Classifications

• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
  • C07C11/00—Aliphatic unsaturated hydrocarbons
  • C07C11/21—Alkatrienes; Alkatetraenes; Other alkapolyenes
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61P—SPECIFIC THERAPEUTIC ACTIVITY OF CHEMICAL COMPOUNDS OR MEDICINAL PREPARATIONS
  • A61P3/00—Drugs for disorders of the metabolism
  • A61P3/02—Nutrients, e.g. vitamins, minerals
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07J—STEROIDS
  • C07J9/00—Normal steroids containing carbon, hydrogen, halogen or oxygen substituted in position 17 beta by a chain of more than two carbon atoms, e.g. cholane, cholestane, coprostane
• • C—CHEMISTRY; METALLURGY
  • C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
  • C11B—PRODUCING, e.g. BY PRESSING RAW MATERIALS OR BY EXTRACTION FROM WASTE MATERIALS, REFINING OR PRESERVING FATS, FATTY SUBSTANCES, e.g. LANOLIN, FATTY OILS OR WAXES; ESSENTIAL OILS; PERFUMES
  • C11B3/00—Refining fats or fatty oils
  • C11B3/12—Refining fats or fatty oils by distillation
• • C—CHEMISTRY; METALLURGY
  • C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
  • C11C—FATTY ACIDS FROM FATS, OILS OR WAXES; CANDLES; FATS, OILS OR FATTY ACIDS BY CHEMICAL MODIFICATION OF FATS, OILS, OR FATTY ACIDS OBTAINED THEREFROM
  • C11C3/00—Fats, oils, or fatty acids by chemical modification of fats, oils, or fatty acids obtained therefrom
  • C11C3/003—Fats, oils, or fatty acids by chemical modification of fats, oils, or fatty acids obtained therefrom by esterification of fatty acids with alcohols
• • C—CHEMISTRY; METALLURGY
  • C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
  • C11C—FATTY ACIDS FROM FATS, OILS OR WAXES; CANDLES; FATS, OILS OR FATTY ACIDS BY CHEMICAL MODIFICATION OF FATS, OILS, OR FATTY ACIDS OBTAINED THEREFROM
  • C11C3/00—Fats, oils, or fatty acids by chemical modification of fats, oils, or fatty acids obtained therefrom
  • C11C3/02—Fats, oils, or fatty acids by chemical modification of fats, oils, or fatty acids obtained therefrom by esterification of fatty acids with glycerol

Definitions

• the present invention relates to a process for the simultaneous extraction of squalene, sterols and vitamin E (tocopherols and tocotrienols) contained in condensates of physical refining and / or in distillates of deodorization of vegetable oils. It is in the technical field of lipid treatments.
• Vegetable oils contain between 0.5% and 2% of a part that can not be saponified, commonly called "unsaponifiable". The qualitative and quantitative composition of this unsaponifiable varies according to vegetable oils, but apart from a few exceptions, the sterol family is the most important part, ⁇ -sitosterol still being the most abundant of them. In addition to the sterols, there are four families of products: tocopherols and tocotrienols, triterpene alcohols, aliphatic alcohols and hydrocarbons.
• Tocopherols ( ⁇ , ⁇ , Y, ⁇ ) and tocotrienols ( ⁇ , ⁇ , Y, ⁇ ) are particular phenols that are grouped under the name Vitamin E, found in the human body mainly in the form of ⁇ -tocopherol.
• Triterpene alcohols by the name of their molecular structure, are chemical intermediates in the biosynthesis of sterols and are found next to them in the unsaponifiable.
• Aliphatic alcohols by the name of their carbon chain comparable to that of fatty acids, are present in the unsaponifiable in a relatively modest quantity.
• Hydrocarbons are divided into two classes: aliphatic hydrocarbons (paraffins and olefins) and terpene hydrocarbons (including squalene and carotene).
• paraffins and olefins paraffins and olefins
• terpene hydrocarbons including squalene and carotene.
• squalene which by far is the compound weighted the most important in its unsaponifiable.
• palm oil carotene is one of the important components of unsaponifiable matter. All these compounds play in varying degrees an important role in different sectors that range from food to cosmetics, by transposing their beneficial effects on plant cells, to those of the human body.
• Sterols are known for their hypocholesterolemic properties. There is thus a large number of products on the market, including margarines containing phytosterols. Sterols are also used in the pharmaceutical industry for the manufacture of steroids. Finally in cosmetics they enter many formulations because of their properties both emulsifying, anti-inflammatory and anti-aging.
• Vitamin E is, like any phenol, a natural antioxidant whose antioxidant effects are exerted both in vivo and in vitro. Its vitamin effects especially in the field of reproduction have been known for a very long time. It is therefore a product used in the field of pharmacy, cosmetics and food products. Squalene is a hydrocarbon (C30H50) present in the plant kingdom as well as in the animal kingdom. Being the precursor of cholesterol after its bioepoxidation, it therefore plays indirectly in vivo, a fundamental role in the constitution of cell membranes. It is also present at 15% in human sebum. Its terpene nature gives it special physicochemical qualities, which make it an exceptional emollient. In its fully hydrogenated stable form of perhydrosqualene (C30H62), it has been in use for over fifty years in a large number of cosmetic formulations because of its high skin compatibility and its emollient and hydrating properties.
• C30H50 hydrocarbon
• deodorization conditions vacuum of the order of 2 to 4 mbar, temperature which can reach 250 ° C, entrainment with the water vapor
• deodorization conditions not only favor the elimination of the odorous products and that of the acids - AT -
• DD and CRPH the components of the unsaponifiable are obviously accompanied by fatty acids that are still the major components.
• fatty acids that are still the major components.
• glycerides mono, di and triglycerides
• the enrichment coefficients of the unsaponifiable compounds in DD or CRPH, relative to the starting oil, depend on the volatility of these different compounds, itself linked to their boiling points. The lower the boiling point of a compound, the greater the enrichment of this product in DDs and CRPHs.
• the enrichment coefficients in the DDs are for example 400, 250, 80 and 25 respectively for non-squalene hydrocarbons, for squalene, for tocopherols and for sterols.
• the DDs of this oil are thus obtained at exploitable levels for the extraction of the components of its unsaponifiable material with, for example, 5.9% non-squalene hydrocarbons, 4.9% squalene, 6.5% tocopherols and , 8% of sterols.
• the enrichment coefficients in CRPH are, for example, 50, 20, 13 and 10, respectively for non-squalene and non-carotene hydrocarbons, for squalene, for tocopherols and for sterols.
• the CRPHs of this oil have 0.4% non-squalene (and non-carotene) hydrocarbons, 0.6% squalene, 0.5% tocopherols and 0.5% sterols.
• DDs containing for example: 2.0% squalene, 10.8% tocopherols, 12.1% sterols.
• DD is a raw material of choice for the extraction of unsaponifiables: squalene, other vegetable hydrocarbons, vitamin E
• the known methods for extracting unsaponifiable mainly concern the extraction of one or two unsaponifiables: that of sterols and that of vitamin E, for the most part.
• the extraction of squalene from CRPH and DD from olive oil is well known, no method seems to describe the extraction of squalene from the by-products of the refining of other vegetable oils.
• the hydrocarbons other than squalene, contained in vegetable oils, if their presence is described in the literature, to the knowledge of the applicant, no document seems to disclose a method of extraction or the use of these hydrocarbons.
• sterol crystallization is generally used.
• the most used esterification technique consists in reacting, in the presence of a catalyst, the fatty acids of DD or CRPH with a short aliphatic alcohol, in general methanol, to transform them into esters. fatty acids, products more volatile than sterols and vitamin E.
• This method is described for example in US Patent 5,190,618 (Abdul G. et al), US 5,703,252 (Tracy K. et al), and US 5,627,289 (Lutz J. et al).
• the residue obtained is then subjected to a second molecular distillation which will make it possible to obtain a distillate enriched in tocopherols, still containing fatty acids.
• the residue of this second distillation contains most of the sterols as sterids. In such processes, most of the hydrocarbons and much of the squalene are removed with the fatty acids.
• Sterols and tocopherols are then recovered in the same way as for the direct saponification of DDs.
• squalene is likely to be altered by isomerization upon acidification of the filtrate containing the soaps.
• a large part of the squalene is lost during the distillation of the methyl esters, given their neighboring boiling points.
• CRPH olives relatively rich in squalene (5% to 15%), containing little sterols and vitamin E, and naturally rich in fatty acids (50% to 80%), the fatty acids are molecularly weighed down by esterification with glycerol in the form of triglycerides. Squalene is then separated from the triglycerides by distillation.
• Patent EP 1,394,144 discloses a process for the simultaneous extraction of vitamin E, phytosterols and squalene from palm oil, comprising the steps of: a) conversion of crude palm oil to methyl esters of palm oil; b) short-path distillation of the three-stage methyl esters of palm oil obtained in step (a) to give phytonutrients; c) saponification of the phytonutrient concentrate of step (b); d) crystallization of phytosterols; and e) solvent partitioning of vitamin E and squalene.
• Synthetic vitamin E is a mixture of eight stereoisomers of ⁇ -tocopherol. Only one of these stereoisomers (12.5%) is similar to d- ⁇ -tocopherol. Hence a higher biological activity of natural vitamin E compared to synthetic vitamin E. With respect to antioxidant activity, natural vitamin E is a mixture of four alpha, beta, gamma and delta tocopherol isomers.
• the antioxidant activity of the isomers is ⁇ > ⁇ > ⁇ > ⁇ , giving a fundamental advantage to natural vitamin E as an antioxidant. It therefore appears particularly advantageous to reduce the costs of extraction of natural vitamin E and extract it by truly natural processes so that its benefits of bioavailability and antioxidant activity can be valued.
• the main raw material still remains the liver oil of small sharks of great depths which contains according to the species of 40 to
• vitamin E or even IP-labeled sterols which have been at one time or another extraction processes in contact with hexane and methanol or other solvents of petroleum origin, can not claim these labels of natural products that can be used in "organic" formulas.
• the main objective of the invention is to propose a method for simultaneously extracting squalene, sterols and vitamin E, in order to better valorize those unsaponifiables that are not available in known industrial processes. of the prior art.
• Another object of the invention is to provide a method for producing simultaneously by a global process from DD and CPRH vegetable oils, four unsaponifiables: squalene, vegetable hydrocarbons, vitamin E and sterols.
• the invention also aims to be able to extract unsaponifiables mentioned above, by soft chemistry techniques, without the use of petroleum solvents, in order to claim labels of natural products.
• the invention further aims to provide a global industrial process for the extraction of different components of the unsaponifiable vegetable oils, and therefore to reduce their cost of production. Disclosure of the invention.
• the solution proposed by the invention is a process for extracting squalene, sterols and vitamin E contained in physical refining condensates and / or in vegetable oil deodorization distillates, said process comprising the following steps: ) transformation of the fatty acids, glycerides and sterids contained in said condensates and / or said distillates, to obtain a product based on alkyl esters, squalene, plant hydrocarbons, sterols and vitamin E, b ) staged distillation of the product obtained in step a) established to recover on the one hand a concentrate of sterols and vitamin E and on the other hand a concentrate of alkyl esters, squalene and vegetable hydrocarbons, c ) crystallization of the concentrate of sterols and vitamin E obtained in step b), mixed with hydrocarbons, to recover on the one hand sterols and on the other hand a concentrate of vitamin E in solution in said hy hydrocarbons, d) distillation of the
• the vegetable hydrocarbons separated at the end of step f) are used to participate in the crystallization of the sterols in step c).
• the staged distillation of step b) is preferably carried out by performing: b.1) a first distillation established to extract a fraction of the vegetable hydrocarbons and a fraction of the alkyl esters, b.2) a second distillation established to extract the majority of the alkyl esters of the residue obtained in step a), b.3) a third distillation established to entrain residual alkyl esters, squalene and residual plant hydrocarbons, without causing sterols and vitamin E less volatile.
• the first distillation is advantageously carried out on a packed column representing the equivalent of twenty theoretical plates, under a vacuum of between 3 mb and 10 mb, preferably between 4 mb and 7 mb, at a heating temperature of between 160 ° C. and 180 ° C. ° C, and at a top temperature of between 120 ° C and 150 ° C, preferably between 140 ° C and 145 ° C.
• the second distillation is advantageously carried out on a packed column representing the equivalent of ten theoretical plates, under a vacuum of between 10 mb and 40 mb, preferably between 20 mb and 30 mb, at a heating temperature of between 220 ° C. and 250 ° C.
• the third distillation is advantageously carried out on a packed column representing the equivalent of ten theoretical plates, under a vacuum of between 1 mb and 10 mb, preferably between 2 mb and 5 mb, at a heating temperature of between 220 ° C. and 260 ° C. ° C, preferably between 240 ° C and 250 0 C, and at a column top temperature between 200 0 C and 250 0 C, preferably between 220 ° C and 230 ° C.
• the light hydrocarbons obtained from the first distillation can be recovered by further providing the steps of: g.1) conversion of the fraction of the alkyl esters extracted in step b1) into triglycerides, g.2) distillation of the product obtained at the end of step g.1) established to separate said triglycerides from hydrocarbons plants. These can be combined with the separated hydrocarbons at the end of step f), the assembly being used to crystallize the sterols in step c).
• the alkyl esters (step a) are advantageously obtained by means of: ⁇ an esterification of the fatty acids with a short alcohol, chosen from primary and secondary C1 to C3 alcohols, and in the presence of an acid catalyst. This esterification is advantageously carried out under the following conditions:
• the reaction temperature is less than 95 ° C
• the esterification alcohol is in molar excess in a ratio greater than 5 relative to the fatty acids
• the acid catalyst is completely neutralized at the end of the esterification of a trans-esterification of glycerides and sterids with a short alcohol, chosen from primary and secondary C 1 to C 3 alcohols, and in the presence of a basic catalyst .
• This transesterification is advantageously carried out under the following conditions:
• the reaction temperature is below 100 ° C., the basic catalyst is completely neutralized at the end of transesterification.
• the trans-esterification and esterification mentioned above are both carried out with ethanol of vegetable origin.
• bioethanol as a short alcohol
• vegetable glycerol and vegetable hydrocarbons resulting from the process the process Extraction object of the invention can be carried out industrially, without any solvent of petroleum origin. This characteristic makes it possible on the one hand to claim the labels characterizing products obtained by natural physical and chemical processes and on the other hand to claim their use, as natural products, in combination with products that claim the "organic" labels. .
• step f) For the extraction and purification of squalene, prior to step f), said squalene and the hydrocarbons separated at the end of step e) can be saponified to remove any residual saponifiable products.
• step f) is advantageously carried out by distillation on a column of height equivalent to twenty theoretical plates, under a vacuum of between 2 mb and 10 mb, preferably between 4 mb and 8 mb, the product to treating being injected at the top of the column at a temperature of between 200 ° C. and 230 ° C., preferably 215 ° C., nitrogen being injected simultaneously at the bottom of the column for countercurrent operation.
• the distilled hydrocarbons still containing a fraction of squalene can be re-injected into the column to obtain a percentage of squalene less than 10%.
• a step of frigmentation is carried out on the squalene obtained at the end of step f).
• step d) the distillation of step d) is advantageously carried out on a packed column representing the equivalent of ten theoretical plates, under a vacuum of between 0.2 mb and 5 mb, preferably 1 mb at a heating temperature of between 200 ° C. and 240 ° C., preferably 220 ° C., and at a top temperature of between 180 ° C. and 220 ° C., preferably 200 ° C. Description of the figures.
• deodorizing distillates from chemical refining and physical refining condensates (CRPH) from vegetable oils are a raw material of choice for the production of vegetable oils.
• DD or CRPH oils can be used, a selection may however be made either for the traceability of materials, or to obtain a specific unsaponifiable higher concentration than another.
• sunflower condensates contain a very high proportion of d- ⁇ -tocopherol
• palm oil condensates contain a very high proportion of tocotrienols (80%) compared to tocopherols (20%).
• Residues of grapeseed oil can also be sought if you want to get a good concentration of tocotrienols.
• Condensates of olive oil, olive pomace or those of amaranth oil (even richer in squalene olive oil) will be sought if priority is given to squalene.
• Step a) - Obtaining alkyl esters This step transforms the fatty acids, glycerides and sterids contained in the DD and / or CRPH, to obtain a product based on alkyl esters, squalene, vegetable hydrocarbons, sterols and vitamin E In particular, this step involves the conversion of the free fatty acids and those combined into alkyl esters under conditions avoiding the isomerization of squalene, thus making it possible to obtain a commercial squalene.
• esterification and trans-esterification of fatty acids from vegetable oil refining by-products have been known for a long time. However, the risks of degradation of squalene during the esterification reaction are not described. The Applicant has now defined esterification and trans-esterification conditions that will not degrade squalene.
• squalene is a very reactive molecule because of the presence of six double bonds and its particular structure of terpene nature that can give rise, in the presence of protons, to the formation of relatively stable tertiary carbocations, which can evolve either towards the formation of geometric and position isomers or towards the formation of cyclic isomers.
• terpene terpene
• cyclic isomers These two families of isomers help to reduce the purity of squalene.
• the position isomers and the geometric isomers which only concern the position of the double bond on the carbon chain and their geometric conformation respectively, will be transformed into squalane (or perhydrosqualene) by hydrogenation. .
• the esterification (step a.1) is carried out by a short alcohol, chosen from primary and secondary carbon condensation alcohols of between one and three, preferably ethanol of vegetable origin, in the presence of an acid catalyst selected from sulfuric acid and para toluenesulphonic acid (APTS).
• a short alcohol chosen from primary and secondary carbon condensation alcohols of between one and three, preferably ethanol of vegetable origin, in the presence of an acid catalyst selected from sulfuric acid and para toluenesulphonic acid (APTS).
• APTS para toluenesulphonic acid
• the acid catalyst proton donor, presents a danger vis-à-vis the risk of isomerization should be avoided.
• the Applicant has shown that the APTS more advantageously causes the formation of isomers of squalene. Sulfuric acid will therefore be preferred for esterification.
• the desirable concentration of acid catalyst is 0.1% maximum relative to the mass of CRPH or DD to be esterified.
• the esterification method described by Martinenghi for introducing methanol vapors into fatty acids in the presence of acidic catalyst is the one which has created the most isomers of squalene, even with a temperature of 70 ° C.
• the esterification alcohol is preferably in molar excess in a minimum ratio of 5, and preferably 10, relative to the fatty acids. Since temperature is a factor facilitating the isomerization of squalene, an esterification at a temperature below 95 ° C., preferably at a temperature of between 80 ° C. and 90 ° C. under reflux of alcohol, has been retained.
• the acid catalyst must be completely neutralized in order to prevent the residual acidity from causing isomerizations of squalene during the subsequent steps of the process carried out at higher temperatures.
• This neutralization of the acid catalyst is done by ethanolic sodium or ethanolic potassium hydroxide. We then completely evaporates the excess alcohol as well as the water coming from the esterification.
• the anhydrous product thus obtained is then subjected to a transesterification (step a.2) in the presence of a short alcohol identical to that of the fatty acid esterification, chosen from primary and secondary alcohols, of condensation of carbon included between one and three, preferably vegetable origin ethanol, in the presence of a basic catalyst, preferably sodium ethoxide, to convert the pre-existing glycerides into ethyl esters of fatty acids.
• a short alcohol identical to that of the fatty acid esterification chosen from primary and secondary alcohols, of condensation of carbon included between one and three, preferably vegetable origin ethanol
• a basic catalyst preferably sodium ethoxide
• alkyl alcohols methanol, propanol, etc.
• trans-esterification the combined sterols in the sterides are found in free form.
• a strong acid HbSO 4 or HCl
• the ethanol is evaporated and the glycerol decanted is discarded.
• the product is then washed to neutrality.
• the trans-esterification reaction is carried out at a temperature below 100 ° C., preferably at a temperature of between 80 ° C. and 90 ° C. under reflux of alcohol.
• Bioethanol will be the alcohol preferentially used with sulfuric acid as a catalyst, to be able to claim a label of products obtained by natural processes, as described later.
• Step b) Staged distillation of the product obtained at the end of step a.
• This step makes it possible to recover on the one hand a concentrate of sterols and vitamin E and on the other hand a concentrate of alkyl esters, squalene and vegetable hydrocarbons.
• the product resulting from stage a) is subjected to three successive fractional distillations at different temperatures, under mild conditions making it possible to avoid the degradation of the unsaponifiables during these stages, especially vitamin E, particularly during the course of the process.
• third distillation A first distillation will make it possible to extract a fraction of the vegetable hydrocarbons (excluding squalene) and a fraction of the alkyl esters.
• a second distillation will make it possible to extract most of the alkyl esters from the residue obtained in step a), without causing squalene.
• a third distillation will make it possible to drive squalene with the heavier residual alkyl esters, without causing vitamin E and sterols which are much less volatile.
• Step b.1) First distillation.
• the alkyl esters are subjected to a first distillation of the hydrocarbons present in the esterified CRPH and DD.
• the objective is to distill the lighter hydrocarbons corresponding to a C8 to C15 cut, which are very odorous, even irritating, certainly also because of the presence of aldehydes from the oxidation of fats.
• a second objective is to obtain a vegetable hydrocarbon fraction, not having the disadvantages of the first fraction, which can be used during the process, replacing petroleum solvents, as explained in the following patent.
• This first distillation of the hydrocarbons is carried out by fractional distillation on a column filled with wire mesh type packing of height equivalent to twenty theoretical plates. Distillation carried out at a heating temperature of between 160 ° C. and 180 ° C. and a top-of-column temperature of between 120 ° C. and 130 ° at the top of the column and a vacuum of between 3 mb and 10 mb, preferably between 4 and 10 mbar. mb and 7, mb makes it possible to distill the lighter hydrocarbons, mainly C8 to C15, without causing alkyl esters.
• this fraction represents less than 20% of the plant hydrocarbons (non-squalene) present in the CRPH and DD and a large part of the hydrocarbons would then be lost during the second distillation of the esters, being eliminated with the distillate. It is therefore preferred to carry out a distillation of the hydrocarbons with a temperature of between 120 ° C. and 150 ° C., preferably between 140 ° C. and 145 ° C. at the top of the column and a vacuum of 4 to 7 mbar which makes it possible to recover more than 50%. of the plant hydrocarbons (non-squalene) present in the CRPH and DD and to entrain only about 20% of light alkyl esters in the distillate.
• the hydrocarbon fraction obtained is composed of hydrocarbons ranging from C8 to C22, with a major fraction composed of hydrocarbons ranging from C15 to C22.
• the distillate of the said hydrocarbon distillation at 140 ° C.-145 ° C. will be taken up in step g) described below, for the purification of vegetable hydrocarbons.
• step b.1 The residue of the first distillation of the hydrocarbons (step b.1) is then subjected to a second fractional distillation, in a system operating continuously under vacuum, comprising a falling film evaporator or scraper equipped with a fractionation column filled with packing.
• a second fractional distillation in a system operating continuously under vacuum, comprising a falling film evaporator or scraper equipped with a fractionation column filled with packing.
• this separation is carried out on a column of height equivalent to ten theoretical plates, under a vacuum of between 10 mb and 40 mb, preferably between 20 mb and 30 mb, by mass-heating the alkyl esters at a temperature of temperature between 220 ° C and 250 ° C, preferably 230 ° C, with a temperature at the top of the column between 180 ° C and 220 0 C, preferably between 200 0 C and 205 ° C. Beyond these temperatures, there is a risk of reforming sterids and / or driving a lot of squalene. Regular reflux inside the column is advantageously provided not to cause squalene. This step makes it possible to entrain the greater part of the esters.
• the distillate of the second distillation is essentially composed of alkyl esters and contains less than 1% of squalene, sterols and vitamin E.
• the residue of said second distillation essentially contains the heavier residual alkyl esters and the remainder unsaponifiables.
• step b.2 The residue from step b.2) is subjected to a third distillation under vacuum. Since squalene and the heavier alkyl esters are very difficult to separate by distillation, the third distillation is intended to jointly distill these residual esters and squalene, leaving in the residue less volatile sterols and vitamin E. In this third distillation the temperature is limited so as to avoid thermal isomerization of squalene. Too high a distillation temperature also favors the partial reformation of sterids by transesterification of the sterols with the ethyl esters, as well as the thermal transformation of these sterren into sterenes, with release of fatty acids, resulting in a loss of sterols. It is therefore necessary to avoid the disadvantages of batch distillations (long residence time and interactions between vapors and liquid to be crossed). Distillation tests on a molecular distillation reactor did not achieve the desired separation.
• the distillation device comprises a falling or scraped film evaporator equipped with a fractionation column filled with packing.
• the distillation system used is the same as that used during the second distillation.
• the said distillation device operating as a thin layer of liquid in the falling or scraped film reactor not only promotes instant evaporation of the vapors but also a short duration of contact with the heating system, thus making it possible to send the filled column, vapors that have not undergone prolonged thermal stress.
• this third distillation is carried out with a product heated between 220 ° C. and 260 ° C., preferably between 230 ° C.
• a top-of-column temperature of between 200 ° C. and 250 ° C., preferentially between 220 ° C and 230 ° C, under a vacuum between 1 mb and 10 mb, preferably between 2 mb and 5 mb and a packing representing 10 theoretical plates.
• Regular reflux inside the column is necessary not to cause tocopherols and vitamin E.
• This third distillation makes it possible to obtain a distillate containing squalene with the heavier alkyl esters and, on the other hand, a residue containing mainly sterols and vitamin E.
• Step c) Crystallization of the sterols.
• the residue of the third distillation of the alkyl esters (step b.3), highly concentrated in sterols and vitamin E, will be used for the extraction of sterols and vitamin E.
• concentration of sterols and vitamin E some processes use prior purification by saponification. This saponification generally made in methanolic or ethanolic medium requires a significant dilution of the soaps formed, thus the implementation of large amounts of solvents. This saponification step is avoided in the present process.
• step a the trans-esterification of the triglycerides after esterification of the fatty acids (step a) and the third distillation of the esters at the same time as that of squalene (step b.3), made it possible to eliminate almost all the triglycerides and esters.
• the removal of this saponification step thus simplifies the process and minimizes the losses of unsaponifiables retained in the soaps.
• the concentrate of vitamin E and sterols obtained in the residue of the third distillation of the esters (step b.3) is then subjected directly to crystallization, without going through a saponification step.
• the known methods recommend to put the concentrate in solution in hexane, in the presence of ethanol or methanol and water. These methods are widely described in the literature relating to the extraction of sterols and can of course be used for the separation of sterols and vitamin E from the present process.
• a particularly remarkable feature of the invention is to be able to replace this crystallization in solvent medium of petroleum origin by crystallization in admixture with the plant hydrocarbons generated by the process described above.
• the concentrate of sterols and vitamin E was thus dissolved in vegetable hydrocarbons in a ratio of 1 to 4.
• the mixture is then heated to 80 ° C to dissolve the solid compounds in plant hydrocarbons.
• the solution obtained is then gradually cooled (5 ° C. to 10 ° C. per hour) to room temperature, 25 ° C., with gentle stirring, so as to promote the optimal development of the crystals.
• the crystals are filtered by incorporating 2% silica (commercial grade dicalite). During this first frigmentation, 95% of the sterols involved are recovered.
• the filtrate contains vitamin E, a small percentage of squalene, ethyl esters and impurities, in solution in plant hydrocarbons.
• This filtrate is then subjected to distillation in a reactor of the type used in steps b.2 and b.3: scraped film evaporator equipped with a column of ten theoretical plates.
• the thin layer configuration and the reduced heating time are necessary to avoid degradation of vitamin E.
• the evaporator is heated to a temperature between 200 ° C and 240 ° C, preferably 220 ° C.
• the temperature at the top of the column is between 180 ° C. and 220 ° C., preferably 200 ° C.
• the reflux of the esters is used under a vacuum of between 0.2 mb and 5 mb, preferably 1 mbar. Most of the hydrocarbons, squalene and esters are thus distilled. The distillate is then recycled in the process for obtaining plant hydrocarbons.
• the residue, very rich in vitamin E will be used as it is or will then be purified according to the techniques known to those skilled in the art, for example by passing through an ion exchange column. Vitamin E can also be concentrated by known methods those skilled in the art and in particular by passing over anionic resins and molecular distillations.
• Step e Transformation of alkyl esters and recovery of squalene and plant hydrocarbons.
• the distillate from the third distillation of the esters contains not only squalene and the heavier alkyl esters which are the majority products, but also hydrocarbons.
• the latter have a carbon condensation mainly between C17 and C22 and represent 10% to 20% of the quantities of squalene, according to the origins of DD and CRPH.
• the distillate from the third distillation (step b.3) is first subjected to transesterification (step e.1) with glycerol, preferably vegetable glycerol, to convert the alkyl esters to triglycerides.
• the said trans-esterification reaction catalyzed by 0.05% of 50% sodium hydroxide solution, is carried out at a heating temperature of between 180 ° C. and 230 ° C., preferably between 200 ° C. and 210 ° C., under a vacuum of between 20 mb and 40 mb, preferably 30 mb, in a reactor equipped with a thermoregulated reflux column for distilling the released short alcohol while trapping glycerol.
• the squalene and the hydrocarbons are then separated from the triglycerides (stage e.2) by distillation at a heating temperature of between 220 ° C. and 260 ° C., preferably between 240 ° C. and 250 ° C., and including a head temperature. Between 200 ° C and 250 ° C, preferably between 220 ° C and 230 ° C, with a vacuum of between 0.2 mb and 5 mb, preferably 1 mb, in the case of a batch distillation.
• This reaction can also be carried out by molecular distillation with a temperature of between 220 ° C. and 230 ° C. and a vacuum of less than 0.1 mb.
• Step f) Extraction and purification of squalene.
• the squalene and the hydrocarbons obtained at the end of step e) are optionally saponified to remove any residual saponifiable products.
• Squalene may still contain up to 10% to 20% residual hydrocarbons, most of which have a lower molecular weight than squalene.
• the squalene obtained at the end of stage e), or possibly at the end of the saponification stage is separated from the residual hydrocarbons by distillation and preferably by stripping at the end of the stage. 'nitrogen.
• the latter is carried out on a column of height equivalent to 20 theoretical plates, under a vacuum of between 2 mb and 10 mb, preferably between 4 mb and 8 mbar.
• the product is injected at the top of the column at a temperature of between 200 ° C.
• the distilled fraction mainly contains carbon main condensation hydrocarbons between C17 and C22.
• the said hydrocarbon fraction may still contain between 20% and 30% of squalene. It may therefore be subjected to a second and third passage in the column to better separate plant hydrocarbons, which contain at the end of operation a percentage of squalene less than 10%.
• the squalene obtained after stripping may still contain waxes and paraffins which could not be distilled off.
• a step of frigmentation is then necessary.
• the so-called frigmentation involves cooling at a temperature between 0 ° to + 5 ° C, in a reactor slowly stirred for the ripening of the crystals. These are separated from the liquid part consisting of squalene by filtration on a filter press, after adding 2% silica (commercial grade dicalite), to facilitate filtration.
• the vegetable hydrocarbons thus purified have a flash point greater than 100 ° C. They have a cloud point at 0 ° C and a freezing point at -5 ° C.
• step g They are therefore suitable for use directly as a solvent to participate in the crystallization of the sterols (step c) or in a mixture with the fraction obtained during the first distillation of the alkyl esters (step b.1), after purification described below. after in step g).
• Step g Extraction and purification of plant hydrocarbons.
• the fraction of hydrocarbons extracted by distillation during step b.1), before the distillation of the alkyl esters, has a carbon condensation mainly ranging from C8 to C22. This fraction contains about 20% of alkyl esters.
• the separation of these vegetable hydrocarbons and of these alkyl esters proving impossible by distillation, said hydrocarbon fraction will be subjected to an inter-esterification step (step g.1) with glycerol, preferably vegetable glycerol, to convert the alkyl esters to triglycerides.
• the reaction is carried out in the presence of 0.005% to 0.01% of a basic catalyst (50% sodium hydroxide or potassium hydroxide solution) at a temperature of between 180 ° C.
• the said inter-esterification product of the plant hydrocarbons is then distilled to separate the triglycerides from the said hydrocarbons (step g.2).
• This distillation is advantageously carried out in two phases.
• a first phase makes it possible to distill the low molecular weight hydrocarbons (carbon condensation between C8 to C15, mainly) which represent approximately 20% of the hydrocarbon fraction.
• This fraction will be eliminated because it is very fragrant, irritating and has a flash point lower than 100 ° C.
• This fraction is obtained by distillation on a column filled with stainless steel mesh type packing, having a height equivalent to ten theoretical plates, at a maximum temperature of 125 ° C at the top of the column, under a vacuum of 5 to 7 mb.
• a second phase then makes it possible to distil, on the same column, the remainder of the hydrocarbons at a column temperature of 215 ° C.
• the distillate is composed of hydrocarbons of chain lengths greater than dodecane and is much less odorous. There is thus obtained a condensation hydrocarbon fraction of C12 to C22 carbons.
• the second vegetable hydrocarbon fraction obtained in this step g) will then be mixed with the vegetable hydrocarbon fraction obtained at the end of step f), thereby obtaining a fraction of vegetable hydrocarbons having a main carbon condensation. mainly from C12 to C22.
• These plant hydrocarbons have a cloud point below 0 ° C and a freezing point below -5 ° C, which makes them suitable for use as solvents for the crystallization of sterols in the following process.
• the process that is the subject of the invention preferably induces the constitution of a section of plant hydrocarbons recovered during the first distillation (step g), as well as during the purification of squalene by stripping (step f).
• a particularly remarkable feature of the invention is to use these plant hydrocarbons during the process to advantageously replace petroleum solvents for the extraction of sterols and vitamin E (step c).
• Example 1 Esterification by bioethanol of a deodorization distillate of sunflower oil - step a).
• oleic sunflower DD which has the following composition:
• This condensate is mixed with 620 grams of anhydrous ethanol, ie a molar excess of ethanol relative to the fatty acids of 10. 1 gram of concentrated sulfuric acid is added, ie 0.1% relative to the condensate mass. charge.
• the stirred flask is purged several times with nitrogen and then heated to 90 ° C. The reaction is carried out for 4 hours under reflux of the ethanol.
• the sulfuric acid is neutralized with an ethanolic 0.5N sodium hydroxide solution with stirring for 30 minutes.
• the excess ethanol and the water of reaction are distilled under atmospheric pressure, then under a vacuum of 50 mbar and a temperature of 100 ° C.
• the final product has an acid number of 0.7 and squalene has not been isomerized.
• Example 2 Esterification by bioethanol of a sunflower DD - step a).
• 500 g of sunflower DD identical to those of Example 1 are introduced into a 1-liter autoclave. This condensate is mixed with 154.9 grams of anhydrous bioethanol, ie a molar excess of ethanol / fatty acids of 5.
• 0.5 g of concentrated sulfuric acid is added, ie 0.1% relative to the charged condensate mass.
• the reactor is heated progressively to 90 ° C, stirring for one hour, the pressure reached being 2.5 bar.
• the reaction medium is neutralized with an ethanolic solution of 0.5 N sodium hydroxide, for 30 minutes with stirring.
• the ethanol is then distilled at atmospheric pressure, then under a vacuum of 50 mbar and a temperature of 100 ° C at the end of distillation, to remove the water from the esterification.
• An anhydrous product having an acid number of 0.8 is obtained and squalene is not isomerized.
• Example 3 Ethanolysis of a sunflower DD esterified with bioethanol - step a).
• Example 1 In a 5-liter flask is charged with 1000 grams of the ester product in Example 1 which contains 25.8% triglycerides and 11.2% sterols present in esterified form, which corresponds to 1 mole of ester. 20 moles of anhydrous bio-ethanol (molar excess of 20), ie 920 grams of bioethanol, in which 1% by weight of sodium had previously been dissolved, were added in order to generate the sodium alkoxide in situ. The flask is then heated with stirring, at reflux of ethanol, at 80 ° C. for 2 hours. The sodium present in the form of sodium ethoxide is then neutralized with a 0.5N sulfuric acid solution. The ethanol is first distilled under atmospheric pressure and then under a reduced pressure of 50 mbar.
• the sodium sulphate formed during the neutralization is removed by washing with water. All glycerides were converted to ethyl esters as well as pre-existing steroids, resulting in the effective release of sterols. Three washes are then carried out with distilled water at 80 ° C. so as to eliminate the traces of mineral acidity present in the medium.
• Example 4 Ethanolysis of Sunflower DD Esterified by Bioethanol - Step a) 200 grams of DD esterified in Example 2 are introduced into a 500 ml autoclave, which corresponds to about 0.2 mole of ester, taking into account the triglyceride and steroid content of this DD. 46 grams of anhydrous ethanol are then introduced, which corresponds to a molar excess of 5 relative to the number of moles of esters to be ethanolized. 1% by weight of sodium was previously dissolved in ethanol. The reaction is conducted at 90 ° C for 2 hours at a pressure of 2.6 bar. The sodium present in the form of sodium ethoxide is then neutralized with a 0.5N sulfuric acid solution.
• the ethanol is first distilled under atmospheric pressure and then under a reduced pressure of 50 mbar.
• the sodium sulphate formed during the neutralization is removed by washing with water. All glycerides were converted to ethyl esters as well as pre-existing steroids, resulting in the effective release of sterols. Three washes are then carried out with distilled water at 80 ° C. in order to eliminate traces of mineral acidity present in the medium.
• Example 5 Distillation of light hydrocarbons from a sunflower oil DD - step b.1).
• Example 3 In a thermostated ampoule of 1 liter of capacity are introduced 800 grams of esterified sunflower DD ethanolized, of Example 3 which then has the following composition: ethyl esters of fatty acids 562.4 g (70.3%), Sterols and triterpene alcohols 90.4 g (11.3%), squalene 46.4 g (5.8%), total tocopherols 15.2 g (1.9%), free fatty acids 4 g (0.5%) ), non-squalene hydrocarbons, 69.6 g (8.7%), impurities (oxidative degradation products, ...) 12 g (1.5%).
• the product is introduced through a valve on a discharge over the packing of a stripping column with a useful height of 25 cm of Sulzer type BX packing with a DN diameter of 25 mm.
• the system is used under a vacuum of 4 mbar and has 20 theoretical plates.
• the flow is 200 grams per hour.
• Nitrogen is injected at the base of the column, before filling.
• the temperature at the top of the column is 145 ° C.
• the distilled product (39.1 grams) contains 69.8% non-squalene hydrocarbons, 21% fatty acid ethyl esters, 2.8% free fatty acids, 5.4% squalene and 1% impurities volatile.
• the residue (761 grams) is composed of 72.8% ethyl esters of fatty acids and represents 95.1% of the product before stripping.
• Example 5 750 grams of residue obtained after stripping (Example 5) are introduced continuously onto a scraped-film thin-film evaporator connected to a rectification column.
• the introduction rate corresponds to 150 grams per hour.
• the column has a height of 80 cm of BX Sulzer packing diameter of 60 mm.
• the system thus configured offers 10 theoretical plates.
• the evaporator is heated to 230 ° C.
• the temperature at the top of the column is maintained at 205 ° C.
• the reflux of the esters is used under a vacuum of between 20 and 30 mbar. Most of the ethyl esters are distilled.
• the distillate obtained is mainly composed of esters (97%) and traces of free fatty acids (0.3%).
• the rest is composed of hydrocarbons (2.4%) and squalene (0.2%).
• the distillate represents 456.9 grams, or 60.9% of the product that enters the distillation system.
• the residue (40% of the incoming product) is composed of 103 grams of esters, 42.7 grams of squalene, 30.6 grams of hydrocarbons, 14.9 grams of vitamin E, 90.4 grams of sterols and triterpenic alcohols and 11, 4 grams of impurities.
• Example 7 Distillation of heavy ethyl esters and squalene from a sunflower DD - step b.3).
• the residue of Example 6 is introduced into the same scraped film system described in Example 6, with a rectification column having 10 theoretical plates, at a rate of 150 grams per hour, for a controlled temperature of the chamber of evaporation between 230 ° C and 245 ° C under a vacuum of between 1 and 5 mbar. The temperature at the top of the column is maintained at 220 ° C.
• a distillate fraction of the following composition is obtained: Distilled Fraction Fraction Residue
• Vitamin E 0.2 0.1% 14.7 11.7%
• Example 7 165 grams of the distillate of Example 7 are introduced into a reactor equipped with paddle stirring, a jacket, a fractionation column.
• the distillate of Example 7 is glycerolysed in the presence of 10.2 grams of glycerol and 0.05% of 50% sodium hydroxide solution, based on the amount of distillate introduced.
• the reaction is carried out under a vacuum of 10 to 30 mbar, by heating gradually up to 210 ° C by mass. Under these conditions, in eight hours, 99% of the ethyl esters initially present are converted into triglycerides, ie 106.3 grams of converted esters.
• the glycerolysed product contains 95.3 grams of triglycerides, 40 grams of non-isomerized squalene and another 1.1 grams of residual ethyl esters. It is introduced into a molecular distillation system (UIC model KDL1) at a rate of 150 grams per hour, under a vacuum of between 0.1 and 0.05 mbar, with a preheating temperature of 90 ° C. The evaporation chamber is maintained at 230 ° C., with stirring of 400 rotations per minute. The residue of this distillation contains 0.5% squalene. To obtain a squalene of high purity, the distillate will have to undergo saponification, wintérisation, and stripping stages, ).
• UIC model KDL1 molecular distillation system
• Example 9 Purification of squalene by stripping plant hydrocarbons - step f).
• the distillate of Example 8 purified by saponification to remove traces of triglycerides and esters is very rich in squalene. But it still contains 22% of hydrocarbons that will be eliminated mainly by stripping.
• the stripping of squalene is carried out on a column of 20 theoretical plates, under a vacuum of 4 to 8 mbar. The product is injected at the top of the column at a temperature of 215 ° C. Nitrogen is injected at the bottom of the column, against the current.
• the distillate still containing 20% of squalene is subjected to a second pass on the stripping apparatus, which makes it possible to further concentrate non-squalene hydrocarbons.
• These relatively heavy hydrocarbons (mainly from C17 to C22) are poorly odorous, have a flash point above 100 ° C, a freezing point of -5 ° C, which makes them suitable for use as crystallization solvents. sterols.
• Example 10 Production of natural plant hydrocarbons during the stripping operation of squalene - step g).
• Example 5 39.1 g of the distillate of Example 5 containing 69.8% of non-squalene hydrocarbons, 21% of fatty acid ethyl esters, 2.8% of free fatty acids and 5.4% of squalene are introduced into a reactor equipped with a paddle stirrer, a jacket, a thermostated reflux column allowing the release of the alcohol released, while condensing the hydrocarbons and glycerol.
• the distillate of Example 5 is glycerolysed in the presence of 0.87 grams of glycerol and 0.01% of 50% potassium hydroxide.
• the reaction is carried out under a vacuum of 50 mbar, by heating gradually up to 200 ° C by mass. Under these conditions, in eight hours, 99% of the ethyl esters and free fatty acids initially present are converted into triglycerides.
• the product is then distilled on a column identical to that of Example 5 under a vacuum of 5 to 7 mbar and having 20 theoretical plates.
• the flow is 200 gram / hour.
• Nitrogen is injected at the bottom of the column.
• the temperature at the top of the column is 125 ° C.
• the distillate is composed of light (C8 to C15) hydrocarbons, odorous and irritating, which will be eliminated.
• the residue containing mainly hydrocarbons and triglycerides is then distilled a second time on the same equipment with a column temperature of 215 ° C.
• a distillate containing a carbon condensation hydrocarbon fraction is thus obtained, mainly from dodecane (C12) to docosan (C22). This second hydrocarbon fraction will then be mixed with the hydrocarbon fraction of Example 9 to be used during crystallization of the sterols.
• Example 1 1 - Crystallization of sterols in the presence of vegetable hydrocarbons - step c).
• the distillation residue of Example 7 has the following composition:
• This residue is diluted to room temperature in 513.6 grams of plant hydrocarbons, which corresponds to a mass ratio "bio-solvent" / residue of 4.
• the operation is carried out in a crystallizer of 1 liter, equipped with a double envelope, a stirring anchor, a temperature probe, a system for introducing inert gas (nitrogen), and a plug to put the crystallizer under vacuum.
• the medium is placed under a primary vacuum of 50 mbar and with stirring (200 rotations per minute), and then gradually heated to 80 ° C. Then progressive cooling is carried out, from 10 ° C. per hour to room temperature (25 ° C.), with gentle stirring (100 rotations per minute) to promote the development of the crystals.
• the crystals are filtered by incorporating 2% of dicalite before passing on filter press.
• the crystallization cake is well wrung, the mixture of crystals and dicalite is recovered, then melted in a small reactor, under vacuum, then refiltered in order to recover the crystals of sterols and triterpenic alcohols.
• the freezing cake can recover 84.5 grams of sterols (95% of the amount initially present before this first frigmentation). 1.1 grams of impurities, 0.2 grams of tocopherols and 1.2 grams of esters are also recovered from these crystals.
• Example 12 Second crystallization of the filtrate from the first crystallization of the sterols - step c).
• the filtrate dissolved in vegetable hydrocarbons from Example 11 containing the remainder of vitamin E (14.5 grams), sterols (4.5 grams), 1.7 grams of ethyl esters and various impurities (products of oxidative and thermal degradation, carbonyl products) is taken under the same conditions as Example 11. Then it is crystallized for 10 hours at 0 ° C. 98% of the amount of sterols present starting from Example 11 were recovered in the filter cake. The filter cake is mixed with the filter cake resulting from the first celing.
• the filtrates of the two successive crystallizations contain vitamin E, traces of esters, and impurities, all dissolved in vegetable hydrocarbons.
• This filtrate is subjected to a distillation on the reactor used in Examples 6 and 7: scraped-film thin-film evaporator, connected to a column for rectifying trays, which makes it possible to remove the residual hydrocarbons and esters.
• the column is heated to 200 ° C under a vacuum of 1 mbar.
• the system because of its thin-layer configuration, makes it possible not to degrade vitamin E.
• the residue of this first distillation is then distilled over molecular distillation.
• the evaporation chamber was maintained at 230 ° C, under a vacuum of 0.01 mbar, with stirring of 400 rotations per minute.
• the distillation makes it possible to obtain a distillate rich in vitamin E and a concentration of heavy impurities in the residue.
• the filtrate, very rich in vitamin E, but still containing impurities, can be purified according to known techniques, especially by passing on anionic resins after dissolution in bio-ethanol.

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