to 323 K, blown with nitrogen and discharged. The average conversion rate of ethylene oxide is 5.46 mole per mole of alcohol per hour. The resulting ethoxylation product with a narrow homolog distribution has a fractional composition as shown in Table 1.

Example III

The container of a laboratory homogenizer is filled with 50.0 g of the mixture of C12 -C14 fraction alcohols being ethoxylenated, 22.5 g of isopropanol, 22 g of calcium acetate monohydrate and 5.5 g of sulfuric acid. The material is mixed vigorously at 303 K to fully homogenize the components. After several minutes the catalyst is obtained as a concentrate in the form of a visually homogeneous, thick suspension. A synthesis is carried out with the use of the resulting catalyst, as described in Example II, except that 2.43 g of the resulting concentrate is added to 300 g of the mixture of C12 -C14 fraction alcohols. Consequently, the concentration of calcium is 0.01 % relative to the C12 -C14 fraction of alcohols added. 670 g of ethylene oxide at an average rate of 4.23 mole per mole of alcohol per hour is added during the synthesis reaction.

Example IV

The container of a laboratory homogenizer is filled with 15.8 g of isopropanol, 65 g of methyl ester of rape seed oil acids subjected to ethoxylenation, 15.4 g of calcium acetate monohydrate and 3.8 g of sulfuric acid. The material is mixed vigorously at ambient temperature to fully homogenize the components. After several minutes the catalyst is obtained as a concentrate in the form of a visually homogeneous, thick suspension.

The usefulness of the resulting catalyst was verified in the ethoxylenation reaction.

The synthesis of ethoxylates is carried out as described in Example I, except that 4.8 g of the resulting concentrate is added to 300 g of methyl ester of rape seed oil acids. Consequently, the concentration of calcium is 0.01 % relative to the methyl esters added. 660 g of ethylene oxide at an average rate of 3,98 mole per mole of ester per hour is added during the synthesis reaction.

Example V

The container of a laboratory homogenizer is filled with 90.0 g of isopropanol, 8.0 g of calcium acetate monohydrate and 2.0 g of sulfuric acid. The material is mixed vigorously at 303 K to fully homogenize the components. After several minutes the catalyst is obtained as a concentrate in the form of a visually homogeneous, thick suspension.

The synthesis of ethoxylates is carried out as described in Example I, except that 7.4 g of the resulting concentrate is added to 300 g of methyl ester of rape seed oil acids. Consequently, the concentration of calcium is 0.01 % relative to the methyl esters added. 440 g of ethylene oxide at an average rate of 3.98 mole per mole of ester per hour is added during the synthesis reaction.

Example VI

The container of a laboratory homogenizer is filled with 35.0 g of the mixture of C12 -C14 fraction alcohols being ethoxylenated, 54 g of calcium acetate monohydrate and 13.0 g of sulfuric acid. After mixing the material in the homogenizer for several minutes at 308 K to fully homogenize the components, the catalyst is obtained as a concentrate in the form of a visually homogeneous paste.

An ethoxylate synthesis reaction is carried out in the presence of the resulting catalyst, as described in Example II, except that 0.81 g of the resulting catalyst concentrate is added to 300 g of the mixture of C12 — C14 fraction alcohols. Consequently, the concentration of calcium is 0.03 % relative to the C12 τCi4 fraction of alcohols added. 440 g of ethylene oxide at an average rate of 4.54 mole per mole of alcohol per hour is added during the synthesis reaction.

Example VII

The container of a laboratory homogenizer is filled with 80.0 g of butanol, 16.0 g of calcium acetate monohydrate and 4.0 g of sulfuric acid. After mixing the material in the homogenizer for severalminutes to fully homogenize the components, the catalyst is obtained as a concentrate in the form of a visually homogeneous, milky suspension.

An ethoxylation reaction with the use of the resulting catalyst is conducted as in Example II, except that 15.0 g of the catalyst is added to 300 g of n-butanol.

Consequently, the concentration of calcium is 0.17 % relative to the n-butanol added.

900 g of a mixture of ethylene oxide and propylene oxide in a ratio of 1:1 by weight is added in ethoxylenation Step I, effected at 110°C. In Step II, 714 g of the mixture of ethylene oxide and propylene oxide in a ratio of 1:1 by weight is added to 300 g of the product of Step I of the synthesis process, yielding a product with an average polyaddition degree of 15.1 mole of a mixture of alkylene oxide per 1 mole of butanol, with an average rate of conversion of the mixture of ethylene oxide and propylene oxide of 3.01 mole per mole of alcohol per hour.

Comparative Example VIII

For comparison, the ethoxylation reaction is carried out as in Example I except that the catalyst in similar concentrations is added in the form of separate active ingredients that may result from a reaction of sulfuric acid with calcium acetate in the making of the catalyst concentrate, directly to the material being subjected to ethoxylenation:

0.74 g of calcium acetate monohydrate and 0.47 g of calcium sulfate is added to 300 g of rape seed oil acid methyl esters. The concentration of calcium is 0.1 % relative to the quantity of methyl esters added. Merely 83 g of ethylene oxide is added within 5 hrs which corresponds to an average conversion rate of ethylene oxide of 0.38 mole per mole of ester per hour.

The synthesis process was terminated as the system showed lack of practically any catalytic activity, although the concentration of calcium used in this Example was much higher than in Examples I - VI. Comparative Example IX

For comparison, the ethoxylenation reaction is carried out as in Example II except that calcium sulfate is the catalyst, and is added directly to the alcohol being subjected to ethoxylenation: 0.27 g of calcium sulfate is added to 300 g of C12 -C14 fraction alcohols. Consequently, the concentration of calcium is 0.026 % relative to the C12 -CM fraction of alcohols added. 660 g of ethylene oxide at an average rate of 0.49 mole per mole of alcohol per hour is added during the synthesis reaction.

In the concentration under study, calcium sulfate showed little activity, not enough to be of practical importance, even though calcium was at a concentration comparable to Examples lll-IV.

Comparative Example X

For comparison, the ethoxylenation reaction is carried out as in Example II except that calcium acetate monohydrate is the catalyst, and is added directly to the alcohol being subjected to ethoxylenation:

0.42 g of calcium acetate monohydrate is added to 300 g of fraction C12 -C14 alcohol. Concentration of calcium relative to fraction C12 -CM alcohol is 0.032%. 660 g of ethylene oxide at an average rate of 1.12 mole per mole of alcohol per hour is added during the synthesis. In the concentration under study, calcium acetate showed more than three times as low catalytic activity as did the catalyst used in Examples I -VI. Moreover, the homolog distribution in the resulting product is relatively broad, compared with that of products made in the presence of the catalyst obtained by the method of the invention (Table 1).

Comparative Example XI

For comparison, the ethoxylenation reaction is carried out as in Example II except that calcium acetate monohydrate and calcium sulfate are used as the catalyst, and are added directly to the alcohol being subjected to ethoxylenation:

0.42 g of calcium acetate monohydrate and 0.27 g of calcium sulfate is added to 300 g of fraction C12 -CM alcohol. A total concentration of calcium relative to fraction C12 -CM alcohol is 0.058%. 660 g of ethylene oxide at an average rate of 1.62 mole per mole of alcohol per hour is added during the synthesis. Even though the concentration of calcium was relatively high, the catalyst showed 2.5 times as low catalytic activity as did the catalyst used in Examples I -VI.

Comparative Example XII

For comparison, the ethoxylenation reaction is carried out as in Example II except that calcium acetate monohydrate and sulfuric acid are used as the catalyst, and are added directly to the alcohol being subjected to ethoxylenation:

1.2 g of calcium acetate monohydrate and 0.6 g of sulfuric acid is added to 300 g of fraction C12 -CM alcohol. The concentration of calcium relative to fraction C12 -CM alcohol is 0.091%. 264 g of ethylene oxide at an average rate of 1.28 mole per mole of alcohol per hour is added during the synthesis.

Even though the components of the catalyst were used at a relatively high concentration, the average conversion rate of ethylene oxide was about 3 times as low as the one in Examples I -VI.

Example XIII

The ethoxylenation catalyst in the form of a homogeneous, milky suspension contains 72.5 % by weight of isopropanol, 22.0 % by weight of calcium acetate monohydrate and 5,5 % by weight of sulfuric acid, or products of their reciprocal reactions, being formed on homogenization.

Example XIV

The ethoxylenation catalyst in the form of a thick, homogeneous suspension contains 22.5 % by weight of isopropanol, 50 % by weight of a mixture of fraction C12 -CM alcohols, 22 % by weight of calcium lactate and 5,5 % by weight of sulfuric acid, products of their reciprocal reactions, being formed on homogenization.

Example XV

The ethoxylenation catalyst in the form of a thick, homogeneous suspension contains 15.4 % by weight of calcium acetate monohydrate, 3,8 % by weight of sulfuric acid, 15.8 % by weight of isopropanol and 65 % by weight of methyl ester of rape seed oil acids, or products of their reciprocal reactions, being formed on homogenization.

Example XVI

The ethoxylenation catalyst in the form of a thick, homogeneous suspension contains 8.0 % by weight of calcium acetate monohydrate, 2.0 % by weight of sulfuric acid and 90 % by weight of isopropanol, or products of their reciprocal reactions, being formed on homogenization.

Example XVII

The ethoxylenation catalyst in the form of a thick, homogeneous suspension contains 52.0 % by weight of calcium acetate monohydrate, 13.0 % by weight of sulfuric acid and 35 % by weight of a mixture of C12 -CM alcohols, or products of their reciprocal reactions, being formed on homogenization.

Table 1 Fractional compositions of ethoxylation products in Examples I, II and X.

the number denotes the quantity of oxyethylene groups attached to an alcohol or ester molecule, for example R/3 denotes an ethoxylate having 3 oxyethylene groups.

Claims

Claims:

1. An alkoxylenation catalyst, being in the form of a visually homogeneous, liquid suspension or a homogeneous paste and containing:

- calcium salts of low molecular carboxylic and/or hydroxycarboxylic acids and/or hydrates of the former,

- a strong oxy-acid, preferably sulfuric acid,

- an alcohol and/or an ester, or products of their reciprocal reactions, being formed on homogenization, a total concentration of the calcium salts and sulfuric acid being from 10% to 65% by weight.

2. A catalyst as claimed in claim 1 , containing calcium acetate and/or calcium lactate and/or hydrates of the former.

3. A catalyst as claimed in claim 1, containing the same alcohol and/or ester that is subjected to ethoxylenation.

4. A method to obtain an alkoxylenation catalyst, wherein a calcium salt of a low molecular carboxylic and/or hydroxycarboxylic acid and/or hydrates of the former (I), are mixed with a strong oxy-acid, preferably sulfuric acid (II), and an alcohol and/or ester (III) at a temperature in the range 283-368 K, the components (I) and (II) at concentrations in the range from 10% to 65% by weight, as well as their proportions, temperatures, time and intensity of mixing being so selected as to obtain a product in the form of a visually homogeneous, liquid suspension or a visually homogeneous paste, for use as a catalyst in the process of alkoxylenation.

5. A method as claimed in claim 4, wherein calcium acetate and/or calcium lactate and/or hydrates of the former are used as the calcium salt.

6. A method as claimed in claim 4, wherein the alcohol and/or ester used are the same as those subjected to ethoxylenation.