WO2013046132A1 - Process for the preparation of dialkyl carbonate compounds - Google Patents

Process for the preparation of dialkyl carbonate compounds Download PDF

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Publication number
WO2013046132A1
WO2013046132A1 PCT/IB2012/055124 IB2012055124W WO2013046132A1 WO 2013046132 A1 WO2013046132 A1 WO 2013046132A1 IB 2012055124 W IB2012055124 W IB 2012055124W WO 2013046132 A1 WO2013046132 A1 WO 2013046132A1
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process according
comprised
reaction
carbon atoms
carbonate
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PCT/IB2012/055124
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French (fr)
Inventor
Alberto Renato DE ANGELIS
Caterina Rizzo
Giulio ASSANELLI
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Eni S.P.A
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Publication of WO2013046132A1 publication Critical patent/WO2013046132A1/en

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    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C68/00—Preparation of esters of carbonic or haloformic acids
    • C07C68/06—Preparation of esters of carbonic or haloformic acids from organic carbonates
    • C07C68/065—Preparation of esters of carbonic or haloformic acids from organic carbonates from alkylene carbonates
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
    • B01J23/007—Mixed salts
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J27/00—Catalysts comprising the elements or compounds of halogens, sulfur, selenium, tellurium, phosphorus or nitrogen; Catalysts comprising carbon compounds
    • B01J27/20—Carbon compounds
    • B01J27/232—Carbonates
    • B01J27/236—Hydroxy carbonates
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07D—HETEROCYCLIC COMPOUNDS
    • C07D317/00—Heterocyclic compounds containing five-membered rings having two oxygen atoms as the only ring hetero atoms
    • C07D317/08—Heterocyclic compounds containing five-membered rings having two oxygen atoms as the only ring hetero atoms having the hetero atoms in positions 1 and 3
    • C07D317/10—Heterocyclic compounds containing five-membered rings having two oxygen atoms as the only ring hetero atoms having the hetero atoms in positions 1 and 3 not condensed with other rings
    • C07D317/32—Heterocyclic compounds containing five-membered rings having two oxygen atoms as the only ring hetero atoms having the hetero atoms in positions 1 and 3 not condensed with other rings with hetero atoms or with carbon atoms having three bonds to hetero atoms with at the most one bond to halogen, e.g. ester or nitrile radicals, directly attached to ring carbon atoms
    • C07D317/34—Oxygen atoms
    • C07D317/36—Alkylene carbonates; Substituted alkylene carbonates
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07D—HETEROCYCLIC COMPOUNDS
    • C07D317/00—Heterocyclic compounds containing five-membered rings having two oxygen atoms as the only ring hetero atoms
    • C07D317/08—Heterocyclic compounds containing five-membered rings having two oxygen atoms as the only ring hetero atoms having the hetero atoms in positions 1 and 3
    • C07D317/10—Heterocyclic compounds containing five-membered rings having two oxygen atoms as the only ring hetero atoms having the hetero atoms in positions 1 and 3 not condensed with other rings
    • C07D317/32—Heterocyclic compounds containing five-membered rings having two oxygen atoms as the only ring hetero atoms having the hetero atoms in positions 1 and 3 not condensed with other rings with hetero atoms or with carbon atoms having three bonds to hetero atoms with at the most one bond to halogen, e.g. ester or nitrile radicals, directly attached to ring carbon atoms
    • C07D317/34—Oxygen atoms
    • C07D317/36—Alkylene carbonates; Substituted alkylene carbonates
    • C07D317/38—Ethylene carbonate

Definitions

  • the present invention relates to a process for the preparation of dialkyl carbonate compounds which can be advantageously used as additives of a biological origin in fuels such as diesel or gasolines.
  • Dialkyl carbonates and in particular diethyl carbonate, can be used as additives for said fuels, increasing the aliquot of product of a biological origin in the fuel and thus reducing the particulate.
  • the Applicant has now found a new method for the preparation of dialkyl carbonate compounds, using a heterogeneous catalyst based on hydrotalcite , obtaining extremely high product yields, higher than 95% molar, at the same time avoiding the formation of toxic and carcinogenic by-products.
  • the present invention therefore relates to a process for the preparation of dialkyl carbonate compounds starting from urea and reagents selected from ethylene glycol, propylene glycol and linear alcohols having a number of carbon atoms ranging from 1 to 20. Said process comprises the following steps:
  • An object of the present invention relates to a process for the preparation of dialkyl carbonate compounds starting from urea and reagents selected from ethylene glycol, propylene glycol and linear alcohols having a number of carbon atoms ranging from 1 to 20. Said process comprises two steps:
  • the intermediate products formed in step (a) are, for example, ethylene carbonate or propylene carbonate.
  • the end-products obtained with the process, object of the present invention are dialkyl carbonates.
  • Preferred products are diethyl carbonate and dibutyl carbonate.
  • the linear alcohols having a number of carbon atoms ranging from 1 to 20 can preferably be of biological origin and even more preferably can be obtained starting from fatty acids with a number of carbon atoms in the chain ranging from 16 to 22.
  • the end-products obtained with the process, object of the present invention can be used as biological component in both gasoline and diesel fuel, allowing a saving of hydrogen in the refinery, which on the other hand, is required for the production of other fuels of a biological nature such as HVO.
  • the catalysts used in the process, object of the present invention, in both steps, are in heterogeneous phase, preferably in solid phase.
  • the catalyst used in step (a) of the process described and claimed in the present text can be any hydrotalcite having the formula:
  • M 11 is a bivalent metal selected from Mg, Fe 11 , Ni 11 , Zn, Cd, Co 11 and mixture thereof
  • M 111 is a trivalent metal selected from Al, Fe 111 , Ga 111 , Cr 111 , Mn 111 , Co 111 and mixtures thereof
  • X is an anion selected from CC>3 2 ⁇ , OH ⁇ and NO 3 ""
  • n is an integer ranging from 0 to 6
  • a is an integer ranging from 4 to 6.
  • the reaction step (a) is carried out at temperatures ranging from 100°C to 150°C and pressures ranging from 2 atm to 0.01 atm.
  • the reaction is preferably carried out at a pressure lower than atmospheric pressure and even more preferably at pressures ranging from 0.05 atm to 0.01 atm.
  • the conversion of the limiting agent (urea) is total and the selectivity to the desired product >95% molar.
  • the aliphatic alcohol is preferably of a biological origin, in the text indicated as bioalcohol, and can be obtained either by fermentation of a biomass or molasses, or by the reduction of a fatty acid, acids that normally have an extremely high number of carbon atoms, for example up to 22 carbon atoms.
  • the aliphatic alcohol of a biological origin may preferably have up to 22 carbon atoms in the chain and more preferably the aliphatic alcohol obtained can have from 1 to 6 carbon atoms.
  • ethanol and butanol are particularly preferred.
  • the catalyst used in step (b) of the process described and claimed in the present text can be a hydrotalcite having the formula:
  • M II 6M III 2 (OH) ⁇ ⁇ 3 ⁇ 40 II 6M III 2 (OH) ⁇ ⁇ 3 ⁇ 40 (II) wherein M 11 is a bivalent metal selected from: Mg, Fe 11 , Ni 11 , Zn, Cd, Co 11 and mixtures thereof.; M 111 is a trivalent metal selected from Al, Fe 111 , Ga 111 , Cr 111 , Mn 111 , Co 111 and mixtures thereof, and X is an anion selected from C0 3 2 ⁇ , OH " and N0 3 " .
  • hydrotalcites wherein M 11 is Zn or Mg, or mixtures of the two, and M 111 is selected from Al, Fe and Cr, M 111 is more preferably Al .
  • the reaction step (b) is carried out at temperatures ranging from 80°C to 130°C, with pressures ranging from 1 atm to 15 atm.
  • the reaction step (b) is carried out using alcohol in excess with respect to the stoichiometric with molar ratios alcohol/ (alkenyl carbonate) ranging from 2.5/1 to 10/1, more preferably from 4/1 to 8/1.
  • the reaction reaches thermodynamic equilibrium with a quantitative selectivity to dialkyl carbonate .
  • the catalysts of step (a) and step (b) can be preferably the same, but can also have a different chemical composition.
  • M 11 is preferably Zn and M 111 is Al .
  • Step (a) of the synthesis of diethylene carbonate with hydrotalcite Zn-Al-N0 3 Step (a) of the synthesis of diethylene carbonate with hydrotalcite Zn-Al-N0 3 .
  • Step (b) of the synthesis of diethylene carbonate with hydrotalcite Zn-Al-NQ 3 Step (b) of the synthesis of diethylene carbonate with hydrotalcite Zn-Al-NQ 3 .
  • Step (a) of the synthesis of diethylene carbonate with hydrotalcite Zn-Al-C0 3 Step (a) of the synthesis of diethylene carbonate with hydrotalcite Zn-Al-C0 3 .
  • Step (b) of the synthesis of diethylene carbonate with hydrotalcite Zn-Al-CQ 3 Step (b) of the synthesis of diethylene carbonate with hydrotalcite Zn-Al-CQ 3 .
  • Step (a) of the synthesis of diethylene carbonate with hydrotalcite Zn-Fe-CQ 3 Step (a) of the synthesis of diethylene carbonate with hydrotalcite Zn-Fe-CQ 3 .
  • Step (b) of the synthesis of diethylene carbonate with hydrotalcite Zn-Fe-CQ 3 Ethylene carbonate, produced according to Example 5, and ethanol are charged into a glass reactor in a molar ratio of 1/4; the hydrotalcite
  • Step (a) of the synthesis of diethylene carbonate with hydrotalcite Zn-Cr-CC>3 Step (a) of the synthesis of diethylene carbonate with hydrotalcite Zn-Cr-CC>3 .
  • Step (b) of the synthesis of diethylene carbonate with hydrotalcite Zn-Cr-C0 3 Step (b) of the synthesis of diethylene carbonate with hydrotalcite Zn-Cr-C0 3 .
  • Ethylene carbonate, produced according to Example 5, and ethanol are charged into a glass reactor in a molar ratio of 1/4; the hydrotalcite Zn 6 Cr 2 (OH) i 6 C0 3 ⁇ 2 ⁇ , synthesized by the Applicant, is then added in a ratio of 5% by weight; the reaction mixture is heated to 83°C and is sent to reflux for 3 hours. After 3 hours, the reaction is interrupted and the reaction product is analyzed by means of gaschromatography . The conversion of . ethylene carbonate proves to be equal to 80% (thermodynamic limit of the transesterification reaction) with a selectivity to the desired product (diethyl carbonate) equal to 97%.
  • reaction intermediate 2-hydroxyethylcarbonate
  • metals Zn, Cr
  • Urea and ethylene glycol are charged into a glass reactor in a molar ratio of 1/1.2 and the hydrotalcite PURAL MG 70, a commercial product with a molar ratio Mg/Al of 7/3, is added in a ratio of 5% by weight; the reaction mixture is heated to 130°C and a vacuum is applied reducing the pressure to 30 mbar. After 3 hours, the reaction is interrupted and the reaction product is analyzed by means of gaschromatography . The conversion of urea proves to be total with a selectivity to the desired product (ethylene carbonate) equal to 18%.
  • the by-products consist of oxazolidone (62%), the corresponding hydroxycarbonate (15%) and ethylene urea (5%) .
  • Step (b) of the synthesis of diethylene carbonate with hydrotalcite EXM 2221 Step (b) of the synthesis of diethylene carbonate with hydrotalcite EXM 2221.
  • Ethylene carbonate, produced according to comparative Example 1, and ethanol are charged into a glass reactor in a molar ratio of 1/4; the commercial hydrotalcite EXM 2221, magnesium and aluminium hydrotalcite with an unknown chemical composition, is then added in a ratio of 5% by weight; the reaction mixture is heated to 83°C and is sent to reflux for 3 hours. After 4 hours, the reaction is interrupted and the reaction product is analyzed by means of gaschromatography.

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  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • External Artificial Organs (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)

Abstract

The present invention relates to a process for the preparation of dialkyl carbonate compounds starting from urea and reagents selected from ethylene glycol and propylene glycol. Said process comprises the following steps: • carrying out a glycolysis reaction, in the presence of a first catalyst in heterogeneous phase, between urea and a reagent selected from ethylene glycol, propylene glycol and linear alcohols with a number of carbon atoms in the chain ranging from 1 to 20, so as to form an alkenyl carbonate; • carrying out a transesterification reaction, in the presence of a second catalyst in heterogeneous phase, between the alkenyl carbonate thus obtained and an aliphatic alcohol having a number of carbon atoms within the range of 1-22, so as to form dialkyl carbonate compounds.

Description

PROCESS FOR THE PREPARATION OF DIALKYL CARBONATE COMPOUNDS
The present invention relates to a process for the preparation of dialkyl carbonate compounds which can be advantageously used as additives of a biological origin in fuels such as diesel or gasolines.
The legislation in force, and even more so in the years to come, envisages that a part of the fuels used, such as diesel and gasoline, contain a component of a biological origin. Dialkyl carbonates, and in particular diethyl carbonate, can be used as additives for said fuels, increasing the aliquot of product of a biological origin in the fuel and thus reducing the particulate.
The synthesis of diethyl carbonate is described in the Mistubishi patents EP 0638541, US 6,031,122 and EP 0625519, wherein urea reacts directly with ethanol, using a catalyst in homogeneous phase (catalysts based on metal oxides, in particular ZnO, and acetates), at a temperature ranging from 150°C to 190°C. The yields obtained are lower than 80% as main by-product in the relative carbamate, which is a toxic and highly carcinogenic substance. Triazines, which are also toxic and mutagenic, are also obtained as further by- products.
The Applicant has now found a new method for the preparation of dialkyl carbonate compounds, using a heterogeneous catalyst based on hydrotalcite , obtaining extremely high product yields, higher than 95% molar, at the same time avoiding the formation of toxic and carcinogenic by-products.
The present invention therefore relates to a process for the preparation of dialkyl carbonate compounds starting from urea and reagents selected from ethylene glycol, propylene glycol and linear alcohols having a number of carbon atoms ranging from 1 to 20. Said process comprises the following steps:
• carrying out a glycolysis reaction, in the presence of a first catalyst in heterogeneous phase based on hydrotalcite , between urea and a reagent selected from ethylene glycol, propylene glycol and .linear alcohols with a number of carbon atoms in the chain ranging from 1 to 20, so as to form an alkenyl carbonate ;
• carrying out a transesterification reaction, in the presence of a second catalyst in heterogeneous phase based on hydrotalcite, between the alkenyl carbonate thus obtained and an aliphatic alcohol having a number of carbon atoms within the range of 1-22, so as to form dialkyl carbonate compounds.
The use of a catalyst in heterogeneous phase allows the end-product to be easily separated without additional costs contrary to what occurs with processes of the known art which use catalysts in homogeneous phase .
The use of a catalyst in heterogeneous phase also allows an end-product to be obtained, in which metals dissolved in a significant quantity are not present. Detailed description
An object of the present invention .therefore relates to a process for the preparation of dialkyl carbonate compounds starting from urea and reagents selected from ethylene glycol, propylene glycol and linear alcohols having a number of carbon atoms ranging from 1 to 20. Said process comprises two steps:
• carrying out a glycolysis reaction, in the presence of a first catalyst in heterogeneous phase, between urea and a reagent selected from ethylene glycol, propylene glycol and linear alcohols with a number of carbon atoms in the chain ranging from 1 to 20, preferably ethylene glycol, so as to form an alkenyl carbonate;
• carrying out a transesterification reaction, in the presence of a second catalyst in heterogeneous phase, between the alkenyl carbonate thus obtained and an aliphatic alcohol having a number of carbon atoms within the range of 1-22, preferably within the range of 1-6, even more preferably ethyl or butyl alcohol, so as to form dialkyl carbonate compounds .
The intermediate products formed in step (a) are, for example, ethylene carbonate or propylene carbonate.
The end-products obtained with the process, object of the present invention, are dialkyl carbonates. Preferred products are diethyl carbonate and dibutyl carbonate.
The use of the end-products, dialkyl carbonates, (obtained with the process of the present invention) as additives for diesel or gasolines, has various advantages .
The linear alcohols having a number of carbon atoms ranging from 1 to 20 can preferably be of biological origin and even more preferably can be obtained starting from fatty acids with a number of carbon atoms in the chain ranging from 16 to 22.
First of all, the use of a biological component obtained via fermentation as additive in diesel fuel represents an alternative to biocomponents obtained from vegetable oils (FAME or Fatty Acid Methyl Ester, HVO or Hydrogenated Vegetable Oil) . Secondly, the possibility of using alcohols in the formulation of fuels for diesel (such as Diethyl carbonate DEC), allows the imbalance currently existing in Europe between the demand and offer profile of gasoline/diesel fuel, to be partially rebalanced.
The end-products obtained with the process, object of the present invention, can be used as biological component in both gasoline and diesel fuel, allowing a saving of hydrogen in the refinery, which on the other hand, is required for the production of other fuels of a biological nature such as HVO.
Finally, the synthesis process from urea for the production of dialkyl carbonates uses C02 for the production of urea, with the consequent recovery of aliquots of CO2 according to the Kioto protocol.
The catalysts used in the process, object of the present invention, in both steps, are in heterogeneous phase, preferably in solid phase.
The catalyst used in step (a) of the process described and claimed in the present text, can be any hydrotalcite having the formula:
M^aM11^ (OH) 16X ·ηΗ20 (I) wherein M11 is a bivalent metal selected from Mg, Fe11, Ni11, Zn, Cd, Co11 and mixture thereof; M111 is a trivalent metal selected from Al, Fe111, Ga111, Cr111, Mn111, Co111 and mixtures thereof, X is an anion selected from CC>32~, OH~ and NO3 "", n is an integer ranging from 0 to 6, a is an integer ranging from 4 to 6.
Hydrotalcites in which M11 is magnesium or zinc and 111 is aluminium, iron or chromium are preferred; among these, hydrotalcites even more preferred are those in which "a" is 6 and the anion X is C03 2", N03 " or OH.
The reaction step (a) is carried out at temperatures ranging from 100°C to 150°C and pressures ranging from 2 atm to 0.01 atm. The reaction is preferably carried out at a pressure lower than atmospheric pressure and even more preferably at pressures ranging from 0.05 atm to 0.01 atm.
Under these conditions, the conversion of the limiting agent (urea) is total and the selectivity to the desired product >95% molar.
The aliphatic alcohol is preferably of a biological origin, in the text indicated as bioalcohol, and can be obtained either by fermentation of a biomass or molasses, or by the reduction of a fatty acid, acids that normally have an extremely high number of carbon atoms, for example up to 22 carbon atoms. The aliphatic alcohol of a biological origin may preferably have up to 22 carbon atoms in the chain and more preferably the aliphatic alcohol obtained can have from 1 to 6 carbon atoms. Among these aliphatic alcohols ethanol and butanol are particularly preferred.
The catalyst used in step (b) of the process described and claimed in the present text, can be a hydrotalcite having the formula:
MII6MIII2 (OH) ΐβΧ ·η¾0 (II) wherein M11 is a bivalent metal selected from: Mg, Fe11, Ni11, Zn, Cd, Co11 and mixtures thereof.; M111 is a trivalent metal selected from Al, Fe111, Ga111, Cr111, Mn111, Co111 and mixtures thereof, and X is an anion selected from C03 2~, OH" and N03 " .
Particularly preferred are hydrotalcites wherein M11 is Zn or Mg, or mixtures of the two, and M111 is selected from Al, Fe and Cr, M111 is more preferably Al . Hydrotalcites wherein M11 is Zn or Mg and M111 is selected from Al, Fe and Cr, "a" is 6 and X is CO3 ", are more preferred.
The reaction step (b) is carried out at temperatures ranging from 80°C to 130°C, with pressures ranging from 1 atm to 15 atm. The reaction step (b) is carried out using alcohol in excess with respect to the stoichiometric with molar ratios alcohol/ (alkenyl carbonate) ranging from 2.5/1 to 10/1, more preferably from 4/1 to 8/1. The reaction reaches thermodynamic equilibrium with a quantitative selectivity to dialkyl carbonate .
The catalysts of step (a) and step (b) can be preferably the same, but can also have a different chemical composition. When the catalyst is the same in both steps, then M11 is preferably Zn and M111 is Al .
In the end-product, obtained with the process described and claimed above, there are no metals dissolved in a significant quantity due to the fact that the catalyst used in both steps is in heterogeneous form, and is preferably a solid. In particular, metals such as Zn, Mg and Cu are present in a quantity lower than 0.05 ppm.
This factor is extremely important as the presence of metals in the end-product causes fouling in the fuel injectors, in particular in common rail diesel engines.
The same products obtained with the processes of the known art, on the other hand, have a much higher metal content, and in the order of percent as the catalyst used (for example ZnO) is partially soluble in the reaction mixture. Consequently the dialkyl carbonates obtained with the conventional processes cannot be used as additives for diesel or gasolines, as only one ppm of Zn is sufficient in the diesel for significantly fouling the injectors.
Example 1
Step (a) of the synthesis of diethylene carbonate with hydrotalcite Zn-Al-N03.
Urea and ethylene glycol are charged into a glass reactor in a molar ratio of 1/1.2 and the hydrotalcite ΖηεΑΐ2 (OH) 16 O3 ·ηΗ20, synthesized by the Applicant, is added in a ratio of 5% by weight; the reaction mixture is heated to 130°C and a vacuum is applied reducing the pressure to 30 mbar. After 3 hours, the reaction is interrupted and the reaction product is analyzed by means of gaschromatography . The conversion of urea proves to be total with a selectivity to the desired product (ethylene carbonate) equal to 95%. The by- products consist of oxazolidone (3%) and the corresponding hydroxycarbonate (2%) .
Example 2
Step (b) of the synthesis of diethylene carbonate with hydrotalcite Zn-Al-NQ3.
Ethylene carbonate, produced according to Example
1, and ethanol are charged into a glass reactor in a molar ratio of 1/4; the hydrotalcite
Zn6Al2 (OH) i6N03 ·ηΗ20, synthesized by the Applicant, is then added in a ratio of 5% by weight; the reaction mixture is heated to 83°C and is sent to reflux for 3 hours. After 3 hours, the reaction is interrupted and the reaction product is analyzed by means of ■gaschromatography. The conversion of ethylene carbonate proves to be equal to 80% (thermodynamic limit of the transesterification reaction) with a selectivity to the desired product (diethyl carbonate) higher than 99%. N'o significant quantities of by-products are- observed. A quantitative analysis on the reaction product thus obtained excludes the presence of metals (Zn, g) up to the analytical limit analyzable (0.5 ppm) .
Example 3
Step (a) of the synthesis of diethylene carbonate with hydrotalcite Zn-Al-C03.
Urea and ethylene glycol are charged into a glass reactor in a molar ratio of 1/1.2 and the hydrotalcite Zn6Al2 (OH) 16CO3 ■ 6¾0, synthesized by the Applicant, is added in a ratio of 5% by weight; the reaction mixture is heated to 130°C and a vacuum is applied reducing the pressure to 30 mbar. After 3 hours, the reaction is interrupted and the reaction product is analyzed by means of gaschromatography . The conversion of urea proves to be total with a selectivity to the desired product (ethylene carbonate) equal to 96%. The by- products consist of oxazolidone (3%) and the corresponding hydroxycarbonate (1%) .
Example 4
Step (b) of the synthesis of diethylene carbonate with hydrotalcite Zn-Al-CQ3.
Ethylene carbonate, produced according to Example
3, and ethanol are charged into a glass reactor in a molar ratio of 1/4; the hydrotalcite Zn6Al2 (OH) 16 O3 · 6 H2O, synthesized by the Applicant, is then added in a ratio of 5% by weight; the reaction mixture is heated to 83°C and is sent to reflux for 3 hours. After 3 hours, the reaction is interrupted and the reaction product is analyzed by means of gaschromatography. The conversion of ethylene carbonate proves to be equal to 80% (thermodynamic limit of the transesterification reaction) with a selectivity to the desired product (diethyl carbonate) higher than 99%. No significant quantities of by-products are observed. A quantitative analysis on the reaction product thus obtained excludes the presence of metals (Zn, Mg) up to the analytical limit analyzable (0.5 ppm) .
Example 5
Step (a) of the synthesis of diethylene carbonate with hydrotalcite Cu-Zn-Al-CQ3.
Urea and ethylene glycol are charged into a glass reactor in a molar ratio of 1/1.2 and the hydrotalcite Cu Zn2Al2 (OH) 16C03 ·ηΗ20, synthesized by the Applicant, is added in a ratio of 5% by weight; the reaction mixture is heated to 130°C and a vacuum is applied reducing the pressure to 30 mbar. After 10 hours, the reaction is interrupted and the reaction product is analyzed by means- of gaschromatography . The conversion of urea proves to be total with a selectivity to the desired product (ethylene carbonate) equal to 90%. The byproducts consist of oxazolidone (4%) and the corresponding hydroxycarbonate (6%) .
Step (b) of the synthesis of diethylene carbonate with hydrotalcite Cu-Zn-Al-CQ3.
Ethylene carbonate, produced according to Example 5, and ethanol are charged into a glass reactor in a molar ratio of 1/4; the hydrotalcite
Cu4Zn2Al2 (OH) 16CO3 ·ηΗ20, synthesized by the Applicant, is then added in a ratio of 5% by weight; the reaction mixture is heated to 83°C and is sent to reflux for 3 hours. After 3 hours, the reaction is interrupted and the reaction product is analyzed by means of gaschromatography . The conversion of ethylene carbonate proves to be equal to 80% (thermodynamic limit of the transesterification reaction) with a selectivity to the desired product (diethyl carbonate) equal to 98%. No significant quantities of by-products are observed, the only product present with the desired product is the reaction intermediate ( 2 -hydroxyethylcarbonate ) . A quantitative analysis on the reaction product thus obtained excludes the presence of metals (Zn, Cu) up to the analytical limit analyzable (0.5 ppm) .
Example 6
Step (a) of the synthesis of diethylene carbonate with hydrotalcite Zn-Fe-CQ3.
Urea and ethylene glycol are charged into a glass reactor in a molar ratio of 1/1.2 and the hydrotalcite Zn6Fe2 (OH) 16CO3 ·ηΗ20, synthesized by the Applicant, is added in a ratio of 5% by weight; the reaction mixture is heated to 130°C and a vacuum is applied reducing the pressure to 30 mbar. After 7 hours, the reaction is interrupted and the reaction product is analyzed by means of gaschromatography. The conversion of urea proves to be total with a selectivity to the desired product (ethylene carbonate) equal to 92%. The byproducts consist of oxazolidone (3%) and the corresponding hydroxycarbonate (4%) .
Step (b) of the synthesis of diethylene carbonate with hydrotalcite Zn-Fe-CQ3. Ethylene carbonate, produced according to Example 5, and ethanol are charged into a glass reactor in a molar ratio of 1/4; the hydrotalcite
Zn6Fe2 (OH) i6C03 ·ηΗ2θ, synthesized by the Applicant, is then added in a ratio of 5% by weight; the reaction mixture is heated to 83°C and is sent to reflux for 3 hours. After 3 hours, the reaction is interrupted and the reaction product is analyzed by means of gaschromatography . The conversion of ethylene carbonate proves to be equal to 80% (thermodynamic limit of the transesterification reaction) with a selectivity to the desired product (diethyl carbonate) equal to 99%. No significant quantities of by-products are observed, the only product present with the desired product is the reaction intermediate (2-hydroxyethylcarbonate) . A quantitative analysis on the reaction product thus obtained excludes the presence of metals (Zn, Fe) up to the analytical limit analyzable (0.5 ppm) .
Example 7
Step (a) of the synthesis of diethylene carbonate with hydrotalcite Zn-Cr-CC>3 .
Urea and ethylene glycol are charged into a glass reactor in a molar ratio of 1/1.2 and the hydrotalcite Zn6Cr2 (OH) ieC03 ·ηΗ20, synthesized by -the Applicant, is added in a ratio of 5% by weight; the reaction mixture is heated to 130°C and a vacuum is applied reducing the pressure to 30 mbar. After 6 hours, the reaction is interrupted and the reaction product is analyzed by means of gaschromatography. The conversion of urea proves to be total with a selectivity to the desired product (ethylene carbonate) equal to 91%. The byproducts consist. of oxazolidone (4%) and the corresponding hydroxycarbonate (5%) .
Step (b) of the synthesis of diethylene carbonate with hydrotalcite Zn-Cr-C03.
Ethylene carbonate, produced according to Example 5, and ethanol are charged into a glass reactor in a molar ratio of 1/4; the hydrotalcite Zn6Cr2 (OH) i6C03 ·ηΗ2θ, synthesized by the Applicant, is then added in a ratio of 5% by weight; the reaction mixture is heated to 83°C and is sent to reflux for 3 hours. After 3 hours, the reaction is interrupted and the reaction product is analyzed by means of gaschromatography . The conversion of .ethylene carbonate proves to be equal to 80% (thermodynamic limit of the transesterification reaction) with a selectivity to the desired product (diethyl carbonate) equal to 97%. No significant quantities of by-products are observed, the only product present with the desired product is the reaction intermediate ( 2-hydroxyethylcarbonate ) . A quantitative analysis on the reaction product thus obtained excludes the presence of metals (Zn, Cr) up to the analytical limit analyzable (0.5 ppm) .
Comparative Example 1
Step (a) of the synthesis of diethylene carbonate with hydrotalcite PURAL MG 70.
Urea and ethylene glycol are charged into a glass reactor in a molar ratio of 1/1.2 and the hydrotalcite PURAL MG 70, a commercial product with a molar ratio Mg/Al of 7/3, is added in a ratio of 5% by weight; the reaction mixture is heated to 130°C and a vacuum is applied reducing the pressure to 30 mbar. After 3 hours, the reaction is interrupted and the reaction product is analyzed by means of gaschromatography . The conversion of urea proves to be total with a selectivity to the desired product (ethylene carbonate) equal to 18%. The by-products consist of oxazolidone (62%), the corresponding hydroxycarbonate (15%) and ethylene urea (5%) .
Comparative Example 2
Step (b) of the synthesis of diethylene carbonate with hydrotalcite EXM 2221.
Ethylene carbonate, produced according to comparative Example 1, and ethanol are charged into a glass reactor in a molar ratio of 1/4; the commercial hydrotalcite EXM 2221, magnesium and aluminium hydrotalcite with an unknown chemical composition, is then added in a ratio of 5% by weight; the reaction mixture is heated to 83°C and is sent to reflux for 3 hours. After 4 hours, the reaction is interrupted and the reaction product is analyzed by means of gaschromatography. The conversion of ethylene carbonate proves to be equal to 7.3% (thermodynamic limit of the transesterification reaction) with a selectivity to the desired product (diethyl carbonate) equal to 48%, whereas 52% of the reaction product consists of .the partial transesterification product (ethyl-2 hydroxyethyl carbonate) .

Claims

A process for the preparation of dialkyl carbonates compounds starting from urea and from reagents selected from ethylene glycol, propylene glycol and linear alcohols having a number of carbon atoms comprised from 1 and 20, said process comprising the steps:
■ carrying out a glycolysis reaction, in the presence of a first catalyst in heterogeneous phase, between urea and a reagent selected from ethylene glycol, propylene glycol and linear alcohols with a number of carbon atoms in the chain comprised from 1 and 20, so as to form an alkenyl carbonate;
■ carrying out a transesterification reaction, in the presence of a second catalyst in heterogeneous phase, between .the alkenyl carbonate so obtained and an aliphatic alcohol having a number of carbon atoms comprised in the range 1-22, so as to form the dialkyl carbonates compounds .
The process according to claim 1 wherein the catalyst in the step (a) is a hydrotalcite of formula :
M^aM11^ (OH) 16X ·ηΗ20 (I) wherein M11 is a bivalent metal selected from Mg, Fe11, Ni11, Zn, Cd, Co11 and mixture thereof; M is a trivalent metal selected from Al, Fe111, Ga111, Cr111, Mn111, Co111 and mixture thereof, X is an anion selected from C03 2 , OH~ and NO3 ", n is an integer number comprised from 0 and 6, a is an integer number comprised from 4 and 6.
The process according to claim 1 wherein the catalyst in the step (b) is an hydrotalcite of formula :
Figure imgf000018_0001
wherein M11 is a bivalent metal selected from: Mg, Fe11, Ni11, Zn, Cd, CoI]:and mixture thereof; M111 is a trivalent metal selected from Al, Fe111, Ga111, Cr111, Mn111, Co111 and mixture thereof, and X is an anion comprised from C03 2~ , OH" and N03 " .
The process according to claim 2 wherein M11 is magnesium or zinc and M111 is aluminium.
The process according to claim 4 wherein "a" is
6 and the anion X is C03 2~ N03 " or OH.
The process according to claim 3 wherein M11 is zinc or magnesium, or mixture of the two, and
M111 is selected from Al, Fe and Cr.
The process according to claim 6 wherein M111 is
Al.
The process according to claim 3 wherein M11 is zinc or magnesium and M111 is selected from Al, Fe and Cr, "a" is 6 and X is C03 ~.
The process according to claims 1-8 wherein the aliphatic alcohol is of biologic origin and has a number of carbon atoms up to 22.
10. The process according to claim 9 wherein the aliphatic alcohol has a number of carbon atoms comprised from 1 to 6.
11. The process according to claims 1-8 wherein the aliphatic alcohol is ethanol or butanol .
12. The process according to claims 1-11 wherein the step (a) of the process is carried out at temperatures comprised from 100°C and 150°C and pressures comprised from 2 atm and 0.01 atm.
13. The process according to claims 1-11 wherein the step (b) of the process is carried out at temperatures comprised from 80°C and 130°C, with pressures comprised from 1 atm and 15 atm.
14. The process according to claims 1-11 wherein the aliphatic alcohol is in excess with respect of the stoichiometric with molar ratios alcohol/ (alkenil carbonates) comprised from 2.5/1 and 10/1.
PCT/IB2012/055124 2011-09-28 2012-09-26 Process for the preparation of dialkyl carbonate compounds WO2013046132A1 (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109772286A (en) * 2019-03-06 2019-05-21 中国海洋石油集团有限公司 A kind of solid base catalyst and its preparation method and application

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0344354A (en) * 1989-07-11 1991-02-26 Daicel Chem Ind Ltd Production of dialkyl carbonate
EP0625519A1 (en) 1993-05-19 1994-11-23 Mitsubishi Gas Chemical Company, Inc. Method for the production of alkylene carbonates
EP0638541A1 (en) 1993-08-12 1995-02-15 Mitsubishi Gas Chemical Company, Inc. Process for the production of dialkyl carbonate
US6031122A (en) 1997-03-17 2000-02-29 Mitsubishi Gas Chemical Company, Inc. Process for producing dialkyl carbonate

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0344354A (en) * 1989-07-11 1991-02-26 Daicel Chem Ind Ltd Production of dialkyl carbonate
EP0625519A1 (en) 1993-05-19 1994-11-23 Mitsubishi Gas Chemical Company, Inc. Method for the production of alkylene carbonates
EP0638541A1 (en) 1993-08-12 1995-02-15 Mitsubishi Gas Chemical Company, Inc. Process for the production of dialkyl carbonate
US6031122A (en) 1997-03-17 2000-02-29 Mitsubishi Gas Chemical Company, Inc. Process for producing dialkyl carbonate

Non-Patent Citations (6)

* Cited by examiner, † Cited by third party
Title
DATABASE CA [online] CHEMICAL ABSTRACTS SERVICE, COLUMBUS, OHIO, US; HONDA, KIMIAKI: "Preparation of dialkyl carbonates from alkylene carbonates", XP002675709, retrieved from STN Database accession no. 1991:246810 *
DATABASE CA [online] CHEMICAL ABSTRACTS SERVICE, COLUMBUS, OHIO, US; SHU, TING ET AL: "Synthesis of propylene carbonate from urea and 1,2-propanediol catalyzed by hydrotalcite -like compounds", XP002675711, retrieved from STN Database accession no. 2006:138999 *
MURUGAN, C. ET AL: "Transesterification of propylene carbonate with methanol using Mg-Al-CO3 hydrotalcite as solid base catalyst", INDIAN JOURNAL OF CHEMISTRY, SECTION A: INORGANIC, BIO-INORGANIC, PHYSICAL, THEORETICAL & ANALYTICAL CHEMISTRY , 49A(9), 1182-1188 CODEN: ICACEC; ISSN: 0376-4710, September 2010 (2010-09-01), XP008151759 *
SHU, TING ET AL: "Synthesis of propylene carbonate from urea and 1,2-propanediol catalyzed by hydrotalcite -like compounds", SHIYOU HUAGONG , 35(1), 11-14 CODEN: SHHUE8; ISSN: 1000-8144, 2006 *
WATANABE Y ET AL: "Hydrotalcite-type materials as catalysts for the synthesis of dimethyl carbonate from ethylene carbonate and methanol", MICROPOROUS AND MESOPOROUS MATERIALS, ELSEVIER SCIENCE PUBLISHING, NEW YORK, US, vol. 22, no. 1-3, 17 June 1998 (1998-06-17), pages 399 - 407, XP004128332, ISSN: 1387-1811, DOI: 10.1016/S1387-1811(98)00099-7 *
XIANMEI XIE ET AL: "Synthesis of Propylene Carbonate Catalyzed by Copper-containing Hydrotalcite-like Compounds", MRS PROCEEDINGS, vol. 1279, 2010, XP055026714, ISSN: 0272-9172, DOI: 10.1557/PROC-1279-24 *

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109772286A (en) * 2019-03-06 2019-05-21 中国海洋石油集团有限公司 A kind of solid base catalyst and its preparation method and application

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