Method for reducing content of saturated hydrocarbon, and refined palm-based oils and/or fats

Abstract

A method for reducing the content of a saturated hydrocarbon in oils and/or fats. The method includes subjecting raw material oils and/or fats to a short path distillation treatment under a temperature condition of 50° C. or higher and 270° C. or lower. In the short path distillation treatment, a feed rate of the raw material oils and/or fats to a short path distillation apparatus may be 30.0 kg/h.Math.m.sup.2 or less per unit area of an evaporation surface of the short path distillation apparatus. The feed rate may be 5.00 kg/h.Math.m.sup.2 or more and 25.0 kg/h.Math.m.sup.2 or less per unit area of an evaporation surface of the short path distillation apparatus.

Claims

1. A method for reducing a content of all C20-C35 saturated hydrocarbons in raw material oils and/or fats, to produce refined oils and/or fats, the method comprising subjecting raw material oils and/or fats to a short path distillation treatment at a temperature of 200° C. or higher to reduce the content of all C20-C35 saturated hydrocarbons from the oils and/or fats, wherein, in the short path distillation treatment, a feed rate of the raw material oils and/or fats to a short path distillation apparatus is 8.3 to 25.0 kg/h.Math.m.sup.2 per unit area of an evaporation surface of the short path distillation apparatus, wherein the raw material oils and/or fats are palm-based oils and/or fats, wherein a degree of vacuum in the short path distillation treatment is 0.05 Pa, and wherein the content of all C20-C35 saturated hydrocarbons is reduced to less than 2 mg/kg.

2. The method according to claim 1, wherein the feed rate is 8.3 kg/h.Math.m.sup.2 per unit area of the evaporation surface of the short path distillation apparatus.

3. The method according to claim 1, wherein an upper limit of the temperature in the short path distillation treatment is 200° C., and the feed rate of the raw material oils and/or fats to the short path distillation apparatus is 8.3 to 25.0 kg/h.Math.m.sup.2 per unit area of an evaporation surface of the short path distillation apparatus.

4. The method according to claim 1, wherein an upper limit of the temperature in the short path distillation treatment is 200° C., and the feed rate of the raw material oils and/or fats to the short path distillation apparatus is 8.3 kg/h.Math.m.sup.2 per unit area of an evaporation surface of the short path distillation apparatus.

5. The method according to claim 1, wherein the short path distillation treatment is performed two times or more.

Description

EXAMPLES

(1) The present invention will be specifically described below by way of Examples, but the present invention is not limited to these Examples.

(2) <Test 1: Study on Various Conditions in Short Path Distillation Treatment>

(3) Raw material palm-based oils and/or fats (which are RBD palm oils and correspond to raw material oils and/or fats) were injected into an evaporation surface of a short path distillation apparatus, Model KDL6 (manufactured by UIC GmbH, evaporation surface made of stainless steel: 600 cm.sup.2, condensation surface: 600 cm.sup.2, maximum flow rate: 3 to 10 L/hour) and then a short path distillation treatment was performed under the conditions shown in Table 1. The retention time of raw material palm-based oils and/or fats on the evaporation surface of the short path distillation apparatus (in other words, treatment time of short path distillation treatment) was set at 1 second or more and 30 seconds or less.

(4) After the short path distillation treatment under the above conditions, a residual fraction and a distillation fraction were collected. In Table 1, “distillation fraction ratio” means a proportion of the distillation fraction in the total amount of the thus collected residual fraction and distillation fraction. The lower the distillation fraction ratio, the higher a yield becomes.

(5) Regarding raw material palm-based oils and/or fats before a short path distillation treatment, and a residual fraction after the short path distillation treatment (which corresponds to refined oils and/or fats), physical properties and composition were studied as follows. The results are shown in Table 1.

(6) [Color]

(7) Color (Y value, R value) was measured in accordance with “2.2.1-1996 Lovibond Method in “Standard Methods for the Analysis of Fats, Oils and Related Materials” edited by Japan Oil Chemists' Society”. In the measurement, Lovibond colorimeter (cell length: 133.4 mm) was used.

(8) [Acid Value]

(9) An acid value was measured in accordance with “2.3.1-1996 Acid Value in “Standard Methods for the Analysis of Fats, Oils and Related Materials” edited by Japan Oil Chemists' Society”.

(10) [Peroxide Value]

(11) A peroxide value was measured in accordance with “2.5.2.1-2013 Peroxide Value in “Standard Methods for the Analysis of Fats, Oils and Related Materials” edited by Japan Oil Chemists' Society”

(12) [Conductometric Determination Method (CDM)]

(13) Conductometric Determination Method (CDM) was measured in accordance with “2.5.1.2-1996 in “Standard Methods for the Analysis of Fats, Oils and Related Materials” edited by Japan Oil Chemists' Society”. The higher the measured value of CDM, the more oils and/or fats are autoxidated.

(14) [Melting Point(Slipping Point)]

(15) A Melting point (Slipping Point) was measured in accordance with “2.2.4.2-1996 in “Standard Methods for the Analysis of Fats, Oils and Related Materials” edited by Japan Oil Chemists' Society”.

(16) [Determination of Saturated Hydrocarbon Content]

(17) The content of a saturated hydrocarbon was measured in accordance with the following method.

(18) (1) To 200 mg of each of oil and/or fat samples, 3 ppm of an internal standard material (bicyclohexyl) was added, followed by dissolution with 1 mL of hexane.

(19) (2) In a 2 g of a silica solid-phase extraction column conditioned with hexane, the sample in (1) was charged and then adsorbed.

(20) (3) A saturated hydrocarbon was eluted with hexane from the column in (2). After disposing 1 mL of the saturated hydrocarbon eluted initially, 3 mL of the saturated hydrocarbon eluted subsequently was recovered, thus obtaining a saturated hydrocarbon fraction.
(4) After concentrating the saturated hydrocarbon fraction to about 300 μL, measurements were made with gas chromatography (on-column injection) under the following conditions.
(4-1) Column
Precolumn: inactivated fused silica column, 10 m in length, 0.53 mm in inner diameter
Analysis column: 100% dimethylpolysiloxane, 15 m in length, 0.32 mm in inner diameter, 0.1 μm in thickness
(4-2) Injection
Carrier gas: Helium
Injection amount: 40 μL
Inlet temperature condition: 60° C. (retention for 4 minutes).fwdarw.temperature rise at 20° C./minute-380° C. (retention for 15.5 minutes)
Pressure conditions: 60 kPa (retention for 4 minutes) pressure rise at 70 kPa/minute-130 kPa (retention for 30.5 minutes)
Column flow rate: 3.55 mL/minute
(4-3) Oven
Temperature: 50° C. (retention for 4 minutes).fwdarw.temperature rise at 20° C./minute-380° C. (retention for 15 minutes)
(4-4) FID detector
Temperature: 380° C.
(5) Using a chromatogram obtained by gas chromatography measurement in (4) above, the content of the saturated hydrocarbon was specified by making a comparison between an area of the internal standard material and an area of the saturated hydrocarbon (area of a hump building from a base line).

(21) In the following tables, “C20-35” means an amount of a saturated hydrocarbon having 20 or more and 35 or less carbon atoms among saturated hydrocarbons. “C10-56” means an amount of a saturated hydrocarbon having 10 or more and 56 or less carbon atoms among saturated hydrocarbons.

(22) TABLE-US-00001 TABLE 1 Raw material palm- based oils Example Example Example Example Example and/or fats 1 2 3 4 5 Evaporator — 200 220 230 240 250 temperature (° C.) Evaporator vacuum — 0.0500 0.0500 0.0500 0.0500 0.0500 degree (Pa) Feed rate of oils — 0.5 1.5 1.5 1.5 1.5 and/or fats to evaporation surface (kg/h) Feed rate of oils — 8.30 25.0 25.0 25.0 25.0 and/or fats per unit area of evaporation surface (kg/h .Math. m.sup.2) Distillation fraction — 3.4 2.3 .4.0 6.7 9.5 ratio (%) Color 14/1.4 32/3.2 21/2.1 21/2.1 16/1.6 20/2.0 (Y value/R value) Acid value 0.05 0.02 0.02 0.02 0.02 0.02 Peroxide value 0.2 0.2 0.0 0.0 0.0 0.0 CDM (Time) 14.74 2.55 3.93 4.24 4.59 4.01 Slipping inciting 39.0 38.0 38.5 38.3 38.4 37.3 point (° C.) Saturated C20-35 17 <2 <2 <2 <2 <2 hydrocarbon (mg/kg) C10-56 39 10 15 14 12 10 (mg/kg)

(23) As shown in Table 1, it has been found that according to the reduction method of the present invention, it is possible to obtain refined oils and/or fats having low content of a saturated hydrocarbon (refined palm-based oils and/or fats). According to the reduction method of the present invention, an increase in acid value or peroxide value, and autoxidation were suppressed.

(24) As shown in Examples 2 to 5, it has been found that, the higher the temperature (evaporator temperature) of the short path distillation treatment, the more the content of a saturated hydrocarbon can be reduced. From the viewpoint of reducing the content of a saturated hydrocarbon while increasing a yield by reducing a distillation fraction ratio, the temperature of the short path distillation treatment is preferably 230° C. or lower.

(25) As shown from a comparison between Example 1 and Example 5, it has been found that, even when the temperature of the short path distillation treatment is low, it is also possible to obtain refined oils and/or fats having low content of a saturated hydrocarbon by lowering the feed rate of raw material oils and/or fats to an evaporation surface of a short path distillation apparatus, as is the case with high temperature of the short path distillation treatment.

(26) <Test 2: Study on Temperature Conditions in Short Path Distillation Treatment>

(27) In the same manner as in Test 1, raw material palm-based oils and/or fats (which are RBD palm oils and correspond to raw material oils and/or fats) were subjected to a short path distillation treatment under the conditions shown in Table 2. Regarding raw material palm-based oils and/or fats before a short path distillation treatment, and a residual fraction after the short path distillation treatment (which corresponds to refined oils and/or fats), the content of a saturated hydrocarbon was measured in the same manner as in Test 1. The results are shown in Table 2.

(28) TABLE-US-00002 TABLE 2 Raw material palm-based oils and/or Example Example Example Example Example Example Example fats 6 7 8 9 10 11 12 Evaporator — 80 100 120 140 160 180 200 temperature (° C.) Evaporator — 0.0068 0.0068 0.0068 0.0068 0.0068 0.0096 0.0097 vacuum degree (Pa) Feed rate of — 1.5 1.5 1.5 1.5 1.5 1.5 1.5 oils and/or fats to evaporation surface (kg/h) Feed rate of — 25.0 25.0 25.0 25.0 25.0 25.0 25.0 oils and/or fats per unit area of evaporation surface (kg/h .Math. m.sup.2) Saturated 19 10 13 10 10 11 7 4 hydrocarbon C20-35 (mg/kg)

(29) As shown in Table 2, it has been found that the higher the temperature (evaporator temperature) of the short path distillation treatment, the more the content of a saturated hydrocarbon can be reduced.

(30) Even when the temperature of the short path distillation treatment is low, there is a tendency to obtain refined oils and/or fats having low content of a saturated hydrocarbon by lowering the pressure (degree of vacuum of an evaporator) of a short path distillation treatment, as is the case with high temperature of the short path distillation treatment.

(31) <Test 3: Study on Number of Short Path Distillation Treatment>

(32) In the same manner as in Test 1, raw material palm-based oils and/or fats (which are RBD palm oils and correspond to raw material oils and/or fats) were subjected to a short path distillation treatment under the conditions shown in Table 3 and then a residual fraction was collected (“1 Pass” in Table 3). Next, the residual fraction (1 Pass) was subjected again to similar short path distillation treatment and then a residual fraction was collected (“2 Pass” in Table 3). Next, the residual fraction (2 Pass) was subjected again to similar short path distillation treatment and then a residual fraction was collected (“3 Pass” in Table 3). Regarding 10 g of raw material palm-based oils and/or fats before a short path distillation treatment, and 10 g of each residual fraction after the short path distillation treatment (which corresponds to refined oils and/or fats), the content of a saturated hydrocarbon was measured in the same manner as in Test 1. The results are shown in Table 3.

(33) TABLE-US-00003 TABLE 3 Raw material palm- 1 2 3 based oils and/or fats Pass Pass Pass Evaporator temperature (° C.) — 80 80 80 Evaporator vacuum degree (Pa) — 0.0068 0.0072 0.0075 Feed rate of oils and/or fats to — 1.5 1.5 1.5 evaporation surface (kg/h) Feed rate of oils and/or fats — 25.0 25.0 25.0 per unit area of evaporation surface (kg/h .Math. m.sup.2) Saturated hydrocarbon 19 9 8 7 C20-35 (mg/kg)

(34) As shown in Table 3, it has been found that it is possible to more reduce the content of a saturated hydrocarbon by repeating a short path distillation treatment.