CA2165387A1 - Process for the selective extraction of fats and/or oils from solid natural materials - Google Patents
Process for the selective extraction of fats and/or oils from solid natural materialsInfo
- Publication number
- CA2165387A1 CA2165387A1 CA 2165387 CA2165387A CA2165387A1 CA 2165387 A1 CA2165387 A1 CA 2165387A1 CA 2165387 CA2165387 CA 2165387 CA 2165387 A CA2165387 A CA 2165387A CA 2165387 A1 CA2165387 A1 CA 2165387A1
- Authority
- CA
- Canada
- Prior art keywords
- extraction
- process according
- temperature
- pressure
- oils
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
Classifications
-
- 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
- C11B13/00—Recovery of fats, fatty oils or fatty acids from waste materials
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D11/00—Solvent extraction
- B01D11/02—Solvent extraction of solids
- B01D11/0203—Solvent extraction of solids with a supercritical fluid
-
- 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
- C11B1/00—Production of fats or fatty oils from raw materials
- C11B1/10—Production of fats or fatty oils from raw materials by extracting
-
- 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
- C11B1/00—Production of fats or fatty oils from raw materials
- C11B1/10—Production of fats or fatty oils from raw materials by extracting
- C11B1/104—Production of fats or fatty oils from raw materials by extracting using super critical gases or vapours
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
- Y02W30/00—Technologies for solid waste management
- Y02W30/50—Reuse, recycling or recovery technologies
- Y02W30/74—Recovery of fats, fatty oils, fatty acids or other fatty substances, e.g. lanolin or waxes
Abstract
The present invention provides a process for the selective extraction of fats and/or oils from solid natural materials with compressed gases, wherein the extraction is carried out with a mixture of propane and a maximum of 50% by weight of carbon dioxide at temperatures of < 96°C and pressures of < 73 bar, the two pure gases each being in the subcritical state.
Description
216~387 The present invention is concerned with a process for the selective extraction of fats and/or oils from vegetable, animal or microbial solid natural materials with a mixture of the two compressed gases propane and carbon dioxide.
In the case of extractive processes for obtaining oils and fats from natural materials, in principle liquid or gaseous solvents are used under normal conditions. Usually, on a large technical scale, extractions are frequently carried out with hexane or light benzine (petroleum ether), whereby, however, the selectivity of the processes is often not sufficient, for which reason a multi-stage refinement of the extracts must subsequently be carried out. Furthérmore, the liquid solvent must be removed not only from the extract but also from the extraction residue which, in some cases, makes necessary increased process temper-atures. In particular, when, in this way, deoiled or defatted extraction residues are to be used as starting materials for the foodstuff industry, a substantial removal of the solvent can give rise to technological problems insofar as sensitive products can thereby undergo thermal damage. An increasingly - more critical user attitude in connection with solvent residue problems in foodstuffs and also the stricter legal requirements and regulations require process improvements from the modern foodstuff technology.
From the point of view of the residue situation, extractions which use compressed gases as solvents offer decisive advantages since the actual solvent residue problem in foodstuffs (extraction residue and/or extract) can be disregarded. Of the gases unrestrictedly permitted for foodstuff technology by the present EU regulations, namely butane, carbon dioxide, propane and nitrous oxide, in particular carbon dioxide and propane are described as solvents for deoiling and defatting. Admittedly, in the case of gentle process conditions, carbon dioxide displays a very high extraction selectivity but it often only shows a satisfactory dissolving ability in the super-critical state (T >31C, p >73 bar). Especially in the case of fats and oils, as a rule a process pressure of >500 bar is necessary in order to keep the process times within technically acceptable limits (see E. Stahl, K.-W. Quirin, D. Gerard, Verdichtete Gase zur Extraktion und Raffination, pub. Springer Verlag, Berlin, 1988). Consequently, from economic points of view, in spite of many potential possibilities of using supercritical carbon dioxide, it must be considered that defatting and deoiling processes with the use of supercritical carbon dioxide are not very attractive.
In contradistinction to carbon dioxide, compressed propane shows a very good dissolving ability for lipophilic materials, even in the case of a very much lower process pressure (<50 bar). This advantage has already been described for quite a long time in the case of the gas extraction of fats and oils, for example in U.S. Patent Specifications Nos. 2,254,245;
In the case of extractive processes for obtaining oils and fats from natural materials, in principle liquid or gaseous solvents are used under normal conditions. Usually, on a large technical scale, extractions are frequently carried out with hexane or light benzine (petroleum ether), whereby, however, the selectivity of the processes is often not sufficient, for which reason a multi-stage refinement of the extracts must subsequently be carried out. Furthérmore, the liquid solvent must be removed not only from the extract but also from the extraction residue which, in some cases, makes necessary increased process temper-atures. In particular, when, in this way, deoiled or defatted extraction residues are to be used as starting materials for the foodstuff industry, a substantial removal of the solvent can give rise to technological problems insofar as sensitive products can thereby undergo thermal damage. An increasingly - more critical user attitude in connection with solvent residue problems in foodstuffs and also the stricter legal requirements and regulations require process improvements from the modern foodstuff technology.
From the point of view of the residue situation, extractions which use compressed gases as solvents offer decisive advantages since the actual solvent residue problem in foodstuffs (extraction residue and/or extract) can be disregarded. Of the gases unrestrictedly permitted for foodstuff technology by the present EU regulations, namely butane, carbon dioxide, propane and nitrous oxide, in particular carbon dioxide and propane are described as solvents for deoiling and defatting. Admittedly, in the case of gentle process conditions, carbon dioxide displays a very high extraction selectivity but it often only shows a satisfactory dissolving ability in the super-critical state (T >31C, p >73 bar). Especially in the case of fats and oils, as a rule a process pressure of >500 bar is necessary in order to keep the process times within technically acceptable limits (see E. Stahl, K.-W. Quirin, D. Gerard, Verdichtete Gase zur Extraktion und Raffination, pub. Springer Verlag, Berlin, 1988). Consequently, from economic points of view, in spite of many potential possibilities of using supercritical carbon dioxide, it must be considered that defatting and deoiling processes with the use of supercritical carbon dioxide are not very attractive.
In contradistinction to carbon dioxide, compressed propane shows a very good dissolving ability for lipophilic materials, even in the case of a very much lower process pressure (<50 bar). This advantage has already been described for quite a long time in the case of the gas extraction of fats and oils, for example in U.S. Patent Specifications Nos. 2,254,245;
2,560,935; 2,548,434 and 2,682,551, as well as also in U.S. Patent Specification No. 4,331,695. However, a serious disadvantage of compressed propane as extraction solvent is generally its lower selectivity in comparison with carbon dioxide, which is especially manifested in the undesired co-extraction of accompanying materials, for example coloured materials and phospholipids. Additionally, by careful choice of the process parameters, the selectivity of the propane extraction can be increased (cf. DE 43 26 399 Al) but this is not sufficient for numerous uses so that the extracted fats and oils must be further worked up and refined.
According to DE 34 29 416 Al, with a process for the extraction of oil from oil-containing vegetable materials, an attempt was made to improve the low dissolving capacity of supercritical carbon dioxide for vegetable oils by feeding a supercritical entraining agent, for example propane or butane, into the extraction. With this process variant, it is admittedly possible distinctly to improve the solubility for oil in comparison with pure carbon dioxide but the necessary process pressures must still 216~387 be from 80 to 300 bar in order to keep the carbon dioxide in the supercritical state. Furthermore, the specific gas throughput rates necessary for the achievement of the object of the extraction are still very high so that a long and thus uneconomic extraction time must be taken into account.
Thus, it is an object of the present invention to overcome the disadvantages of the known processes with the help of a process for the selective extraction of fats and/or oils from solid natural materials and to provide an economic process with improved selectivity for obtaining fats and/or oils with the use of compressed gases. Furthermore, in general, gentle process conditions are to be achieved with regard to a good product quality and especially a lower process pressure and a favourable specific gas throughput rate.
Thus, according to the present invention, there is provided a process for the selective extraction of fats and/or oils from solid natural materials, wherein the extraction is carried out with a mixture of propane and a maximum of 50% by weight carbon dioxide at temperatures of <96C and pressures of <73 bar, the two pure gases each being present in the subcritical state.
Surprisingly, we have found that the gas mixture under these conditions possesses, on the one hand, a very high dissolving ability for oils and fats (in 216~387 comparison with pure compressed propane) but, at the same time, displays the dissolving selectivity of supercritical carbon dioxide. However, the favourable process pressure can thereby be maintained similarly to the extraction with pure propane. In contra-distinction to the earlier processes, in the case of the process according to the present invention, the proportion of compressed carbon dioxide, which is always selected at ~ 50% by weight, can be regarded as being a "selectivity modulator" with which a surprisingly high increase of selectivity can be achieved.
Thus, the process according to the present invention combines the decisive advantages of gas extraction with supercritical carbon dioxide (high extraction selectivity) and compressed propane (high dissolving ability in the case of low process pressure) without displaying their disadvantages.
As already mentioned, in the case of the extraction of fats and oils from natural materials, depending upon the selectivity of the process, a number of undesired accompanying materials are also co-extracted which, in the case of the known processes, must often have to be separated off in subsequent process steps in order to achieve a good product quality. Typical fat accompanying materials include, for example, phospholipids (lecithins), coloured ~ 2165~87 materials and waxes. In the case of the process according to the present invention, by the addition of carbon dioxide to compressed propane, the undesired co-extraction of these materials can be suppressed in a targeted manner, whereby essentially the composition of the starting material and the quality of the product to be achieved determines the proportion of the carbon dioxide.
Amounts of carbon dioxide are preferably between 20 and 40% by weight, whereby, in this case, the process pressure is from 25 to 40 bar and an extraction temperature of <50C is selected. Thus, for example, in the case of the deoiling of soya flakes, in the case of a proportion of 10% by weight of carbon dioxide, a recognisable decrease of the phospholipids in the extracted soya oil is ascertained. In the case of a carbon dioxide content from about 40% by weight, a highly deslimed soya oil can be obtained which has a total phosphorus content of < 5 ppm. In addition, the increase of the selectivity of the extraction is to be very well recognised by the optical advantages in the form of a distinctly clearer colour of the oil obtained.
The amount of gas needed for the extraction can be varied within a relatively wide range and depends essentially upon the starting material of the gas composition and the desired aim of the extraction.
Typical extraction amounts are from 1 to 10 g of - ~165~87 extraction mixture for 1 g of oil or fat to be extracted.
The process according to the present invention is very well suited for the extraction of sensitive natural materials since it can be carried out under process conditions which are very gentle for the product. Important for the process is the fact that it is always carried out at extraction temperatures of < 96C (the critical temperature of propane) and extraction pressures of < 73 bar (the critical pressure of carbon dioxide). Under these conditions, the two pure gases are subcritical (propane: Tc = 96C, Pc =
42 bar; carbon dioxide: Tc = 31C, Pc = 73 bar).
Especially in the case of the extraction of temperature-sensitive natural materials, a process temperature of< 60C is preferably selected in order to avoid thermal damage of special component materials, for example of highly unsaturated fatty acids or proteins. Considered generally, in the case of an extraction temperature predetermined by the process, only such an extraction temperature is necessary which keeps the gas mixture in a liquid state; however, it must not exceed 73 bar, the critical pressure of carbon dioxide.
After the extraction, the extracted fats and/or oils are separated off from the extraction mixture by increasing the temperature and/or lowering the pressure since, under such changed conditions, the dissolving 216~387 g ability of the gas mixture is very considerably decreased. The extent of the temperature increase and/or of the pressure lowering depends very consider-ably upon the selected composition of the gas mixture which is used for the extraction in question.
Process technically, two possibilities are preferred for the separation of the extracts:
(i) The pressure and/or the temperature are decreased or increased, respectively, in an extract separator to such an extent that the gas mixture is completely converted into the gaseous phase. On the basis of the low solubility of the extracts in the gas phase, as a result these are separated out from the gaseous mixture.
In a preferred embodiment, for the minimisation of the thermal stressing of the extracts, the separation temperature is kept at < 60C. Depending upon the composition of the extraction mixture, the pressure in the separator is then from 8 to 30 bar.
(ii) Especially in the case of low proportions of carbon dioxide in the extraction mixture, the reverse dissolving ability of propane in the region of the critical state can be utilised, i.e. the extraction mixture is not converted into the gaseous state but rather, starting from the liquid state in the case of the extraction, is brought into the region of the critical state in the case of the extract separation, whereby the dissolving ability for fats and oils can - 216~3~7 - 1 o -be very greatly reduced. However, in contradistinction to the first-mentioned possibility, the second one is less temperature gentle since, according to a preferred variant, in the case of proportions of carbon dioxide of < 20% by weight, it is necessary to work with separation temperatures in the range of 90 to 100C, i.e. in the region of the critical temperature of propane (Tc = 96C), and at a separation pressure which is from 42 to 80 bar.
In the case of a preferred embodiment of the process according to the present invention, the extraction gas mixture is recovered directly in an extraction plant after separation of the extracts in an extract separator, again adjusted to the extraction state and then returned to the extraction process (cyclic process). Thus, due to the low extraction pressure and the favourable solvent requirement, with the process according to the present invention there can be carried out a selective gas extraction of fats and oils with distinctly improved economy than hitherto.
Quite generally, the process according to the present invention can be used advantageously for work-ing up numerous sensitive natural materials. There can thereby be used all solid starting materials of vegetable, microbial and animal origin which are also otherwise used for obtaining oils and fats. Examples from the field of vegetable starting materials include 2165~87 seeds, such as soya beans and rape seed, and plant seedlings, such as wheat germ. As microbial starting materials, there can be used, for example, dried fermentation residues which have a high content of desired lipid components. As products of animal origin, there can be mentioned, for example, wool from which wool fat (lanolin) can be obtained in very good quality.
The following Examples are given for the purpose of illustrating the present invention, whereby, in particular, the targeted control of the selectivity properties is illustrated.
Examples Examples 1 to 6 describe the use of the process according to the present invention in the case of soya as vegetable starting material.
In a high pressure extraction plant, in an extraction autoclave with a volume of 4 1 were, in each case, introduced 1.7 kg of flaked soya beans (oil content 21.0%) and in each case extracted at an extraction temperature of 40C under the conditions given in the following Table 1. With the particular given specific gas throughput, there was achieved the corresponding extraction yield. The analysis of the total phosphorus took place X-ray fluorimetrically.
~16~ 387 P.-- ^
~ ~ u~o ~ ~ a~
~ v ~ 3 o~
o .. . . . . U~
o o o o ~ ~ ~ a --, C; n t~ 1 ~
r- .~0~ 00 00 U~ - ~
O
'~ ~
O
~ ~ ~ 3 ~
a~ ~o o o o o o a~ ~
a~ C ~ ~ ~ ~ u~
E~ I 1 J 3 o ~c~ o o ~ o ~ o a~
L ~ Ul ~ I C~) ~ ~ ~, a~
~ C
C 1^
, ~ o u. ~ o o ~ 8 rl a o o o U: I
O O O O O L~
~L I ~C~ ~ ~ O
O O O O O O L~ --O ~oo 1~~ U~
,~ C
a a~
C r ~1 ~
. ~ a~
a~ ~ a, ~ C~ ~ o C) ~Zo ~ C~
Examples 7 to 11 describe the process in the case of the extraction of oils from dried fermentation residues for obtaining PUFA-rich oils (PUFA = poly-unsaturated fatty acids).
The starting material was a dried fermentation residue (water content ~ 5%) which was pelleted (pellet size about 2 mm). At the beginning of the extraction, the total oil content was 46% by weight.
The starting material was introduced in amounts of, in each case, 0.5 kg into a high pressure extraction plant with an autoclave volume of about 1 1. In each case, the extraction temperature was 40C.
- 216S~87 ~, _ _ $ o o ,~ ~ o oo C~
J J~
J
n ~n ~ ~
_ ,~ o ~ ~ a ~ ' ~ s o o o o o 1 ~
~ - X
a~
o ~
~ ~ o o o o o ~n a~ .C ~ ~ U~ u- ~ ~ ~ ~ ,n ,D ~ _, ~
u~ L ~ n ~ ~ oo ~ ~ o ~
~ ~ ~ '~ '~ ~ 3 ~1 c~ o - - - ~
r ,~, ~d O U~ o o o u:
~ r~
i ~ a ~
O ~r ~e O O O O _ .
~ o o o o o -1, 3 0 ~ 00 1~ ~O ~, C,~
5 -~3 ~ ~ o C r~
' !: C a) ~ 5 H C,~ ~
~ 0 1-- ~ 00 ~ O .~
~16~387 Examples 12 and 13 describe the advantages of the process according to the present invention in the case of the extraction of wool fat from sheep wool (starting material of animal origin).
For this purpose, in each case into the 4 1 auto-clave of a high pressure extraction plant were introduced 1 kg of raw wool tamount of wool fat 11.5% by weight as dichloromethane-extractable proportion) and in each case extracted at 40C under the conditions given in the following Table 3 with the given results.
Table 3 Examp-e propane/CO2 extraction separation specific gas extract colour of the No. (wt.-%) pressure pressure temper- throughput yield extracted (bar) (bar) ature (C) (kg/kg starting (wt.-%) wool fat material ) 12 100/0 20 8 50 5 8.5 dark brown (comparison) 13 60/40 55 25 50 8 7.3 bright yellow CJ~
C~3 oo
According to DE 34 29 416 Al, with a process for the extraction of oil from oil-containing vegetable materials, an attempt was made to improve the low dissolving capacity of supercritical carbon dioxide for vegetable oils by feeding a supercritical entraining agent, for example propane or butane, into the extraction. With this process variant, it is admittedly possible distinctly to improve the solubility for oil in comparison with pure carbon dioxide but the necessary process pressures must still 216~387 be from 80 to 300 bar in order to keep the carbon dioxide in the supercritical state. Furthermore, the specific gas throughput rates necessary for the achievement of the object of the extraction are still very high so that a long and thus uneconomic extraction time must be taken into account.
Thus, it is an object of the present invention to overcome the disadvantages of the known processes with the help of a process for the selective extraction of fats and/or oils from solid natural materials and to provide an economic process with improved selectivity for obtaining fats and/or oils with the use of compressed gases. Furthermore, in general, gentle process conditions are to be achieved with regard to a good product quality and especially a lower process pressure and a favourable specific gas throughput rate.
Thus, according to the present invention, there is provided a process for the selective extraction of fats and/or oils from solid natural materials, wherein the extraction is carried out with a mixture of propane and a maximum of 50% by weight carbon dioxide at temperatures of <96C and pressures of <73 bar, the two pure gases each being present in the subcritical state.
Surprisingly, we have found that the gas mixture under these conditions possesses, on the one hand, a very high dissolving ability for oils and fats (in 216~387 comparison with pure compressed propane) but, at the same time, displays the dissolving selectivity of supercritical carbon dioxide. However, the favourable process pressure can thereby be maintained similarly to the extraction with pure propane. In contra-distinction to the earlier processes, in the case of the process according to the present invention, the proportion of compressed carbon dioxide, which is always selected at ~ 50% by weight, can be regarded as being a "selectivity modulator" with which a surprisingly high increase of selectivity can be achieved.
Thus, the process according to the present invention combines the decisive advantages of gas extraction with supercritical carbon dioxide (high extraction selectivity) and compressed propane (high dissolving ability in the case of low process pressure) without displaying their disadvantages.
As already mentioned, in the case of the extraction of fats and oils from natural materials, depending upon the selectivity of the process, a number of undesired accompanying materials are also co-extracted which, in the case of the known processes, must often have to be separated off in subsequent process steps in order to achieve a good product quality. Typical fat accompanying materials include, for example, phospholipids (lecithins), coloured ~ 2165~87 materials and waxes. In the case of the process according to the present invention, by the addition of carbon dioxide to compressed propane, the undesired co-extraction of these materials can be suppressed in a targeted manner, whereby essentially the composition of the starting material and the quality of the product to be achieved determines the proportion of the carbon dioxide.
Amounts of carbon dioxide are preferably between 20 and 40% by weight, whereby, in this case, the process pressure is from 25 to 40 bar and an extraction temperature of <50C is selected. Thus, for example, in the case of the deoiling of soya flakes, in the case of a proportion of 10% by weight of carbon dioxide, a recognisable decrease of the phospholipids in the extracted soya oil is ascertained. In the case of a carbon dioxide content from about 40% by weight, a highly deslimed soya oil can be obtained which has a total phosphorus content of < 5 ppm. In addition, the increase of the selectivity of the extraction is to be very well recognised by the optical advantages in the form of a distinctly clearer colour of the oil obtained.
The amount of gas needed for the extraction can be varied within a relatively wide range and depends essentially upon the starting material of the gas composition and the desired aim of the extraction.
Typical extraction amounts are from 1 to 10 g of - ~165~87 extraction mixture for 1 g of oil or fat to be extracted.
The process according to the present invention is very well suited for the extraction of sensitive natural materials since it can be carried out under process conditions which are very gentle for the product. Important for the process is the fact that it is always carried out at extraction temperatures of < 96C (the critical temperature of propane) and extraction pressures of < 73 bar (the critical pressure of carbon dioxide). Under these conditions, the two pure gases are subcritical (propane: Tc = 96C, Pc =
42 bar; carbon dioxide: Tc = 31C, Pc = 73 bar).
Especially in the case of the extraction of temperature-sensitive natural materials, a process temperature of< 60C is preferably selected in order to avoid thermal damage of special component materials, for example of highly unsaturated fatty acids or proteins. Considered generally, in the case of an extraction temperature predetermined by the process, only such an extraction temperature is necessary which keeps the gas mixture in a liquid state; however, it must not exceed 73 bar, the critical pressure of carbon dioxide.
After the extraction, the extracted fats and/or oils are separated off from the extraction mixture by increasing the temperature and/or lowering the pressure since, under such changed conditions, the dissolving 216~387 g ability of the gas mixture is very considerably decreased. The extent of the temperature increase and/or of the pressure lowering depends very consider-ably upon the selected composition of the gas mixture which is used for the extraction in question.
Process technically, two possibilities are preferred for the separation of the extracts:
(i) The pressure and/or the temperature are decreased or increased, respectively, in an extract separator to such an extent that the gas mixture is completely converted into the gaseous phase. On the basis of the low solubility of the extracts in the gas phase, as a result these are separated out from the gaseous mixture.
In a preferred embodiment, for the minimisation of the thermal stressing of the extracts, the separation temperature is kept at < 60C. Depending upon the composition of the extraction mixture, the pressure in the separator is then from 8 to 30 bar.
(ii) Especially in the case of low proportions of carbon dioxide in the extraction mixture, the reverse dissolving ability of propane in the region of the critical state can be utilised, i.e. the extraction mixture is not converted into the gaseous state but rather, starting from the liquid state in the case of the extraction, is brought into the region of the critical state in the case of the extract separation, whereby the dissolving ability for fats and oils can - 216~3~7 - 1 o -be very greatly reduced. However, in contradistinction to the first-mentioned possibility, the second one is less temperature gentle since, according to a preferred variant, in the case of proportions of carbon dioxide of < 20% by weight, it is necessary to work with separation temperatures in the range of 90 to 100C, i.e. in the region of the critical temperature of propane (Tc = 96C), and at a separation pressure which is from 42 to 80 bar.
In the case of a preferred embodiment of the process according to the present invention, the extraction gas mixture is recovered directly in an extraction plant after separation of the extracts in an extract separator, again adjusted to the extraction state and then returned to the extraction process (cyclic process). Thus, due to the low extraction pressure and the favourable solvent requirement, with the process according to the present invention there can be carried out a selective gas extraction of fats and oils with distinctly improved economy than hitherto.
Quite generally, the process according to the present invention can be used advantageously for work-ing up numerous sensitive natural materials. There can thereby be used all solid starting materials of vegetable, microbial and animal origin which are also otherwise used for obtaining oils and fats. Examples from the field of vegetable starting materials include 2165~87 seeds, such as soya beans and rape seed, and plant seedlings, such as wheat germ. As microbial starting materials, there can be used, for example, dried fermentation residues which have a high content of desired lipid components. As products of animal origin, there can be mentioned, for example, wool from which wool fat (lanolin) can be obtained in very good quality.
The following Examples are given for the purpose of illustrating the present invention, whereby, in particular, the targeted control of the selectivity properties is illustrated.
Examples Examples 1 to 6 describe the use of the process according to the present invention in the case of soya as vegetable starting material.
In a high pressure extraction plant, in an extraction autoclave with a volume of 4 1 were, in each case, introduced 1.7 kg of flaked soya beans (oil content 21.0%) and in each case extracted at an extraction temperature of 40C under the conditions given in the following Table 1. With the particular given specific gas throughput, there was achieved the corresponding extraction yield. The analysis of the total phosphorus took place X-ray fluorimetrically.
~16~ 387 P.-- ^
~ ~ u~o ~ ~ a~
~ v ~ 3 o~
o .. . . . . U~
o o o o ~ ~ ~ a --, C; n t~ 1 ~
r- .~0~ 00 00 U~ - ~
O
'~ ~
O
~ ~ ~ 3 ~
a~ ~o o o o o o a~ ~
a~ C ~ ~ ~ ~ u~
E~ I 1 J 3 o ~c~ o o ~ o ~ o a~
L ~ Ul ~ I C~) ~ ~ ~, a~
~ C
C 1^
, ~ o u. ~ o o ~ 8 rl a o o o U: I
O O O O O L~
~L I ~C~ ~ ~ O
O O O O O O L~ --O ~oo 1~~ U~
,~ C
a a~
C r ~1 ~
. ~ a~
a~ ~ a, ~ C~ ~ o C) ~Zo ~ C~
Examples 7 to 11 describe the process in the case of the extraction of oils from dried fermentation residues for obtaining PUFA-rich oils (PUFA = poly-unsaturated fatty acids).
The starting material was a dried fermentation residue (water content ~ 5%) which was pelleted (pellet size about 2 mm). At the beginning of the extraction, the total oil content was 46% by weight.
The starting material was introduced in amounts of, in each case, 0.5 kg into a high pressure extraction plant with an autoclave volume of about 1 1. In each case, the extraction temperature was 40C.
- 216S~87 ~, _ _ $ o o ,~ ~ o oo C~
J J~
J
n ~n ~ ~
_ ,~ o ~ ~ a ~ ' ~ s o o o o o 1 ~
~ - X
a~
o ~
~ ~ o o o o o ~n a~ .C ~ ~ U~ u- ~ ~ ~ ~ ,n ,D ~ _, ~
u~ L ~ n ~ ~ oo ~ ~ o ~
~ ~ ~ '~ '~ ~ 3 ~1 c~ o - - - ~
r ,~, ~d O U~ o o o u:
~ r~
i ~ a ~
O ~r ~e O O O O _ .
~ o o o o o -1, 3 0 ~ 00 1~ ~O ~, C,~
5 -~3 ~ ~ o C r~
' !: C a) ~ 5 H C,~ ~
~ 0 1-- ~ 00 ~ O .~
~16~387 Examples 12 and 13 describe the advantages of the process according to the present invention in the case of the extraction of wool fat from sheep wool (starting material of animal origin).
For this purpose, in each case into the 4 1 auto-clave of a high pressure extraction plant were introduced 1 kg of raw wool tamount of wool fat 11.5% by weight as dichloromethane-extractable proportion) and in each case extracted at 40C under the conditions given in the following Table 3 with the given results.
Table 3 Examp-e propane/CO2 extraction separation specific gas extract colour of the No. (wt.-%) pressure pressure temper- throughput yield extracted (bar) (bar) ature (C) (kg/kg starting (wt.-%) wool fat material ) 12 100/0 20 8 50 5 8.5 dark brown (comparison) 13 60/40 55 25 50 8 7.3 bright yellow CJ~
C~3 oo
Claims (14)
1. A process for the selective extraction of at least one of fats and oils from solid natural materials with compressed gases, wherein the extraction is carried out with a gas mixture of propane and a maximum of 50% by weight of carbon dioxide at a temperature of < 96°C and pressure of < 73 bar, the two pure gases each being in the subcritical state.
2. A process according to claim 1, wherein the proportion of carbon dioxide in the gas mixture is from 20 to 40% by weight.
3. A process according to claim 1, wherein the temperature is < 50°C and the pressure is from 25 to 45 bar.
4. A process according to claim 2, wherein the temperature is < 50°C and the pressure is from 25 to 45 bar.
5. A process according to claim 1, 2, 3 or 4, wherein 1 to 10 g of the propane/carbon dioxide mixture is used per gram of the at least one of fats and oils to be extracted.
6. A process according to claim 1, 2, 3 or 4, wherein the at least one of fats and oils are separated from the gas mixture by at least one of:
a) increasing the temperature, and b) lowering the pressure.
a) increasing the temperature, and b) lowering the pressure.
7. A process according to claim 5, wherein the at least one of fats and oils are separated from the gas mixture by at least one of:
a) increasing the temperature, and b) lowering the pressure.
a) increasing the temperature, and b) lowering the pressure.
8. A process according to claim 6, wherein the separating is at a temperature of < 60°C and the separating is at a pressure of from 8 to 30 bar.
9. A process according to claim 7, wherein the separating is at a temperature of < 60°C and the separating is at a pressure of from 8 to 30 bar.
10. A process according to claim 1, 2, 3, 4, 7, 8 or 9, wherein said natural materials are temperature-sensitive and the process temperature is < 60°C.
11. A process according to claim 6, wherein the carbon dioxide is in a proportion of < 20% by weight and the separating is at a temperature adjusted to 90 to 100°C and a pressure adjusted to 42 to 80 bar.
12. A process according to claim 7, wherein the carbon dioxide is in a proportion of < 20% by weight and the separating is at a temperature adjusted to 90 to 100°C and a pressure adjusted to 42 to 80 bar.
13. A process according to claim 1, 2, 3, 4, 7, 8, 9, 11 or 12, wherein soya beans, rape, plant seedlings, fermentation residues or wool are extracted.
14. Fats and oils whenever obtained from solid natural materials by the process according to claim 1, 2, 3, 4, 7, 8, 9, 11 or 12.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE4445134 | 1994-12-17 | ||
| DEP4445134.2 | 1994-12-17 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2165387A1 true CA2165387A1 (en) | 1996-06-18 |
Family
ID=6536161
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA 2165387 Abandoned CA2165387A1 (en) | 1994-12-17 | 1995-12-15 | Process for the selective extraction of fats and/or oils from solid natural materials |
Country Status (5)
| Country | Link |
|---|---|
| EP (1) | EP0721980A3 (en) |
| JP (1) | JPH08218088A (en) |
| CA (1) | CA2165387A1 (en) |
| FI (1) | FI956044A0 (en) |
| NO (1) | NO955076D0 (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6066350A (en) * | 1997-02-07 | 2000-05-23 | Cargill Incorporated | Method and arrangement for processing cocoa mass |
| US7201934B2 (en) | 2002-10-15 | 2007-04-10 | Cargill, Incorporated | Dispersible cocoa products |
| EP2450424A1 (en) | 2010-11-08 | 2012-05-09 | Neste Oil Oyj | A method for recovery of oil from biomass |
Families Citing this family (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE19719431A1 (en) * | 1997-05-12 | 1998-11-19 | Degussa | Process for the continuous catalytic conversion of organic compounds |
| GB2391865B (en) * | 2002-08-14 | 2005-06-01 | Gw Pharma Ltd | Improvements in the extraction of pharmaceutically active components from plant materials |
| DE102005037209A1 (en) * | 2005-08-06 | 2007-02-08 | Degussa Ag | Process for the extraction of natural oils from plant constituents |
| FR2917422A1 (en) * | 2007-06-14 | 2008-12-19 | Air Liquide | Extraction of plant oil from extraction material e.g. oil producing seeds, where sub-critical carbon dioxide is used as a solvent throughout or part of the extraction, useful for the preparation of biodiesel |
| WO2012071972A1 (en) * | 2010-11-30 | 2012-06-07 | 新奥科技发展有限公司 | Process for extracting oil and fat from microalgae |
| WO2017041776A1 (en) | 2015-09-11 | 2017-03-16 | B+B Engineering Gmbh | Method of combined cell digestion and extraction of oil-containing seeds |
| EP3165099A1 (en) | 2015-11-03 | 2017-05-10 | Evonik Degussa GmbH | Removing oil and simultaneous removal of unwanted contaminants from beans with supercritical co2 |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| AT331374B (en) * | 1972-12-22 | 1976-08-25 | Studiengesellschaft Kohle Mbh | PROCESS FOR THE PRODUCTION OF FATS AND OILS FROM VEGETABLE AND ANIMAL PRODUCTS |
| DE3429416A1 (en) * | 1984-08-09 | 1986-02-20 | Siegfried Prof.Dr. 8520 Erlangen Peter | METHOD FOR THE EXTRACTION OF OIL FROM OIL-BASED VEGETABLE SUBSTANCES |
| US5281732A (en) * | 1991-12-31 | 1994-01-25 | University Research & Marketing | Solvent extraction of oil from oil-bearing materials |
-
1995
- 1995-12-14 NO NO955076A patent/NO955076D0/en unknown
- 1995-12-15 FI FI956044A patent/FI956044A0/en unknown
- 1995-12-15 EP EP19950119848 patent/EP0721980A3/en not_active Withdrawn
- 1995-12-15 CA CA 2165387 patent/CA2165387A1/en not_active Abandoned
- 1995-12-15 JP JP32734295A patent/JPH08218088A/en active Pending
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6066350A (en) * | 1997-02-07 | 2000-05-23 | Cargill Incorporated | Method and arrangement for processing cocoa mass |
| US6361814B2 (en) | 1997-02-07 | 2002-03-26 | Cargill Incorporated | Method and arrangement for processing cocoa mass; resulting products |
| US6610343B2 (en) | 1997-02-07 | 2003-08-26 | Cargill, Incorporated | Method for processing cocoa mass |
| US7709041B2 (en) | 1997-02-07 | 2010-05-04 | Cargill, Incorporated | Low-fat cocoa powder |
| US7201934B2 (en) | 2002-10-15 | 2007-04-10 | Cargill, Incorporated | Dispersible cocoa products |
| EP2450424A1 (en) | 2010-11-08 | 2012-05-09 | Neste Oil Oyj | A method for recovery of oil from biomass |
| WO2012062961A1 (en) * | 2010-11-08 | 2012-05-18 | Neste Oil Oyj | A method for recovery of oil from biomass |
| US9868922B2 (en) | 2010-11-08 | 2018-01-16 | Neste Oyj | Method for recovery of oil from biomass |
Also Published As
| Publication number | Publication date |
|---|---|
| EP0721980A2 (en) | 1996-07-17 |
| FI956044A0 (en) | 1995-12-15 |
| NO955076D0 (en) | 1995-12-14 |
| JPH08218088A (en) | 1996-08-27 |
| EP0721980A3 (en) | 1997-10-22 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Friedrich et al. | Characterization of soybean oil extracted by supercritical carbon dioxide and hexane | |
| Friedrich et al. | Supercritical CO2 extraction of lipid‐bearing materials and characterization of the products | |
| RU2062295C1 (en) | Method for extraction of fats and oils of natural material | |
| Chan et al. | Supercritical carbon dioxide fluid extraction of Hibiscus cannabinus L. seed oil: a potential solvent-free and high antioxidative edible oil | |
| US3966981A (en) | Process for removing residual solvents | |
| US5718937A (en) | Process for the extraction of natural aromas from natural substances containing fat and oil | |
| US5626756A (en) | Process for fractionating and refining natural lipid substances | |
| CA1320948C (en) | Separation of sterols from lipids | |
| CA2165387A1 (en) | Process for the selective extraction of fats and/or oils from solid natural materials | |
| US4548755A (en) | Process for the extractive production of valuable natural waxes | |
| EP0616821A1 (en) | Fragrance extraction | |
| AU756898B2 (en) | Method for eliminating free fatty acids from fats and oils of biological origin or their vapor condensates | |
| CA1133515A (en) | Preparation of hop extracts rich in particular constituents | |
| Dobarganes Nodar et al. | Characterisation and process development of supercritical fluid extraction of soybean oil | |
| Salgın et al. | Supercritical fluid extraction of walnut kernel oil | |
| CA2118894A1 (en) | Process for the production of egg-based products in a powder form with a reduced fat and cholesterol content | |
| Nagao et al. | Lipid of sunflower seeds produced in Japan | |
| KR20080038205A (en) | Method for obtaining natural oils from plant constituents | |
| GB2173985A (en) | Extraction of aroma materials | |
| US2377975A (en) | Method of solvent extraction of oil from seeds | |
| Ortiz et al. | Extraction of alkaloids and oil from bitter lupin seed | |
| Mangold | Liquefied gases and supercritical fluids in oilseed extraction | |
| Mangold | Extraction with supercritical fluids: A progress report from Germany | |
| Brannolte et al. | Effects of pressure and temperature of supercritical carbon dioxide on the extraction of triacylglycerols from plant tissue | |
| EP3766950B1 (en) | Method for the separate extraction of rice bran oil and rice bran waxes |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| FZDE | Dead |