NL8104054A - IMPROVED METHOD FOR PREPARING ETHYLENE GLYCOL. - Google Patents

Description

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Improved method for preparing ethylene glycol.

The invention relates to an improved process for the preparation of ethylene glycol.

Due to the decrease in petroleum reserves and rising prices, the emphasis has increasingly shifted to the use of synthesis gas instead of oil as a starting material for the preparation of various chemicals, such as methanol, formaldehyde and ethylene glycol. The advantage of synthesis gas is that it can be prepared from raw materials other than petroleum, such as, for example, natural gas or coal, and in principle from slate oil and tar sand.

An example of an industrial process for the preparation of ethylene glycol, starting from synthesis gas as starting material, is the reaction of formaldehyde with carbon monoxide and water at high pressure (higher than 300 at) in the presence of an acidic catalyst for the preparation of hydroxyacetic acid (glycolic acid ), which is then reacted with methanol to form the methyl ester; the latter is then converted into the glycol by catalytic hydrogenation. See U.S. Patents 2,316,564, 2,153,064, 2,152,852, 2,385,448, and 2,331,094.

Another proposed process using synthesis gas for the preparation of ethylene glycol is the reaction of methanol and carbon monoxide using a rhodium-catalyzed high pressure process; see U.S. Patents 4,155,428 and 4,115,433.

As to the type of process for the preparation of ethylene glycol as described herein, it should be noted that the oxidative dimerization or dehydrodimerization of various organic compounds by peroxides is a very ancient technique developed by the excellent free radical theorist MS Kharasch and his students. These studies became the foundation of much subsequent free radical chemistry. Kharasch et al. In JACS, 65, 15, 1943 describes the 8104054 * i - 2 - * dehydrodimerization of acetic acid to succinic acid with acetyl peroxide in a 50 mol% use selectivity, based on acetyl peroxide, the use selectivity being defined as the number of moles of dehydrodimer product prepared divided by 5 the number of moles of peroxide converted. Isobutyric acid provided tetramethyl-succinic acid in a 42.2 mol% use selectivity. Kharasch et al. In J. Org. Chem. 10, 386, 1945 describes the ester methyl chloroacetate, which is dimerized to dimethyl dichloro succinate by acetyl peroxide in a 42% use selectivity. Kharasch et al.

10 in J. Organ. Chem. 10, 401, 1945 describes the dimerization of cumene and ethylbenzene with acetyl peroxide in 61.9 mol% and 32.1 mol% in their dehydrodimers, respectively. Wiles et al in I, E & C, August 1949, p. 1682, describe the effectiveness of di-tert-butyl peroxide and 2,2-di- (tert-butyl peroxy) butane for the dimerization of 15 cumene to 1.1 2,2-tetramethyl-1,2-diphenylmethane. The benzoate ester of benzyl alcohol was dimerized to the benzoate ester of the corresponding glycol, diphenylene glycol, with di-tert-butyl peroxide by Rust et al., J.A.C.S., 70, 3258 (1948).

The literature is full of many other examples describing the preparation of dehydrodimers in very low concentrations with a use selectivity of generally 20-50 mole percent based on the peroxide consumed. Such selectivities are generally too low for a method intended for industrial development.

25 With regard to ethylene glycol, two approaches based on reactions initiated by peroxide should be mentioned:

The first is described in Schwetlick et al., Angew. Chem. 71, 1960, no. 21, pp. 779 and 780, and is based on it.

Heating a mixture of di-tert-butyl peroxide and methanol in a molar ratio of 1:20 in an autoclave and / or under reflux for 10 hours at 140 ° C. An ethylene glycol yield of 26% is reported, noting that increasing the alcohol excess increases the yield.

The second and more important reaction pathway to ethylene-8104054 * * -3-glycol, in its importance with respect to the invention, is described by Oyama in J. Org. Chem., July 30, 1965, pp. 2429-2432, Oyama particularly describes the reaction of 9 moles of methanol, 1.8 moles of 15% aqueous formaldehyde and 0.45 moles. tert-5 butyl peroxide (di-tert-butyl peroxide) for 12 hours at 140 ° C, yielding 0.21 mol of ethylene glycol (Table I at the top of the right column on page 2430), directly under Table I Note: "The yield of ethylene glycol in the reaction of formaldehyde with methanol is higher than that of tert-butyl peroxide caused by dimerization of methanol.

This fact suggests that hydroxymethyl radical (D) couples to formaldehyde. "Oyama describes in more detail how this reaction was carried out and the products obtained, and contrasts the dehydrodimerization of methanol in the presence of tert-butyl-15 peroxide and in the absence of formaldehyde, in the experimental section beginning on page 2431 (in particular, the chapters entitled "Reaction of Methanol with Formaldehyde" and "Dimerization of Methanol" on page 2432).

The yields of ethylene glycol obtained by Oyama are relatively small. Oyama's only run with methanol - based on the reaction of methanol, aqueous formaldehyde and tert-butyl peroxide described above at 140 ° C for 12 hours - yielded only 1.86 wt% ethylene glycol.

The reaction described above can be led to a higher yield of ethylene glycol by significantly reducing the amount of organic peroxide used relative to the amounts of formaldehyde and methanol present, compared to what Oyama uses. In addition, increasing the amount of methanol and decreasing the amount of water over the other components of the reaction mixture over the amounts used by Oyama has also been found to contribute to providing a higher yield of ethylene glycol. For example, heating a mixture of 78.5 wt% methanol, 1.5 wt% di-tert-butyl peroxide, 6.9 wt% formaldehyde, and 13.1 wt% water for 2 hours at 155 ° C, a yield of 8104054-4 - __________________ __________________________________________________ __ _____.% Of 4.5 wt.% Ethylene glycol in the product mixture. This corresponds to a yield of about 7.1 moles of ethylene glycol per mole of di-tert-butyl peroxide used (Oyama obtained 0.466 moles of ethylene glycol per mole of di-tert-butyl peroxide in its reaction). This improvement is described in more detail in US patent application

Series no.183,537 of September 2, 1980.

According to the process of the invention, the preparation of a small amount of methylal by-product in ethylene glycol, formed from methanol and an organic peroxide, alone or in the presence of formaldehyde and water, is obtained by adding a basic material to the reactants in an amount which is sufficient to reduce the amount of hydrogen ions formed during the reaction without unduly decreasing ethylene glycol formation due to by-product formation.

We have now found that in the preparation of ethylene glycol from methanol and an organic peroxide, especially in the presence of formaldehyde and water, acids, such as formic acid, are formed during the reaction, which form the formation of methylal from methanol and catalyze formaldehyde. It is highly desirable to minimize the formation of methylal in order to avoid unnecessarily large and expensive distillation equipment required for the purification of the ethylene glycol product. We have now found that when a basic material is added to the reactants in a minor amount to reduce the amount of hydrogen ions formed by the acid formation, the amount of methylal by-product is significantly reduced. The amounts of basic material added to the reactants can be as high as the amount needed to neutralize all or part of the acid formed to prevent it from catalyzing the reaction of methanol and formaldehyde to form methylal. When too much basic material is added to the reactants, the formaldehyde formed or added can be converted into formose sugars, which are clearly visible due to the burmum color and characteristic odor of the reaction mixture and the low detectability of formaldehyde in the process When too much basic material is added, very small amounts of ethylene glycol are formed.

The term "basic material" is used in this text to refer to any materials that suppress the amount of hydrogen ions formed in the form of acids during the reaction. Suitable basic materials are the hydroxides of alkali metals such as lithium, sodium, potassium, rubidium or cesium or alkaline earth metals such as calcium, strontium, barium, beryllium or magnesium. Also included in the term "basic material" are salts of alkali or alkaline earth metals and weakly ionizable acids, such as oxalic, tartaric, malic, citric, formic, lactic, acetic, carbonic, phosphoric, pyrophosphoric, pyrophosphoric, propionic, butyric and the like. Of particular interest for the purposes of the invention are the sodium and potassium salts of weakly ionizable acids, such as acetic acid, formic acid, oxalic acid, carbonic acid (including the bicarbonates) and phosphoric acid. Examples of these sodium and potassium-20 salts are sodium acetate, potassium acetate, sodium bicarbonate, potassium bicarbonate, sodium formate, potassium formate, sodium oxalate, potassium oxalate, sodium carbonate, potassium carbonate, sodium pyrophosphate, sodium phosphate, potassium phosphate, potassium phosphate. The amount of sodium or potassium salt of a weakly ionized acid added to the reaction participants can be 50-3500 ppm, preferably 100-30Qppm and most preferably 100-1500 ppm of the original reaction mixture. In the case of other basic materials, the amount should be equivalent to the amount reported for sodium and potassium-30 salts of weakly ionized acids, taking into account their ability to neutralize hydrogen ions in the present system. When a metal hydroxide, such as sodium hydroxide or potassium hydroxide, is used as the basic material, the amount added is no greater than would be necessary to neutralize the acids formed during the reaction. For example, the use of sodium 8104054 <* é - 6 - hydroxide in an amount of 25-60 ppm of the total reaction product resulted in the preparation of satisfactory amounts of ethylene glycol and reduced amounts of methylal, compared to a reaction mixture containing no basic materials 5 contains. In addition to the basic materials described above, it is also possible to use zinc oxide, basic aluminum oxide, various basic thorium compounds and generally any basic material which reduces the amount of hydrogen ions formed from the formed acids without disturbing the reaction.

For the purposes of the invention, an amount of at least 0.25 wt% and up to 25 wt% organic peroxide, based on the weight of the reaction mixture, can be used for the preparation of ethylene glycol from methanol, formaldehyde, organic peroxide and water, although generally reaction feeds used in the practice of the invention are no more than about 6 wt%, for example 0.25-6 wt%, and preferably no more than about 3 wt% %, for example 0.75-3% by weight of organic peroxide. In most cases, the feed also contains 45-97 wt%, preferably 80-85 wt% methanol and 0.5-13 wt%, preferably 2-12 wt% formaldehyde and 0.5-35 wt%, preferably 2-10 wt% water.

This reaction is generally carried out at a temperature of 100-200 ° C, preferably 125-175 ° C with a residence time of no more than 8 hours, usually 0.25-8 hours and preferably 0.5-4 hour. Generally, the reaction time required to bring the reaction to the desired degree of completion is the shorter the higher the temperature. The pressure at which the reaction is carried out is little or not critical. Pressures from 2 autogenous pressures up to about 42 kg / cm can be used.

For the reaction of methanol with an organic peroxide in the absence of water and formaldehyde, the amount of methanol in the reaction feed is 70-95 wt.%, Preferably 75-90 wt.%. Accordingly, the amount of organic peroxide in the reaction feed is 5-35% by weight, and preferably 10-25% by weight. The reaction is carried out at a temperature in the 8104054-7 range of 100-200 ° C, preferably 155-180 ° C. The reaction time is no more than 8 hours, preferably 0.5-4 hours. The yield of ethylene glycol is 2-8% by weight of the total reaction products.

The organic peroxide used in the process of the invention satisfies the formula R-O-O-R 1, wherein R and R 1 are each independently an alkyl or aralkyl group having 3-12 carbon atoms. Organic peroxides which can be used are, for example, di-tert-butyl peroxide, dicumyl peroxide, t-butyl cumyl peroxide and t-butyl ethyl benzyl peroxide. The preferred organic peroxide is di-tert-butyl peroxide.

The reactions can be carried out batchwise, filling a reactor, such as a stirred autoclave, with the original reaction mixture, which is then reacted, after which the entire reaction mixture is discharged and purified semi-continuously, alternating the original reaction mixture. and product mixture is withdrawn from the reactor, or continuously, the reaction mixture being continuously supplied and product mixture being continuously withdrawn from the reactor. The product mixture can then be purified using conventional techniques such as distillation or solvent extraction to obtain ethylene glycol of the desired purity, preferably fiber quality, as well as by-products such as tert-butanol, methyl formate, glycerol, acetone and optionally methylal. formed during the process despite the addition of basic material of the invention.

The examples below serve to illustrate the invention.

Examples I-XXI

Fills of the different feed compositions containing methanol (MeOH), di-tert-butyl peroxide (DtBP), formaldehyde (C ^ O) as a mixture of 36% wt CH2 O containing 14% wt MeOH and 50% water (H 2 O) contains, sodium bicarbonate (NaHCO 2), except for Examples XIII and XIV, in which no basic material was added, and optionally additional water in the 8104054 - 8 ί * + fill that is not present in the added formaldehyde solution, were prepared and filled in a 304 SS Hoke reactor at atmospheric pressure. The reactor was sealed and placed in a thermostatically controlled oil bath maintained at the stated reaction temperature and allowed to react at the indicated reaction temperature for the indicated reaction time at autogenous pressure. After the reaction time had elapsed, the reactor was cooled by dilution, venting, draining, and analyzed by gas chromatography for ethylene glycol (EG) and methylal present.

The results of these examples are set forth in Table A which shows the composition of the original charge, the temperature and the reaction time used for the reaction, as well as the amount of ethylene glycol formed in each example, expressed both as weight percent of the reaction mixture and Based on mole of each product per mole of di-tert-butyl peroxide consumed in the reaction.

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However, the stability of DtBP is such that any recovered DtBP could be recycled.

As can be seen from the data in Table A, when sodium bicarbonate is added to the reactants as compared to Examples XIII and XIV, in which no sodium bicarbonate was added, the process produces smaller amounts of methylal.

In Comparative Examples XIII and XIV, a trace of sodium bicarbonate may be present in the reaction mixture due to the fact that the monomeric aqueous formaldehyde for the reactions was formed from paraformaldehyde. Therefore, a small amount of hydrochloric acid was added to depolymerize the paraformaldehyde into aqueous monomer formaldehyde. After the aqueous monomer was formed, a small amount of sodium bicarbonate was used to neutralize the solution using the color change of litmus paper to determine the neutralization. This may have led to the presence of a trace of sodium carbonate in Examples XIII and XIV, in which no additional sodium bicarbonate was added, whereby the amount of methylal formed in these examples may be slightly reduced. Although the traces of sodium bicarbonate possibly present in Example XIII and Example XIV must have been much less than the 0.013% by weight added in Examples VII and VIII, the fact that they have led to some reduction in the methylal formation have contributed to narrowing the differences between the methylal formed in Examples XIII and XIV, in which no bicarbonate was added, and formed in the remaining examples, in which bicarbonate was added in different amounts, like example VIII. Regardless of this factor, however, the result of Example VIII, as well as that of the other examples in which bicarbonate was added, shows that smaller amounts of methylal are formed when higher amounts of sodium bicarbonate are used compared to the comparative examples XIII and XIV.

A starting reaction mixture containing methanol (MeOH), 5 di-tert-butyl peroxide (DtBP), formaldehyde (CH20) and water (H20) and as basic material sodium bicarbonate (NaHCO4), sodium acetate (NaOAc) or sodium formate (NaPo) ( except Example XXII, in which no basic material was used) was placed in a stainless steel bomb, which was sealed and heated under autogenous pressure. The formaldehyde used was in a mixture of 55% by weight formaldehyde, 35% by weight methanol, 10% by weight water and 25ppm sodium hydroxide. To obtain the 5 wt% water content of the reactants, the formaldehyde mixture was diluted with methanol or water as needed to obtain the desired proportions. After the stated reaction time, the product mixture was removed from the bomb and analyzed for ethylene glycol (EG) and other products, such as methylal (MeAl).

The results of these examples are set forth in Table B, where the composition of the original fill, the temperature, the reaction time used for the reaction, the amount of ethylene glycol formed in each example, both in weight percent of the product mixture and product EG per moles of di-tert-butyl peroxide consumed in the reaction are reported. Methylal by-product formed is reported in% by weight of the product mixture. It should be noted that in Example XXII, the only example in this table which does not contain a basic material, a significantly smaller amount of the by-product methylal was formed than in the other examples.

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An original reaction mixture containing methanol (MeOHJ, di-tert-butyl peroxide (DtBP), formaldehyde (CE ^ O), water (H2OJ and in some cases (examples XLI-LV) sodium bicarbonate (NaHCO ^)) was filled in a stainless steel steel bomb which was sealed and heated under autogenous pressure The formaldehyde used in these examples contained a mixture of 55% by weight formaldehyde, 35% by weight methanol and 10% by weight water To distinguish from the formaldehyde used in Examples XXII-10 XXXVII, no sodium hydroxide was present in this formaldehyde mixture To obtain the 5 wt% water content of the reactants, the formaldehyde mixture was diluted with methanol or water as needed to obtain the correct proportions. for the prescribed reaction time, the product mixture 15 was removed from the bomb and analyzed for ethylene glycol (EG) and methylal (MeAl).

The results of these examples are shown in Table C, in which the composition of the original fill, the temperature, the reaction time used for the reaction and the amount of ethylene glycol formed in each example, both expressed in weight percent of the product mixture (under products % by weight) as stated in moles of ethylene glycol per mole of di-tert-butyl peroxide consumed during the reaction. Methylal by-product formed is reported in% by weight of the product mixture. It should be noted that when the sodium bicarbonate is increased from 50 to 1500 ppm in the reaction mixture, less by-product methylal is formed.

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Example LVI-LXX

An original reaction mixture containing methanol (MeOH), di-tert-butyl peroxide (DtBP), formaldehyde (C CO), water and some buffer or not, was autoclaved (300 cm) in a stainless steel (316 SS) ^). All examples were run at 155 ° C under autogenous pressure for 2 hours. All fillings were stirred during the reaction except in Examples LVIII and LIX. After the prescribed reaction time, the product mixture was removed from the bomb and analyzed for ethylene glycol (EG), formaldehyde (CH2 O) and methylal (MeAl). The different basic materials used are identified as follows: NaOH (sodium hydroxide), NaFo (sodium formate), HFo (formic acid), H ^ PO ^ (phosphoric acid), Na ^ P20 ^ .10 ^ O (pyrophosphate), and NaHCO ^ (sodium bicarbonate ). The combination of phosphoric acid and sodium hydroxide in example LXVI provides sodium phosphate. The combination of oxalic acid and sodium hydroxide in Example LXIX provides sodium oxalate.

The results of these examples are set forth in Table D, in which the composition of the original fill, the temperature, the reaction time used for the reaction, basic materials and the amount of ethylene glycol formed in each example, both expressed in weight percent of the product mixture moles of ethylene glycol per mole of di-tert-butyl peroxide consumed in the reaction are reported. The other products that occur in the reaction product mixture are formaldehyde and methylal. Table D shows that using different basic materials, the amount of ethylene glycol formed can be maintained at a satisfactory level, forming a small amount of methylal by-product. When no basic material was used, larger amounts of methylal were formed. As for Examples LXIV and LXV, in which 5000 ppm sodium formate was added, small yields of ethylene glycol were obtained to form small amounts of methylal. Sodium formate (Examples LXI-LXIII) which was used as the basic material in an amount of 1000 ppm yielded a 8104054 * 16-16% satisfactory amount of ethylene glycol and a small amount of methylal. Example LXX, using sodium carbonate in an amount of 150 ppm, provided a satisfactory amount of ethylene glycol, but the amount of methylal formed was slightly higher than in other runs using the same amount of sodium bicarbonate as reported in Table C. The cause of this difference is not clear and we assume that the result of the test is an anomaly. Sodium pyrophosphate (example LXVII-LXVIII) and sodium oxalate (example LXIX) used as the basic material also provided satisfactory amounts of ethylene glycol and small amounts of methylal. Addition of 60 ppm of sodium hydroxide (examples LVIII-LX) provided satisfactory amounts of ethylene glycol and reduced amounts of methylal as compared to the results obtained without sodium hydroxide or any other basic material. The results of the above examples indicate that satisfactory amounts of ethylene glycol can be formed from methanol and formaldehyde and the simultaneous formation of methylal can be kept low when a basic material is used in accordance with the invention.

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An original reaction mixture containing methanol (MeQH), di-tert-butyl peroxide (DtBP), formaldehyde (C 1 O 2), water and 5 or some basic material, was charged in 3 a stainless steel (316 SS) autoclave (300 cm}. The reaction was carried out at a temperature of 154-156 ° C with a reaction time in the range of 0.75-2 hours under autogenous pressure. All tests were stirred. After the prescribed reaction time, the product was -10 mixture removed from autoclave and analyzed for ethylene glycol (EG) and methylal (MeAl) The materials used as basic materials are identified as NaOH (sodium hydroxide) and NaHCO 2 (sodium bicarbonate).

In the examples LXXI-LXXIV, in which no basic materials were present, large amounts of methylal are formed. In the examples LXXV-LXXVI, in which small amounts of sodium hydroxide were used, the amount of methylal formed was considerably less than in the examples LXXI-LXXIV, but higher than in the examples LXXVII-LXXIX, in which sodium bicarbonate was used. Although Example LXXIX, using 0.42 wt% (4200 ppm) sodium bicarbonate, lowered the methylal content, a very small amount of ethylene glycol was formed. There are indications that in this test a large part of the formaldehyde was converted into formose sugars because of the burmum color, the characteristic odor and very little presence of formaldehyde.

The results of these examples are set forth in Table E, which lists the composition of the original charge, the temperature, the reaction time used in the reaction, and the amounts of ethylene glycol and methylal 30 formed in each example.

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These examples demonstrate the use of other basic materials to reduce methylal formation in the ethylene glycol process. An original reaction mixture containing methanol (MeOH), di-tert-butyl peroxide (DtBP), formaldehyde (C 10 O), water (H 2 O) and the basic material was charged in a glass reactor, which in this case existed from a sealed serum vial. The vial was placed in a tube reactor filled with methanol and sealed. It was then placed in a thermostatically controlled oil bath held at 155 ° C and the reaction was allowed to proceed at autogenous pressure for 2 hours. After the prescribed reaction time, the product mixture was removed from the glass reactor and analyzed for ethylene glycol (EG) and methylal (MeAl). The results of these examples are set forth in Table F, 15 which lists the composition of the original fill and the amounts of ethylene glycol and methylal formed. The basic materials used in the examples were zinc oxide (ZnO), bismuth oxide (Bi2C> 2), cerium oxide (Ce20), tin (IV) oxide (SnO2) thorium oxide (ThC ^), aluminum oxide (A ^ O ^) and sodium bicarbonate { NaHCO.j) for comparison purposes.

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The results are given in Examples LXXX-LXXXV, in which a feed stream of 87.25 wt% methanol, 2.0 wt% di-tert-butyl peroxide, 10.0 wt% formaldehyde and 0.75 wt% water was used , demonstrate the improvement in lower methylal 5 formation obtained using zinc oxide as the basic material. Thus, significantly lower amounts of methylal were obtained in the examples LXXX1V and LXXXV using zinc oxide compared to the examples LXXX-LXXXII in which no basic material was used. Also, Examples LXXXIV and LXXXV produced smaller amounts of methylal than Example LXXXIII using 0.005 wt% sodium bicarbonate.

Examples LXXXVIII-XCIII show the use of metal oxides as the basic material using a feed stream consisting of 92.55 wt% methanol, 1.0 wt% di-tert-butyl peroxide, 6.0 wt. % formaldehyde and 0.45 wt% water. For example, zinc oxide (example LXXXVIII), bismuth oxide (example LXXXIX), thorium oxide (example XCII) and aluminum oxide (example XCIII) all yielded smaller amounts of methylal compared to the comparative examples LXXXVI and LXXXVII, in which no basic material was used. The use of bismuth oxide (example LXXXIX) and cerium oxide (example XC) yielded slightly smaller amounts of methylal than comparative examples LXXXVI and LXXXVII, but not as low as was obtained with the other metal oxides as the basic material in this series of examples.

Examples XCIII-C

These examples demonstrate the effective use of sodium bicarbonate as the basic material when added in portions of the reactants.

An original reaction mixture, containing methanol (MeOH), a di-tert-butyl peroxide (DtBP), formaldehyde (CH 2 O), water and sodium bicarbonate (NaHCO 2), was charged into a 304 stainless steel Hoke reactor at atmospheric pressure. The reactor is sealed and placed in a thermostatically controlled oil bath maintained at 155 ° C and allowed to react at autogenous pressure for 1 hour. After the first hour of the reaction, additional reactants, designated as the second step, were added and the reaction proceeded for an additional 1 hour. Additional reactants were added in the same manner as the second stage addition to give additional stages as indicated in Table G, in which the total amounts of reactants are indicated for the different addition stages. After the last addition of reactants and completion of the reaction (which is believed to be 1 hour after addition of the last 10 reactants), the reactor was cooled by dilution, venting, draining and the contents analyzed by gas chromatography on ethylene glycol (EC ) and other products.

The results of these examples are set forth in Table G, which indicated the composition of the reactants charged to the reactor containing methanol in the various steps. The amounts of the reactants used are reported as% by weight of the total reactants. The amounts of ethylene glycol and methylal, as noted, are reported as% by weight of the total reaction products.

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Claims (22)

A process for the preparation of ethylene glycol by reacting methanol with an organic peroxide of the formula ROO-Rj, wherein R and R19 are each independently an alkyl or aralkyl-5 group having 3-12 carbon atoms, characterized in that adds to the reactants a basic material in an amount sufficient to decrease the amount of hydrogen ions formed during the reaction without unduly reducing the ethylene glycol formation by byproduct formation. 2. Process according to claim 1, characterized in that the basic material is added in an amount sufficient to significantly reduce the amount of methylal formed compared to the result obtained if no basic material is present and the amount of the The basic material is less than the amount in which formose sugars are formed in substantial amounts, as evidenced by the amber color and characteristic odor of the formose sugar. 3. Process according to claim 1 or 2, characterized in that the basic material is a metal hydroxide, in which the metal is an alkaline earth metal or an alkali metal, or a salt of such a metal hydroxide and a weakly ionized acid. 4. Process according to claim 3, characterized in that the basic material used is sodium hydroxide, potassium hydroxide or a sodium or potassium salt of a weakly ionized acid, the anion of that acid consisting of acetate, formate, oxalate, carbonate, bicarbonate or phosphate. 5. Process according to claim 4, characterized in that the basic material used is sodium acetate, potassium acetate, sodium bicarbonate, potassium bicarbonate, sodium formate, potassium formate, sodium oxalate, potassium oxalate, sodium phosphate, potassium phosphate, sodium pyrophosphate or potassium pyrophosphate. from 50-3500 ppm, based on the total reaction mixture. 8104054 - 26 -_ <i> 4, V W * - * r. Process according to claim 5, characterized in that 100-3000 ppm of basic material is used, based on the total reaction mixture and is digested as organic peroxide. butyl peroxide. Process according to claim 6, characterized in that 100-1500 ppm basic material is used, based on the total reaction mixture. 8. A process for the preparation of ethylene glycol by reaction of methanol, an organic peroxide and formaldehyde in the presence of water, the organic peroxide satisfying the formula ROOR ^, wherein R and R ^ each independently an alkyl or aralkyl group having 3-12 carbon atoms, characterized in that a basic material is added to the reaction mixture in an amount sufficient to reduce the amount of hydrogen ions formed during the reaction without the formation of ethylene glycol due to by-product formation to be reduced excessively. 9. Process according to claim 8, characterized in that the basic material is used in an amount sufficient to significantly reduce the amount of methylal formed compared to the result obtained when no basic material is present and the amount of this basic material is less than that, with formose sugars being formed in substantial amounts, as evidenced by the burmum color and characteristic odor of the formose sugar. 10. Process according to claim 8 or 9, characterized in that zinc oxide is used as the basic material. 11. Process according to claim 8 or 9, characterized in that the basic material used is an alkali metal or alkaline earth metal hydroxide or a salt of such metal hydroxide and a weakly ionized acid. 12. Process according to claim 11, characterized in that the basic material used is sodium acetate, potassium acetate, sodium bicarbonate, potassium bicarbonate, sodium formate, potassium 8104054 Λ-27 - formate, sodium oxalate, potassium oxalate, sodium pyrophosphate, potassium pyrophosphate or sodium phosphate and 50-3500 ppm of basic material based on the original reaction mixture. Process according to claim 12, characterized in that 100-300 ppm of basic material, based on the total reaction mixture, is used and as organic peroxide di-tert-butyl peroxide. 14. Process according to claim 13, characterized in that 100-1500 ppm basic material, based on the total reaction mixture, is used. 15. Process according to claim 8cf 9, characterized in that an original reaction mixture is used which contains 45-97 wt.% Methanol, 0.25-6 wt.% Di-tert-butyl peroxide, 0.5-13 15 wt.% formaldehyde and 0.5-35 wt.% water, the wt.% being based on the total reaction mixture, and carrying out the reaction at a temperature of 100-200 ° C for a reaction time of 0.25-8 hours . 16. Process according to claim 15, characterized in that 100-1500 ppm sodium bicarbonate, based on the total reaction mixture, is used as the basic material. Process according to claim 15, characterized in that the basic material used is 100-1500 ppm sodium acetate, based on the total reaction mixture. Process according to claim 15, characterized in that 100-1500 ppm sodium formate is used as the basic material, based on the total reaction mixture. 19. Process according to claim 15, characterized in that the basic material used is 100-1500 ppm sodium oxalate, based on the total reaction mixture. 20. Process according to claim 15, characterized in that the basic material used is 100-1500 pp. Sodium phosphate, based on the total reaction mixture. 21. Process according to claim 15, characterized in that the basic material used is 100-3000 ppm sodium pyrophosphate 8104054 V-28-ύ, -y-ν *, based on the total reaction mixture, 22. A process for the preparation of ethylene glycol as described herein. 5 y / 8104054 1 /