JPH04363394A - Production of desulfurized fat and oil of fatty acid ester, production of alcohol using the same fat and oil or fatty acid ester - Google Patents

Abstract

PURPOSE:To obtain desulfurized fats and oils or a fatty acid ester for producing a high-purity high-quality alcohol in high yield by catalytically reducing fats and oils or a fatty acid ester in the presence of a specific copper-based ester reducing catalyst under a specific condition. CONSTITUTION:Fats and oils or a fatty acid ester is brought into contact with an ester reducing catalyst shown by the formula Cu.Xx.Yy.Oz (X is Fe, Zn or Cr; Y is Al, Si or Ti; (x) and (y) are atomic ratios of each element when Cu is regarded as 1, x=0.22-2.4; y=0-2.0; (z) is atomic ratio of 0 satisfying requirement for valencies of X and Y), and catalytically reduced in an atmosphere of hydrogen and/or an inert gas under 0.1-20kg/cm<2> (absolute pressure) at 100-350 deg.C to give the objective desulfurized fats and oils or desufurized fatty acid ester.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing desulfurized fats and oils or fatty acid esters, and a method for producing alcohol using the desulfurized fats and oils or fatty acid esters. Specifically, when producing corresponding hydrogenated fatty acids, fatty alcohols, and fatty amines by various hydrogenation catalytic reactions using oils and fats or fatty acid esters as raw materials,
A desulfurization method for obtaining fats and oils and fatty acid esters in which the concentration of sulfur compounds having a catalyst poisoning effect contained in raw oil is reduced by pre-treatment with a specific catalyst containing copper, and a desulfurization method for obtaining fats and oils and fatty acid esters that have a reduced concentration of sulfur compounds that have a catalyst poisoning effect contained in raw oil, and using oils and fats or fatty acid esters as raw materials, A method for producing alcohol that makes it possible to increase the active life of an ester reduction catalyst by using the desulfurized oil or fat or fatty acid ester when producing alcohol by catalytic reduction with hydrogen in the presence of an ester reduction catalyst. It is related to.

0002

[Prior art and problems to be solved by the invention] Fats and oils (in the present invention, fats and oils refer to triglycerides)
and fatty acid esters derived therefrom (in the present invention, fatty acid esters refer to esters of fatty acids and lower or higher alcohols other than triglycerides) usually contain at least several to several tens of ppm of sulfur. When producing hydrogenated fatty acids, aliphatic alcohols, aliphatic amines, etc. using these feedstock oils, trace amounts of sulfur compounds contained in the feedstock oils degrade the hydrogenation catalysts used in each manufacturing process, reducing the catalytic activity. and significantly reduce catalyst life. In particular, when these feedstocks are catalytically reduced with hydrogen in the presence of an ester reduction catalyst to produce alcohol, trace amounts of sulfur compounds contained in the feedstock act as catalyst poisons and shorten the active life of the ester reduction catalyst. Significantly lower. Therefore, the present inventors investigated the above-mentioned purification method in order to reduce the sulfur concentration contained in oils and fats or fatty acid esters that are raw materials for producing alcohol, etc., and found the following problems. It became.

(1) Problems with distillation refining process When fatty acid methyl esters derived from natural fats and oils are distilled using conventional methods, the yield is 90%, and the sulfur compounds are 10% of the initial concentration.
% and can be reduced to 20% with 98% yield. However, when attempting to reduce the sulfur content to a desired level using commonly available or manufactured fatty acid methyl esters,
A distillation loss of 5% or more is unavoidable, and the problem arises that the raw material alkyl distribution also changes significantly. Furthermore, in the case of distilling esters of fats and oils or fatty acids and higher alcohols, it has been substantially difficult to remove the sulfur compounds contained in them by distillation because these have high boiling points.

(2) Problems with refining treatment using desulfurization catalysts Molybdenum or tungsten catalysts are used in the field of petroleum refining to remove sulfur compounds from light oil or heavy oil (Catalyst Process Chemistry, Tokyo Kagaku Doujin Shuppan) )
. However, in order to obtain desulfurization activity, these catalysts require
Requires high temperature of 300°C or higher. When oils and fats and fatty acid esters are hydrogenated at such high temperatures, problems arise such as an increase in acid value (AV) and a significant increase in raw material decomposition products due to the hydrogenolysis of ester groups. Elution of catalyst components occurs, causing a problem in that selectivity is adversely affected during the ester reduction reaction.

[0005] Therefore, the object of the present invention is to provide a method for producing desulfurized fats and oils and fatty acid esters that reduces the concentration of sulfur compounds that have a catalyst poisoning effect contained in the fats and oils or fatty acid esters, and a method that reduces the life of the ester reduction catalyst. The object of the present invention is to provide a method for efficiently producing high-quality alcohol with high yield, high purity, and high purity by catalytically reducing fats and oils or fatty acid esters in the presence of an ester reduction catalyst.

[0006]

[Means for solving the problem] Therefore, the present inventors
Using fats and oils or fatty acid esters derived therefrom,
As a result of intensive research to establish a refining technology to reduce the sulfur concentration in raw material oil to a desired level in the process of producing alcohol, etc., we have found that oils and fats or fatty acid esters can be purified by hydrogen and hydrogen using a specific catalyst. The present invention has been completed based on the discovery that raw material oil suitable for the purpose can be produced with good yield by processing under an inert gas atmosphere. That is, in the present invention, oil or fat or fatty acid ester is heated under a hydrogen and/or inert gas atmosphere at a pressure of 0.1 to 20 kg/cm.
2 (absolute pressure) and a temperature of 100 to 350° C., the present invention provides a method for producing a desulfurized fat or oil or fatty acid ester, which is characterized by contacting the desulfurized oil or fat or fatty acid ester with a catalyst represented by the following formula (I), Furthermore, in the present invention, when producing alcohol by catalytic reduction with hydrogen in the presence of an ester reduction catalyst using oil or fatty acid ester as a raw material, the oil or fatty acid ester is subjected to the following treatment in advance in a hydrogen and/or inert gas atmosphere. In the presence of the catalyst represented by formula (I), the pressure is from 0.1 to
20kg/cm2 (absolute pressure), temperature 100-350
The present invention provides a method for producing alcohol, which is characterized in that it uses a raw material with a low sulfur content, which is treated at a temperature of 0.0 °C to reduce the sulfur content in the treated oil to 0.6 ppm or less.

Formula (I): Cu・Xx・Yy
・Oz (wherein, X contains at least one element of Fe, Zn, and Cr; Y contains at least one element of Al, Si, and Ti; Indicates the atomic ratio of each element in the case, x = 0.02 ~
2.4, y=0 to 2.0. Here z is
and Y is the atomic ratio of oxygen that satisfies the valence requirements of the element. ) Hereinafter, the present invention will be explained in detail.

When fats and oils and fatty acid esters derived therefrom are catalytically reduced with hydrogen in the presence of an ester reduction catalyst to produce the corresponding aliphatic alcohol, the catalyst life is greatly affected by the quality of the raw oil. Therefore, the present inventors conducted a detailed study on the impurities in these feedstock oils that greatly affect the life of the ester reduction catalyst, and found that in addition to sulfur compounds and halides, which are known as catalyst poisons, free fatty acids It was found that the catalyst exhibited extremely strong toxicity. Sulfur compounds and halides are generally well known as catalyst poisons for hydrogenation reaction catalysts.
During the reaction, it is desirable to reduce these catalyst poisons as much as possible. Here, since commonly available feedstock oils contain only trace amounts of halides, reducing the concentration of sulfur compounds is most important. Furthermore, the ester reduction catalysts used industrially are copper-chromium or copper-zinc catalysts, and are therefore susceptible to corrosion by free fatty acids. Therefore, it is important to reduce the fatty acid concentration in the raw oil as much as possible.

[0009] Therefore, in order to investigate the permissible concentration of sulfur compounds and free fatty acids in raw oil, we conducted an investigation using methyl ester derived from coconut oil or palm kernel oil by a conventional method as a raw material and a copper-based catalyst. . For comparison, the above raw material was distilled (distillation yield 90%), and the sulfur content was 0.
．． 3 to 0.4 ppm, acid value (AV, KOHmg/g
) of 0.1 or less was used. As a result, the sulfur content is 0.6 ppm or less, more preferably 0.3 ppm or less.
It has been found that if the raw material has an acid value (AV) of ppm or less and an acid value (AV) of 2 or less, a catalyst life almost equivalent to that of distilled methyl ester can be secured.

Sulfur compounds contained in fats and oils and fatty acid esters derived therefrom cannot be completely removed even through conventional purification treatments such as adsorbent treatment, alkali treatment, or steaming treatment. Even when sufficient purification treatment is performed using these methods, 3 to 5 ppm
Some sulfur content remains. For this reason, even if we try to reduce the sulfur content any further, it is impossible with normal refining processes.
Therefore, at present, it can be said that there is no other means other than distillation purification. On the other hand, free fatty acids can be easily reduced by ordinary purification treatments such as adsorbent treatment, alkali treatment, or steaming treatment.

[0011] Therefore, the present invention provides an inexpensive and efficient refining method to replace the distillation refining method for reducing the sulfur content contained in fats and oils and fatty acid esters derived therefrom, and The present invention provides a method for producing alcohol using a raw material with a low sulfur content obtained by a treatment method. Regarding the fatty acid ester used in the present invention, it is possible to use a fatty acid ester that has been distilled in advance in the presence of the catalyst represented by formula (I) above, prior to the step of purification under specific conditions. Needless to say.

[0012] The fats and oils used in the present invention include:
Examples include animal and vegetable oils such as coconut oil, palm oil, palm kernel oil, soybean oil, rapeseed oil, beef tallow, lard, or fish oil, or hydrogenated oils thereof. Furthermore, fatty acid esters used in the present invention include lower or higher alcohol esters of fatty acids. The fatty acids constituting this fatty acid ester include caproic acid, caprylic acid, capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, eicosanoic acid, docosanoic acid, oleic acid, erucic acid, etc. As the alcohol constituting the alcohol, linear or branched saturated or unsaturated alcohols having one or more carbon atoms are used, such as methanol,
Ethanol, 1-propanol, 2-propanol, 1
-butanol, 2-butanol, 2-ethylhexanol, 2,2-dimethyl-1,3-propanediol,
Ethylene glycol, propylene glycol, 1,4
-butanediol, 1,6-hexanediol, 1,
Examples include 10-decanediol, cyclohexanol, benzyl alcohol, diethylene glycol, glycerin, trimethylolpropane, and the like.

[Desulfurization Step] The copper-containing desulfurization purification catalyst used in the present invention has a composition represented by the above formula (I). The composition of the desulfurization catalyst represented by formula (I) is very important in terms of desulfurization activity. The method for producing the desulfurization catalyst represented by formula (I) is not particularly limited, and is prepared by firing a mixture obtained by a coprecipitation method, an impregnation method, a homogeneous kneading method, or the like. Note that these preparation methods can also be used in combination as necessary.

[0014] Also, the formula (I) used in the present invention
The catalyst represented by can be used supported on a carrier or mixed with a carrier. The carriers used here are silica, alumina, silica alumina, zeolite, diatomaceous earth,
It is selected from known carriers such as activated clay, titania, zirconia, and activated carbon. The catalyst represented by formula (I) containing a carrier component is appropriately selected from powder catalysts and catalysts shaped into spheres, cylinders, etc., depending on the treatment reaction method, and is used. These catalysts are activated by reduction with hydrogen before use. Further, depending on the case, a catalyst which has been subjected to reduction activation and stabilization treatment in advance by a known method may be used as it is or after being reductively activated.

[0015] Regarding the desulfurization treatment reaction method, any of continuous, semi-batch or batch methods can be adopted;
A continuous method is especially suitable when processing a large amount. In the case of a continuous system, widely used reaction systems such as fixed bed, moving bed, and fluidized bed systems, such as catalytic desulfurization, catalytic cracking, or catalytic reforming in petroleum refining, can be applied. In general, when the sulfur concentration in the feed oil is relatively low, a fixed bed method is particularly preferable because it can utilize a high concentration of catalyst, and when the sulfur concentration in the feed oil is high, a catalyst with decreased performance is continuously Exchangeable moving bed and fluidized bed systems can also be used.

Fats and oils or fatty acid esters derived therefrom are treated in the presence of a catalyst represented by formula (I), for example, in a fixed bed continuous reaction system using the following catalyst. That is, the processing gas is hydrogen and/or an inert gas, and examples of the inert gas include nitrogen, argon, helium, methane, and the like. Processing pressure is 0.1-20kg/cm
2 (absolute pressure, the same applies hereinafter). In this case, in terms of desulfurization activity and suppression of decomposition of feedstock oil, 1 to 5 kg/c
m2 is more preferred. In a hydrogen gas atmosphere, as the pressure increases, the amount of hydrocracking byproducts from the feedstock oil increases due to desulfurization. In addition, the treatment temperature is determined within the range of 100 to 350 °C, but if the temperature is low, the desulfurization activity is decreased, and if the temperature is high, thermal decomposition by-products of the feedstock oil, and in a hydrogen atmosphere, hydrogen is Since the amount of chemical decomposition by-products increases, it is desirable to carry out the treatment at a temperature in the range of 150 to 300°C.

The feed rate of the oil or fat or fatty acid ester, which is the raw material oil for processing, is 0.1 to 5.0 in terms of reaction column volume ratio per hour, that is, liquid hourly space velocity (hereinafter referred to as LHSV).
Although it is preferable to set it to 0 Hr-1, if it becomes small, it will be disadvantageous in terms of productivity. In the fixed bed continuous reaction system,
The raw material oil to be treated may be circulated together with the circulating gas in an upward cocurrent flow (upflow system), a downward cocurrent flow (trickle flow system), or a countercurrent flow (counterflow system). However, when the liquid flow rate or gas flow rate is large, the countercurrent method is disadvantageous, and
The upward parallel flow method also has disadvantages in terms of the need for catalyst strength and the pressure loss of the flowing gas. In this case, a downward parallel flow system is preferably adopted.

When the sulfur compounds in fats and oils and fatty acid esters derived therefrom are purified and removed under the above conditions, in order to maintain the sulfur content at 0.6 ppm or less, the refining treatment conditions must be adjusted. In selecting the acid value (AV
) can be naturally considered to be operated under conditions where it is expected to be high. Therefore, when performing the refining treatment under conditions where it is necessary to suppress an increase in acid value (AV), a monohydric or polyhydric alcohol having 1 to 18 carbon atoms may be mixed in advance into the raw oil. According to this method, the acid value (A
V). The amount of alcohol added to the raw material oil can be 10 to 1000 times, more preferably 20 to 500 times by mole, the amount of free fatty acid produced or expected under the reaction conditions. The monohydric or polyhydric alcohol having 1 to 18 carbon atoms used here includes, for example, methanol, ethanol, propanol, isopropanol, butanol, secondary butanol,
Tertiary butanol, pentanol, hexanol, heptanol, octanol, decanol, dodecanol, tetradecanol, hexadecanol, octadecanol or ethylene glycol, propylene glycol,
Refers to butanediol, glycerol, etc.

The desulfurized fat or oil or fatty acid ester thus obtained can be used not only as a raw material for producing alcohol, but also as a raw material for producing hydrogenated fatty acids or aliphatic amines.

[Alcohol production step by catalytic reduction] The oil or fat or fatty acid ester with a sulfur content of 0.6 ppm or less obtained according to the purification process disclosed in the present invention is then catalytically reduced with hydrogen using an ester reduction catalyst. This leads to the corresponding alcohol. As the ester reduction catalyst used here, a copper-based ester reduction catalyst is preferable, and the main component is copper, such as known catalysts such as copper-chromium, copper-zinc, copper-iron-aluminum, and copper-silica. Examples include catalysts such as The ester reduction reaction is
In the presence of the above-mentioned catalyst, the reaction may be carried out using either a liquid phase suspension bed or a fixed bed reaction method. Regarding the catalytic reduction conditions,
Conventionally known methods may be used, but when a liquid phase suspended bed reaction method is adopted, the amount of catalyst is 0.00% relative to the fat or oil or fatty acid ester.
The amount is preferably 1 to 20% by weight, but it can be arbitrarily selected depending on the reaction temperature or reaction pressure within a range that provides a practical reaction rate. Reaction temperature is 160-350℃
, preferably 200 to 280°C. The reaction pressure is 1 to 350 kg/cm2, preferably 30 to 300 kg/cm2.
kg/cm2. Further, when a fixed bed reaction method is adopted, a catalyst shaped into a cylinder, pellet, or sphere is used. Reaction temperature is 130-300℃
, preferably 160 to 270°C. The reaction pressure is 0.1 to 300 kg/cm2. Here, LHSV is arbitrarily determined depending on the reaction conditions, but in consideration of productivity or reactivity, it is preferably in the range of 0.5 to 5 Hr-1.

[0021]

EXAMPLES The present invention will be explained in more detail with reference to Examples below, but the present invention is not limited to these Examples.

Desulfurization Catalyst Preparation Example I (Desulfurization Catalyst A) Stirrer,
Pure water in a 2 liter 4-necked flask with a thermometer 27
Add 3g of Cu(NO3)2.3H and heat to 90℃.
2O 66.4g and Zn(NO3)2.6H2O
Metal salt aqueous solution in which 53.3g was dissolved in 190g of pure water,
and 17% by weight aqueous sodium carbonate solution, pH=5
．． It was added dropwise at the same time while maintaining the temperature at 7 to 6.3. after that,
Add 10% by weight aqueous sodium hydroxide solution, pH = 9
．． 5, and the resulting precipitate was filtered, washed with water, dried, and then calcined at 450°C for 2 hours to form Cu:Zn.
An oxide having a composition of =1:0.65 (atomic ratio) was obtained.

Desulfurization Catalyst Preparation Example II (Desulfurization Catalyst B) Pure water and titanium oxide were placed in a 2 liter 4-necked flask equipped with a stirrer and a thermometer, heated to 98°C, and Cu(
A mixed aqueous solution of NO3)2.3H2O and Zn(NO3)2.6H2O and a 10% by weight aqueous sodium carbonate solution were simultaneously dropped while maintaining the pH in the range of 5 to 6, and then the pH of the solution was adjusted to 9. A 10% by weight aqueous sodium carbonate solution was added until the mixture was dissolved. After filtering, washing with water, and drying the generated precipitate, Cu was calcined at 450°C for 2 hours.
An oxide having a composition of :Zn:Ti=1:0.05:0.8 (atomic ratio) was obtained.

Desulfurization Catalyst Preparation Example III (Desulfurization Catalyst C) In a 2 liter 4-necked flask equipped with a stirrer and a thermometer, 762 g of pure water, 44.6 g of sodium aluminate, and CuS were added.
O4 ・5H2O 113.2g, FeSO4 ・7H
Add 151.2g of 2O, heat to 98℃, and add 2O.
528.3g of 2% by weight aqueous sodium carbonate solution 1
It was added dropwise in 20 minutes. Subsequently, a 10% by weight aqueous sodium hydroxide solution was added until the pH = 10.5, and the resulting precipitate was filtered, washed with water, dried, and then calcined at 600°C for 1 hour to form Cu:Fe:Al. =1:1.1
:1.2 (atomic ratio) was obtained.

Desulfurization Catalyst Preparation Example IV (Desulfurization Catalyst D, Desulfurization Catalyst E) The resulting oxides have (D)C
u:Fe:Al=1:1.2:0(E)Cu:Fe:
A catalyst having a composition expressed by Al=1:1.2:2.0 was obtained in the same manner as in Desulfurization Catalyst Preparation Example III.

Example 1 (Desulfurization step) Using desulfurization catalyst A, palm kernel fatty acid methyl ester was desulfurized. The desulfurization catalyst was extrusion molded using bentonite to form a noodle-shaped molded body with a length of 5 mm and a diameter of 2 mm. This molded body 270cc has an inner diameter of 28mm.
The reduction activity of the desulfurization catalyst was increased by filling a reaction tube with nitrogen gas containing 5 to 60% by volume of hydrogen at 185°C and flowing it under normal pressure at a gas flow rate of about 140 liters/hour for 7.5 hours. . After this, 3.6
While circulating palm kernel fatty acid methyl ester having a sulfur concentration of ppm and hydrogen-containing gas in parallel downward flow,
Desulfurization of feedstock oil was carried out under various conditions in a 100% hydrogen atmosphere. The results of sulfur concentration analysis of the obtained palm kernel fatty acid methyl ester are shown in Table 1 below. The sulfur concentration was determined by Rosemount Analytical In
c. Dohrmann type low concentration sulfur analyzer (S
system 701). In addition, the recovery rate of the obtained palm kernel fatty acid methyl ester was substantially 10
0%, and there was no loss of palm kernel fatty acid methyl ester during the desulfurization process.

[0027]

[Table 1]

Example 2 (Desulfurization step) Using desulfurization catalyst C, palm kernel fatty acid methyl ester containing 3.6 ppm of sulfur was desulfurized in the same manner as in Example 1. The results obtained by processing under various conditions in a 100% hydrogen atmosphere are shown in Tables 2 and 3 below.
Shown below. The recovery rate of the obtained palm kernel fatty acid methyl ester was substantially 100%, and there was no loss of palm kernel fatty acid methyl ester in the desulfurization process.

[0029]

[Table 2]

[0030]

[Table 3]

Example 3 (Desulfurization step) Using desulfurization catalyst B, palm kernel fatty acid methyl ester containing 3.6 ppm of sulfur was desulfurized in the same manner as in Example 1. Table 4 shows the results obtained under the processing conditions described below. Processing pressure = 1kg/cm2, processing temperature = 200℃,
Distribution gas and flow rate = 100% hydrogen gas 2300
Nl/Hr, LHSV=2Hr-1 The recovery rate of the obtained palm kernel fatty acid methyl ester was substantially 100%, and there was no loss of palm kernel fatty acid methyl ester in the desulfurization process.

Example 4 (Desulfurization step) Desulfurization treatment was carried out by the method described in Example 3 except that desulfurization catalyst D was used. The results are shown in Table 4. The recovery rate of the obtained palm kernel fatty acid methyl ester was substantially 100%, and there was no loss of palm kernel fatty acid methyl ester in the desulfurization process.

Example 5 (Desulfurization step) Desulfurization treatment was carried out by the method described in Example 3 except that desulfurization catalyst E was used. The results are shown in Table 4. The recovery rate of the obtained palm kernel fatty acid methyl ester was substantially 100%, and there was no loss of palm kernel fatty acid methyl ester in the desulfurization process.

Example 6 (Desulfurization step) Desulfurization treatment was carried out by the method described in Example 3 except that a commercially available copper-chromium catalyst (Cu:Cr=1:1) was used. The results are shown in Table 4. In addition, the recovery rate of the obtained palm kernel fatty acid methyl ester was practically 100%,
There was no loss of palm kernel fatty acid methyl ester during the desulfurization process.

[0035]

[Table 4]

Example 7 (Desulfurization Step) Desulfurization of refined palm kernel oil containing 4.0 ppm of sulfur was carried out in the same manner as in Example 1 using Desulfurization Catalyst C. The results obtained by processing under various conditions in a 100% hydrogen atmosphere are shown in Table 5 below. The recovery rate of the palm kernel oil obtained was essentially 100%, and there was no loss of palm kernel oil during the desulfurization process.

[0037]

[Table 5]

Example 8 (Desulfurization step) Using desulfurization catalyst C, palm kernel fatty acid methyl ester containing 3.6 ppm of sulfur was desulfurized in the same manner as in Example 1. Table 6 below shows the results of examining the effect of treatment temperature under conditions of 1 kg/cm2 treatment pressure, 2 Hr-1 LHSV, and 2300 Nl/Hr flowing nitrogen in a 100% nitrogen atmosphere. The recovery rate of the obtained palm kernel fatty acid methyl ester was substantially 100%, and there was no loss of palm kernel fatty acid methyl ester in the desulfurization process.

[0039]

[Table 6]

Comparative Example 1 (Desulfurization Step) In order to remove sulfur compounds from palm kernel fatty acid methyl ester, ordinary distillation purification was attempted as a comparative example. The palm kernel fatty acid methyl esters used here were from Examples 1 to 3.
It is the same as 6. After charging 6 kg of raw material methyl ester into a 10 liter distiller, the degree of vacuum is 1 to 2 mm.
Distillation is carried out under Hg conditions. After about 3 kg of raw material was distilled off, the raw material methyl ester was added again and distillation was continued to purify a total of 8.02 kg of methyl ester. At this time, the sulfur content relative to the distillation rate was investigated by measuring the sulfur content contained in the distilled methyl ester. The results obtained are shown in Table 7 below.

[0041]

[Table 7]

[0042] When the raw material distillation rate is 95%, the alkyl composition of the raw material ester remaining as the distillation bottom is C10.
The methyl ester content was 80% or more. Therefore, in the distillation purification method, it is difficult to avoid the disadvantage of increased loss of C16 to C18 long chain methyl esters.

Example 9 In order to investigate the influence of the sulfur concentration in the reduced feedstock oil on the active life of the ester reduction catalyst, the oil obtained by the treatment under the low pressure conditions shown in Examples 1 to 6 and Comparative Example 1 was used. An investigation was conducted using it as a reducing raw material. Table 8 shows the reduced raw material oil used here, and Table 9 shows the results of evaluating the active life of the ester reduction catalyst using this raw material oil by the method shown below. The ester reduction catalyst used here is disclosed in JP-A-1-
It is a titania-supported copper-zinc catalyst disclosed in Publication No. 305042, CuO:ZnO:TiO2=47.5%
:2.5%:50.0%.

<Method for evaluating activity life of ester reduction catalyst>
150 g of reduced raw material oil and 3.75 g of ester reduction catalyst were placed in a rotary stirring 0.5 liter autoclave.
The catalyst was activated by reduction for 2 hours under hydrogen flow at a hydrogen pressure of 10 kg/cm2 and a temperature of 200°C. After that, the temperature was raised to 230 °C and the hydrogen pressure was increased to 120 kg/cm2.
The reaction was started at a stirring speed of 800 rpm and a hydrogen flow rate of 5 liters/min. Sampling was performed appropriately during the reaction, and the activity was determined by determining the conversion rate of ester. The reaction was organized as a first-order reaction with respect to the ester concentration, and the rate constant per gram of ester reduction catalyst before activation was used as a measure of activity. After the reaction is complete, the catalyst and alcohol produced are separated by filtration, the recovered catalyst is used in the reaction again, and this operation is repeated 10 times in total under the same conditions to determine the rate constant for each reaction. The activity reduction rate per unit was calculated. In a series of experiments, the change in rate constant with respect to the number of catalyst collections showed good linearity.

[0045]

[Math 1]

K1 = 1st rate constant K10 = 10th rate constant

[0047]

[Table 8]

[0048]

[Table 9]

From the above results, it was found that raw oils (raw oils A, C, D, E, F, G) whose sulfur concentration was reduced to 0.6 ppm or less by the desulfurization treatment of the raw oil disclosed in the present invention were used. In this case, a value smaller than the activity reduction rate of distilled methyl ester (raw oil H) was obtained, and the distillation refining treatment (distillation yield = 90.1
%), it is clear that an active life equivalent to or higher than that of

[0050]

According to the present invention, fats and oils or fatty acid esters with reduced sulfur content can be obtained extremely efficiently. Moreover, by using the method for producing alcohol of the present invention, when producing alcohol from fats and oils or fatty acid esters, it is possible to increase the active life of the ester reduction catalyst. Furthermore, according to the present invention, by efficiently lowering the sulfur concentration contained in the oil or fat or fatty acid ester, the resulting oil or fatty acid ester is subjected to a hydrogenation reaction in the presence of an ester reduction catalyst, resulting in a high yield. , high purity and high quality alcohol can be obtained efficiently.

Claims (7)

[Claims] Claim 1: Oil or fat or fatty acid ester is heated under a hydrogen and/or inert gas atmosphere at a pressure of 0.1 to 20 kg/
cm2 (absolute pressure), at a temperature of 100 to 350 °C,
A method for producing a desulfurized fat or oil or fatty acid ester, which comprises bringing it into contact with a catalyst represented by the following formula (I). Formula (I): Cu・Xx・Yy・Oz (
In the formula, X 2 contains at least one element of Fe, Zn, and Cr, and Y 2 contains at least one element of Al, Si, and Ti. In addition, x and y indicate the atomic ratio of each element when Cu is 1, x = 0.02 to 2.4,
y=0 to 2.0. Here z is X and Y
It is the atomic ratio of oxygen that satisfies the valence requirements of the element. ) 2. The desulfurized fat or fatty acid according to claim 1, wherein the contact between the fat or oil or fatty acid ester and the catalyst is to continuously pass the fat or fatty acid ester through a fixed bed packed with a catalyst. Method for producing esters. [Claim 3] Using oil or fat or fatty acid ester as a raw material,
When producing alcohol by catalytic reduction with hydrogen in the presence of an ester reduction catalyst, fats and oils or fatty acid esters are preliminarily reduced under pressure in the presence of a catalyst represented by the following formula (I) in a hydrogen and/or inert gas atmosphere. 0.1~20kg/cm2
(absolute pressure) and a temperature of 100 to 350° C. A method for producing alcohol characterized by using a raw material having a low sulfur concentration, which is treated at a temperature of 100 to 350° C. so that the sulfur concentration in the treated oil is 0.6 ppm or less. Formula (I): Cu・Xx・Yy・Oz (
In the formula, X 2 contains at least one element of Fe, Zn, and Cr, and Y 2 contains at least one element of Al, Si, and Ti. In addition, x and y indicate the atomic ratio of each element when Cu is 1, x = 0.02 to 2.4,
y=0 to 2.0. Here z is X and Y
It is the atomic ratio of oxygen that satisfies the valence requirements of the element. ) [Claim 4] Oil or fat or fatty acid ester is treated with hydrogen and/or
4. The method for producing alcohol according to claim 3, wherein a continuous reaction method is used in the treatment with the catalyst represented by the formula (I) in an inert gas atmosphere. 5. The method for producing alcohol according to claim 4, wherein the continuous reaction system is a fixed bed continuous reaction system. [Claim 6] Acid value in treated oil (KOHmg/g)
The method for producing alcohol according to any one of claims 3 to 5, wherein the alcohol is 2 or less. [Claim 7] The sulfur content concentration in the treated oil is 0.3 ppm.
The method for producing alcohol according to any one of claims 3 to 6, characterized in that: