PT107637A - PRODUCTION OF FUELS USING MICROBIAL GLYCOLIPIDS WITH LIPIDIC CHAINS COMPOSED FOR 6 TO 14 CARBONES - Google Patents

Abstract

The present invention relates to the process of production of liquid fuel for aviation, land and sea transport from microbial glycolipids with lipidic chains composed of 6 to 14 carbon. This process is characterized by the conversion of microbial glycolipids into a mixture of organic compounds THROUGH CHEMICAL TRANSESTERIFICATION OF GLYCOLIPIDE WITH AN ALCOHOL IN ESTERS WITH 7 TO 16 CARBON AND MIXTURES, OR CONVERSION OF GLYCOLIPHIDE IN HYDROCARBONS WITH 4 TO 14 CARBON. ORGANIC COMPOUNDS OBTAINED BY THESE PROCESSES ARE FOR APPLICATION AS FUEL, AS SUCH, OR IN MIXTURES WITH OTHER SUBSTANCES, FOR AIR, TERRESTRIAL OR NAUTICAL TRANSPORT, INCLUDING BUT NOT LIMITED TO TRANSPORT WITH TEMPERATURES BELOW ZERO GRAUS CELCIUS.

Description

PRODUCTION OF FUELS USING MICROBIAL GLYCOLIPIDS WITH LIPIDIC CHAINS COMPOSED FOR 6 TO 14

CARBONOS

Field of the Invention The present invention relates to the process of producing liquid fuel for air, land and nautical transport from microbial glycolipids with lipid chains composed of 6 to 14 carbons.

This process is characterized by converting microbial glycolipids into a mixture of organic compounds by their chemical transesterification with an alcohol, namely methanol, ethanol, propanol or butanol isopropanol in esters of 7 to 16 carbons and their mixtures, or conversion to hydrocarbons having from 4 to 14 carbons.

The organic compounds obtained by this process may be used as fuel as such or in mixtures with other fuels, resulting in aviation fuels with a freezing point below minus 40 degrees Celsius and a calorific value exceeding 40 Megajoules per kilogram (1,2 ) or in land or nautical transport fuels, in these cases resulting in fuels with freezing points below zero degrees Celcius.

State of the art

Global climate change seemingly associated with increasing greenhouse gas emissions and issues of rising fuel price and safety have resulted in a shift from fossil fuel energy sources to more sustainable and renewable sources. For land transportation, there is an effort to develop alternative energy sources such as bioethanol, biodiesel or the use of electricity to power cars, trucks and rail systems. However, for the aviation industry, the use of such solutions is not possible. The calorific power available from batteries, fuel cells or bioethanol is not enough. Biofuels, such as biodiesel obtained from vegetable or animal oils, have melting points equal to or greater than zero degrees Celsius, such as biodiesel obtained from vegetable or animal oils, and can not be used for aviation (2). 0 " aviation fuel " is a type of specialized fuel derived from petroleum, which requires a freezing point below minus 40 degrees Celsius and a calorific value greater than forty Megajoules per kilogram (1,2), permitting the maintenance of liquid fuel at flight temperatures and providing sufficient energy to maintain adequate flight autonomy and carrying capacity for commercial use. Conventionally, aviation fuels are of fossil origin, kerosene, rich in hydrocarbons having 10 to 16 carbons per molecule, aromatics and naphthenes (1). The specifications for aviation fuels required to ensure their approval in terms of efficiency and safety are summarized in the following table (1).

The processes proposed for production of aviation fuel from biological sources involve a process of formation of synthetic gas from biomass and the liquefaction of this gas through the reaction of Fischer-Tropsch (4), or, alternatively, a catalytic fractionation and hydrogenation of biomass, including vegetable oils or long-chain animal oils, into hydrocarbons of suitable size (5). These are processes involving the breaking of carbon-carbon bonds, being energetically intensive and therefore their efficiency is inherently limited.

Also in land transport in cold climates, such as polar regions (which include a large portion of the United States of America, Canada, Nordic countries and northern Asia), where biodiesel tends to solidify making alternative biofuels are not efficient to replace the fossil fuel.

There is a need in the current state of the art for the development of compositions containing biofuels that do not solidify in low temperature environments and that meet the specifications for use as a fuel for terrestrial or nautical transport at low temperatures and aviation. Fuels that are kept below zero degrees C (classes C, D, E, F according to EN 590) are for the purpose of this invention designated as " Winter Diesel ". Several microbial species have the ability to produce glycolipids consisting of 6 to 14 lipid chains attached to sugars through inherently labile esters (6).

Various methods of chemical transesterification of esters with an alcohol in the respective alcohol ester (7) are described in the literature, in particular using an acid, for example sulfuric acid or a base, for example methoxide and ethoxide or sodium or potassium hydroxide, as catalyst . Transesterification reactions can also be catalyzed by enzymes such as lipases (8).

Taking into account the ease in breaking ester groups, the catalytic reaction of esters with hydrogen results in the formation of hydrocarbons (3). Most of the oils found in animal and plant species are composed of chains of 16 or 18 carbons. Thus, the respective biodiesel, formed from these oils, has a freezing point near zero degrees Celsius, posing problems for its use in land and nautical transport in regions with more severe winters.

The proposed solutions include decreasing the fraction in which this biofuel is mixed with diesel (of fossil origin) or the use of additives. The use of alcohol esters with shorter chains effectively solves this problem (D.

SUMMARY OF THE INVENTION The present invention relates to the liquid fuel production process for aviation, land and nautical transports from microbial glycolipids with lipid chains composed of 6 to 14 carbons. This process is characterized by converting microbial glycolipids into a mixture of organic compounds by their chemical transesterification with an alcohol, to esters with chains of from 7 to 16 carbons and their mixtures, or conversion to hydrocarbons with chains of 4 to 14 carbons. The ester linkage of the glycolipids is broken down by transesterification or catalytic reaction with hydrogen, organic compounds being obtained, such as esters or hydrocarbons, which have a carbon number per molecule of from 7 to 16 and 4 to 14 carbons, respectively.

In one embodiment, the organic compounds obtained from the conversion of the microbial glycolipids, esters with chains of 7 to 16 carbons, or hydrocarbons with chains of 4 to 14 carbons, are used as such for use in winter diesel for transport land transport and nautical transport. The " as such " should be understood in the present invention as a way of using said organic compounds without being in mixtures with fossil fuels.

In another embodiment, the organic compounds obtained from the conversion of the microbial glycolipids, esters with chains of 7 to 16 carbons or hydrocarbons with chains of 4 to 14 carbons, are used in mixtures with fossil fuels for use in fuel for aviation or as winter diesel for terrestrial or nautical transport.

Mixtures of esters with chains of 7 to 16 carbons may be combined up to 20% (v / v) with fossil fuels for use in liquid aviation fuels.

Mixtures of hydrocarbons with chains of 4 to 14 carbons may be combined up to 50% (v / v) with fossil fuels for use in liquid aviation fuels. The fuel obtained has a low freezing point and high calorific value, suitable for use in aviation or inland or nautical transport, at temperatures below zero degrees Celsius.

The present invention relates to the liquid fuel production process for aviation, land and nautical transports from microbial glycolipids with lipid chains composed of 6 to 14 carbons. This process is characterized by converting microbial glycolipids into a mixture of organic compounds by their chemical transesterification with an alcohol, to esters of 7 to 16 carbons and mixtures thereof, or conversion to hydrocarbons having 4 to 14 carbons. The fuel composition of the present invention may be prepared based on microbial glycolipids. The microbial glycolipids used may be obtained from vegetable, animal or microbial oils, lignocellulosic compounds, sugars or alcohols and converted to a composition of hydrocarbons or alcohol esters suitable for use in aviation or low temperature climates. The size of the lipid chains of microbial glycolipids, lower than that found in vegetable oils used for biodiesel production, offers a unique opportunity for the production of fuels capable of combining high calorific value and low freezing point. Examples of glycolipids with 6 to 14 carbon lipid chains are rhamnolipids and mannitolitrite lipids. The ester linkage of the glycolipids is broken down by acidic, basic or enzymatic transesterification processes or by catalytic reaction with hydrogen, with esters having 7 to 16 carbons or hydrocarbons having 6 to 14 carbons respectively being obtained. The fact that the ester linkage is particularly labile makes these reactions energetically facilitated making the process more efficient than those previously proposed, notably Fischer-Tropsch or long chain oil breakage. Ester or hydrocarbon molecules obtained from glycolipids are separated from the sugar fraction and used for the production of a low freezing point fuel composition and high calorific value.

Aviation fuels can be obtained by mixing the ester or hydrocarbon molecules produced from the microbial glycolipids, up to 50% with other aviation-certified fuels, including but not limited to Jet A or Jet Al fuel, resulting in a point fuel of freezing less than 40 degrees Celsius negative and calorific value higher than 40 Megajoules per gauge.

Fuels for inland or nautical transport at preferential, but not exclusively, temperatures below zero degrees Celsius are obtained using the esters and hydrocarbons obtained from the glycolipids as such or in mixtures with, but not limited to, diesel of fossil origin or biological, resulting in a fuel with freezing point below zero degrees Celcius.

In one embodiment, the organic compounds obtained from the conversion of the microbial glycolipids, esters with chains of 7 to 16 carbons or hydrocarbons with chains of 4 to 14 carbons, are used as such as fuel for land transport and nautical transport.

In another embodiment, the organic compounds obtained from the conversion of the microbial glycolipids, esters with chains of 7 to 16 carbons or hydrocarbons with chains of 4 to 14 carbons, are used in mixtures with fossil fuels for aviation fuel or as winter diesel for terrestrial or nautical transport.

Mixtures of esters with chains of 7 to 16 carbons may be combined up to 20% (v / v) with fossil fuels for use in liquid aviation fuels.

Mixtures of hydrocarbons with chains of 4 to 14 carbons may be combined up to 50% (v / v) with fossil fuels for use in liquid aviation fuels. The fuel obtained has a low freezing point and high calorific value, suitable for use in aviation or inland or nautical transport, at temperatures below zero degrees Celsius. The freezing point of hydrocarbons and alkanes is directly proportional to the length of their carbon chains, with the lowest freezing points being obtained for the shorter chains. However, the combustion energy of these molecules decreases with their size. The size of the lipid chains, composed of 6 to 14 carbons, of the microbial glycolipids used for the production of these fuels, is the ideal size for the production of fuels for aviation or winter diesel, meeting the respective specifications.

The lipid moieties and the glycosidic unit of the glycolipid are covalently linked by ester bonds, which are relatively labile, and their breakdown is facilitated in reactional and energetic terms.

Examples

For a better understanding of the invention, examples of the application of the present invention will be described below by way of non-limiting illustration. It is expected that the same product will be obtained in the chemical transesterifications using other examples of alcohol, such as ethanol, butanol, propanol, among others, since for these alcohols the chemical reaction mechanisms are identical, resulting in the group level alcohol and are not significantly affected by the alkyl groups of these molecules.

Example 1

Production of methyl esters with 7 to 15 carbons obtained by alkaline transesterification of glycolipids with lipid chains between 6 and 14 carbons with methanol. 0.5 g of mannichitritol lipids were added to 0.4 g of sodium methoxide in 1 ml of methanol, and heated at 50Â ° C for 6 hours under stirring. The resulting reaction mixture was extracted with water and hexane (1: 1 ratio) at ambient temperature, resulting in the organic phase, a mixture of methanol esters of the composition of 10% methyl octanoate, 45% methyl and 45% methyl dodecanoate. The aqueous phase was discarded. The yield of the reaction was 50-60%. This yield was calculated as the ratio of moles of methanol esters per mole of lipid chains present in the reaction glycolipid where 100% corresponds to a reaction in which the substrate is completely converted.

Example 2

Production of methyl esters with 7 to 15 carbons obtained by acid transesterification of glycolipids with lipid chains between 6 and 14 carbons with methanol. To 0.5 g of

mannitolitrite lipids were added 0.1 mM sulfuric acid in 3 ml methanol, and heated at 80 ° C for 6 hours under stirring. The resulting reaction mixture was subjected to extraction with water and hexane at room temperature, resulting in the organic phase, a mixture of methanol esters with the composition 10% methyl octanoate, 45% methyl decanoate 45% methyl dodecanoate. The aqueous phase was discarded. The yield of the reaction was greater than 95%. This yield was calculated as the ratio of moles of methanol esters per mole of lipid chains present in the reaction glycolipid where 100% corresponds to a reaction in which the substrate is completely converted.

Example 3

Production of hydrocarbons having 7 to 15 carbons obtained by catalytic reaction of glycolipids with lipid chains between 6 and 14 carbons with hydrogen gas. 0.5 g of mannichitritol lipids were placed in a metal vessel along with a catalyst commonly used in the area previously activated by dimethyl sulphide at 350 ° C pressurized at 50 bar for 6 hours. The resulting reaction mixture was extracted with water and hexane at room temperature, resulting in the organic phase in a mixture of alkanes with the composition 10% octane, 45% decane and 45% dodecane. The aqueous phase was discarded. The yield of the reaction was 50-60%. This yield was calculated as the ratio of moles of hydrocarbons per mole of lipid chains present in the glycolipid subjected to the reaction, where 100% corresponds to a reaction in which the substrate is completely converted.

Example 4

Mixtures 10, 20 and 50 and 100% v / v in methyl esters with 7 to 15 carbons with Jet A and quantification of freezing point, calorific value, flash point, viscosity and density of the mixtures. Table 2 provides the properties of the aviation fuel mixtures with the fuel molecules produced by transesterification. With mixtures of esters produced up to 20% with Jet A, freezing temperatures below -40 ° C were obtained, a point of ignition higher than 47 ° C, a calorific value above 44 Megajoules per kilogram. The viscosity values at -20Â ° C obtained were less than 5 cSt and the density, measured at 152Â ° C, within the range of 0.775 to 0.840 kg / m3.

Table 2: Values obtained for different combinations of methyl esters with fossil fuel for aviation.

* Methyl ester blends obtained from the transesterification processes described in example 1.

Example 5

Mixtures 10, 20 and 50 and 100% v / v in hydrocarbons having 4 to 14 carbons with Jet A and quantification of freezing point, density, ignition points, viscosity and calorific value of mixtures. Table 3 provides the properties of the aviation fuel mixtures with the fuel molecules produced catalytic reaction with hydrogen. With blends of hydrocarbons produced up to 50% with Jet A, freezing temperatures below -442 ° C, flash point above 44 ° C, calorific value above 46 MJ / kg were obtained. The viscosity values at -20Â ° C obtained were less than 2.5 cSt and the density, measured at 152Â ° C, within the range of 0.775 to 0.840 kg / m3.

Table 3: Values obtained for different combinations of alkane mixtures with fossil fuel for aviation.

* Alkane mixtures obtained by the hydrogenation processes described in example 2.

Example 6

Mixtures 10, 20, 30, 50 and 100% v / v in methyl esters with 7 to 15 carbons with diesel and quantification of freezing points, calorific value, ignition points, viscosity and density of mixtures. Table 4 provides the properties of fuel blends, commercial gas oil, with the fuel molecules produced by transesterification. With mixtures of esters produced up to 50% with gasoil, freezing temperatures were obtained from -6.2 to -7.82 ° C (mixtures from 10 to 50%). If used at 100%, the ester molecules produced have a freezing point of -20Â ° C.

Table 4: Values obtained for different combinations of mixtures of methyl esters with gas oil.

* Methyl ester blends obtained from the transesterification processes described in example 1.

Example 7

Mixtures 10, 20, 30, 50, and 100% v / v in hydrocarbons having 4 to 14 carbons with diesel and freezing point quantification, calorific value, flash point, viscosity and density of mixtures. Table 5 provides the properties of fuel blends, commercial gas oil, with the fuel molecules produced by catalytic reaction with hydrogen. With blends of hydrocarbons produced up to 50% with gasoil, freezing temperatures of -7.0 to -13.22 ° C (blends of 10 to 50%) were obtained. If used at 100%, the hydrocarbon molecules produced in Example 2 have a freezing point of -30.9 ° C.

Table 5. Values obtained for different mixtures of alkanes with gas oil.

* Alkane mixtures obtained by the hydrogenation processes described in example 2.

References 1. Milton, B. World Jet Fuel Specifications with Avgas

Supplement. (2005) .at http: //www.exxonmobil. com / AviationGlobal / Files / WorldJe tFuelSpecifications2 0 05. pdf

2. Hemighaus, G. et al. Alternative Fuel Fuels: A supplement to Chevron's aviation fuels technical review. Chevron Corporation (2006). 3. Aatola, H., Larmi, M., Sarjovaara, T. & Mikkonen, S. Hydrotreated vegetable oil (HVO) as a renewable diesel fuel: trade-off between NOx, particulate emission, and fuel consumption of a heavy duty engine. Helsinki University of Technology & In this Oil, Finland (2008). 4. Leckel, D. Diesel Production from Fischer-Tropsch: The Past, the Present, and New Concepts. Energy & Fuels 23, 2342-2358 (2009) 5. Tiwari, R. et al. Hydrotreating and hydrocracking catalysts for processing of waste soybean and refinery oil mixtures. Catalysis Communications 12, 559-562 (2011). 6. Morita T, Konishi M, Fukuoka T, Imura T, Kitamoto HK.

Characterization of the genus Pseudozyma by the formation of glycolipid biosurfactants, mannosylerythritol lipids. FEMS Yeast Research. 34: 286-292 (2007). 7. Srivastava, A. & Prasad, R. Triglycerides-based diesel fuels. Renewable and Sustainable Energy Reviews 4, 111-133 (2002). 8. Ranganathan, S.V., Narasimhan, S.L. & Muthukumar, K. An overview of enzymatic production of biodiesel. Bioresource Technology. 99, 3975-3981 (2008).

Lisbon, May 15, 2014

Claims (11)

1. Production of liquid fuel for aviation and winter diesel for land transport and nautical transport, using mixtures of organic compounds of chains between 4 and 16 carbons, characterized in that the fuel is obtained by a chemical reaction from microbial glycolipids with lipid chains composed of 6 to 14 carbons. Fuel production according to claim 1, characterized in that said microbial glycolipids are mannitolithritol or rhamnolipid lipids. Fuel production according to claim 1 and 2, characterized in that said microbial glycolipids are obtained from vegetable or animal oils, lignocellulosic materials, sugars or alcohols. Fuel production according to the preceding claims, characterized in that the mixture of organic compounds comprises mixtures of hydrocarbons having from 4 to 14 carbon chains or mixtures of esters having from 7 to 16 carbon chains. Fuel production according to the preceding claims, characterized in that the mixture of hydrocarbons having 4 to 14 carbon chains, produced from microbial glycolipids, is produced by the hydrogen catalytic reaction of the microbial glycolipid. Fuel production according to claims 1 to 4, characterized in that the mixture of esters with chains between 7 and 16 carbons, produced from microbial glycolipids, is produced by chemical transesterification of the microbial glycolipid with an alcohol. Fuel production according to the preceding claims, characterized in that the mixture of esters or the mixture of hydrocarbons produced from the microbial glycolipids is used as such or combined with diesel of fossil origin. Fuel production according to claims 1 to 5, characterized in that the mixture of hydrocarbons produced from the microbial glycolipids is combined up to 50% (v / v) with liquid fuels of aviation fossil origin. Fuel production according to claims 1 to 4 and 6 above, characterized in that the mixture of esters produced from the microbial glycolipids is combined up to 20% (v / v) with liquid fuels of aviation fossil origin. Use of the fuel defined in claims 1 to 6 and 8 to 9, characterized in that the liquid fuel is used in aviation liquid fuels. Use of the fuel defined in claims 1 to 7, characterized in that the fuel is employed in winter gas oil for land or nautical transport. Lisbon, May 15, 2014