KR800001185B1 - Hydrogenation of glyceride oil - Google Patents

Abstract

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Description

Hydrogenation of glyceride oil

Figure 1: A scaled graph showing iodine value against hydrogenation time in a series of hydrogenation steps that are compared.

FIG. 2: A scaled graph showing the rate of hydrogenation in the three steps of FIG. 1 versus nickel catalyst concentration.

FIG. 3: A scaled graph plotting iodine value against hydrogenation time to show the effect of soap drop on the hydrogenation process using only nickel catalyst as compared to the use of the present invention.

4 is a scaled graph showing iodine value with respect to hydrogenation time in a series of six hydrogenation steps according to the two-stage method of the present invention.

FIG. 5: Gradual graph showing the intermediate iodine number, which determines the primary hydrogenation of the five stages of FIG. 4, for the total hydrogenation time of the stearin product having iodine 3.

FIG. 6: A scaled graph showing the hydrogenation time of the hydrogenation stages compared with each other and the iodine value obtained in stage 2 of FIG.

FIG. 7: A scaled graph showing the hydrogenation time for the hydrogenation stages compared to the hydrogenation time and the iodine value obtained in stage 6 of FIG. 4.

The present invention relates to a method of catalytically hydrogenating triglyceride oils and, in particular, to rapidly hydrogenating oils containing contaminated soap.

To date, oil has been catalytically hydrogenated in the presence of nickel catalysts, copper-chromium steel (optionally stabilized metal oxides), or a combination of these two catalysts. Typically, a combination of the two catalysts is used to contact the oil to prevent acid decay or to produce a product with a shorter iodine value (a suitable iodine value of about 60-65). Feed oils have been refined to remove contaminated soaps and free fatty acids that are susceptible to catalyst contamination and ineffective in hydrogenation processes.

The present invention makes it possible to catalytically hydrogenate oil in the presence of a relatively large proportion of contaminated soap and free fatty acids. The hydrogenation process proceeds very quickly when the iodine produces a hydrogenated oil product having 60-100 and is surprisingly fast when producing a product stearin having an iodide of about 30 or less. Glyceride oil is catalytically hydrogenated with hydrogen gas in the hydrogenation zone of hydrogen under glyceride oil hydrogenation conditions to produce a hydrogenated oil product. The hydrogenation process proceeds practically insensitive to the presence of the contaminants in the presence of nickel hydrogenation catalysts and copper-chromium steel cocatalysts. The nickel catalyst is present in an excess of 0.02% by weight of oil and the cocatalyst is present in at least about 0.25% by weight of oil. The concentration of contaminated soap is at least minimally depressive to the hydrogenation process and is not excess than about 0.25% by weight of oil. The hydrogenation process is stopped at least after a significant increase in saturation of the oil occurs. In a preferred embodiment of the invention, the oil is hydrogenated at an intermediate iodine value of at least 10% less than the iodine value of the oil fed to the hydrogen catalyst process in the presence of the catalyst-cocatalyst. According to this, the oil is rapidly subjected to a second hydrogenation step, only in the presence of a nickel catalyst, to produce the hydrogenated stearin product.

Contaminated soaps in glyceride oils have a depressing effect on the hydrogenation process by contaminating the hydrogenation catalyst and making itself ineffective in the process. Very low levels of soap in oils can be used for most conventional hydrogenation catalysts. ; Although the soap has a minimum soap concentration that begins to develop its depressant effect in the hydrogenation process, the minimum soap concentration appeared at about 0.01% by weight of the oil when proceeding with the one-step process with a nickel catalyst / cocatalyst combination. Soap concentrations below this level can usually be adequately overcome using higher levels of conventional hydrogenation catalysts. Above this level, an increase in the catalyst concentration does not effectively suppress the reinforcing effect of soap in the hydrogenation process. Copper-chromium steel cocatalysts are widely applied in proportion to soap concentrations, effectively suppressing the dropping effect on the process, as clearly seen in one. In the present invention wherein a secondary step using only nickel was used following the catalyst combination step, the minimum amount of soap was about 0.003% by weight of oil. The maximum soap concentration that can be effectively handled by the present invention was determined at about 0.25% by weight of oil. The examples will more fully explain.

The initial iodine value of the feed oil can vary from 10-25 to 150-210 due to the particular choice of oil and due to the large number of oils that have iodine in the range. The primary hydrogenation in the presence of a catalyst / cocatalyst system proceeds very fast at practically constant rates and in the presence of contaminated soap. As used herein, primary hydrogenation refers to the use of catalysts / cocatalysts to catalytically hydrogenate glyceride oil, whether such a system is used in a preliminary process or as a first step to produce stearin. Same as above whether or not a secondary step is used and then nickel only.

The primary hydrogenation continues until at least the saturation of the oil increases significantly. To the fullest extent of the present invention, in using the catalyst / cocatalyst system in a one-stage hydrogenation process, a significant increase in oil saturation means that the last iodine value of the oil is about 100 or less; Oils with shortened iodine values are about 60-70; If a stearin product is desired, it is said to be 30 or less. In the present invention, in the second step using only nickel, "30 or less is desired if the product in saturation of oil is desired. In the present invention, a "significant increase in oil saturation" (from primary hydrogenation) in the second stage using only nickel means at least about 10% of the iodine value of the oil fed to the process is reduced. . The final iodine number of the hydrogenated product recovered from the second zone is about 30 or less to make stearin. When the present invention is run in a one step process using a catalyst / cocatalyst combination, the feed oil may contain about 0.01- about 0.25 weight percent or more of contaminated soap. Hydrogenation practiced typically requires about 0.001- about 0.003% or less of the soap content in the oil. Although the cost of refining increases when more pure oils are required, it is generally possible to produce oils of this quality in commercial refining. In the present invention, it is also possible to use crude feed oil for hydrogenation and thus reduce the refining cost.

Generally, the cocatalyst is at least about 0.25% by weight in the zone based on the weight of the oil in the zone to maintain the speed and efficiency of the process. The cocatalyst may be present up to about 3% by weight or more, depending on the concentration of contaminated soap in the feed oil.

Nickel catalyst is present in the zone at least 0.02% by weight and the transition can vary from 0.025-0.3% by weight or more. When the nickel catalyst is at this high level, the process is very fast regardless of the type of hydrogenated product. Proceed. As a result, the hydrogenation process can very quickly produce stearin products (the iodine is not actually above about 30). In general, only about one hour of hydrogenation time is needed to obtain 30 iodide and an addition time between 1-4 hours is necessary to obtain a hydrogenated product having an iodide of 0-5.

The process also allows for the production of small hydrogenated products having iodine that is practically no greater than about 100, typically 60-100 iodine, and 60-70 iodine when shortened. In fact, it took a short time to hydrogenate, regardless of the concentration of contaminated soap in the feed. Fatty acids in the feed oil tend to inhibit hydrogenation because they resist the hydrogenation of free fatty acids. The process actually proceeds insensitive to the presence of free fatty acids.

When carrying out the present invention in a two-step process using a catalyst / cocatalyst combination as the first step to hydrogenate the oil to the intermediate iodine, the intermediate iodine value is determined by several factors, with two more influential factors being supplied. Contaminated soap concentration in the oil and the first iodine of the feed oil. With regard to the latter, the intermediate iodine value should be at least about 10% lower than the initial iodine value of the oil fed into the primary hydrogenation zone. For feed oils of 50-100 of iodine and especially 100-200 of feed oil during the first hydrogenation period, the range of intermediate iodine prices allowing substantial and rapid hydrogenation according to the process is wider. In this case the intermediate iodine value can vary from 10-20 to about 80-100 and 130-160 with the selected feed oil.

Although the intermediate iodine value of the oil following termination of the primary hydrogenation is within a wide range, there is an intermediate iodine value (or a narrow range of intermediate iodine values) that is optimal for this process. In a special case, soybean oil (first iodine is about 134) was hydrogenated in the primary hydrogenation band to obtain about 45-about 113 intermediate iodine. All these steps were accompanied by full hydrogenation time for both zones to produce stearin product (iodine 0-3) recovered from the secondary zone of about 0.467 hours-about 0.92 hours (about 28 minutes-about 55 minutes). It is within the scope of the present invention. When the intermediate iodine value was about 96, the total hydrogen addition time was minimum and the hydrogenation rate (change in iodine value per unit time) in the secondary zone was maximum. It will be better understood in the examples.

Contaminated soap concentrations in the feed oil are also a factor in part affecting the intermediate iodine value of the oil in the primary hydrogenation range, ie the termination of the primary hydrogenation. Broadly, the intermediate iodine value is inversely proportional to the contaminated soap concentration in the oil, with the high intermediate iodine value allowed at relatively low soap concentrations and the low intermediate iodine value generally favored at relatively high soap concentrations. The feed oil for this process may contain about 0.003 to about 0.25 weight percent contaminated soap and the hydrogenation process proceeds substantially insensitive to the presence of soap in the feed oil. It will be better understood in the examples.

Several other factors affecting this process are as follows.

Contaminants in the feed oil, ie, phosphatid, iron, free fatty acids, etc .; Hydrogenation conditions of temperature and hydrogen gas pressure; Concentration of catalyst in every hydrogenation zone; The efficiency and limitation of catalytic contact with hydrogen gas and oil, typically controlled by mixing and the like; Operation of the process, ie batch or continuous operation; And other factors for which the technique is known. Although proper design of the hydrogenation process can be reduced to a small number for the efficiency of the previous process and ease of control, it is sometimes difficult to apply and match these factors. The exact details of the operation of the process are well-determined and linked together for efficient and economical hydrogenation according to the process.

The present process yields several unexpected surprises, some of which are not fully understood. One such advantage is that the process can efficiently handle feed oils with varying contaminated soap concentrations and is not practically sensitive to such soaps. Another advantage is that the secondary hydrogenation, which only adds nickel hydrogen, is actually improved unexpectedly. Another benefit is the substantial improvement in both hydrogenation (both hydrogenation rate and time) and the short hydrogenation time for the two bands at relatively higher intermediate iodine equivalents of the shorter primary hydrogenation. Optimum conditions, such as process, were obtained on a wide range of intermediate iodine phases. Many other advantages are gained by the present process as described herein.

Speaking of primary hydrogenation, the cocatalyst is generally present in the zone by at least about 0.25% by weight, based on the weight of the oil, to maintain the speed and efficiency of the process. The cocatalyst may be present in about 3% by weight or more, depending on the concentration of contaminated soap in the feed oil. The nickel catalyst is present in the primary hydrogenation zone of at least 0.02% by weight and the transition can vary from about 0.025 to about 0.3% by weight or more. At this high level of nickel catalyst, the process proceeds very quickly to the level of selected intermediate iodine of the oil.

During secondary hydrogenation, the concentration of nickel catalyst is in the range of about 0.01 to about 0.30% by weight, advantageously about 0.05 to about 0.20% by weight and preferably about 0.05 to about 0.15% by weight. Certainly, the cocatalyst in the primary hydrogenation step sufficiently suppresses the effect of the contaminated soap. However, in secondary hydrogenation it is eliminated or at least unnecessary and expensive.

The nickel hydrogenation catalyst may be in a supported or unsupported form for primary and / or primary hydrogenation. Representative support materials include alumina, silica gel, activated carbon, and the like. The nickel catalyst may be obtained by pyrolyzing nickel salts in nickel formate or heat-resistant fat oil at about 425 to 450 ° F. or precipitating the nickel salts on an inert carrier and then reducing them with hydrogen gas. The nickel catalyst can be prepared by electrolytically precipitating nickel hydroxide, which is prepared by direct current through a cell using nickel as a positive electrode and a dilute solution of an alkaline salt of weak acid as an electrolyte. The nickel hydroxide thus produced is usually reduced as in the presence of hydrogen gas. Since the present invention uses known nickel hydrogenation catalysts used today, no particular method for producing nickel hydrogenation catalysts is determined. This purpose with nickel catalysts refers to the nickel metal content of such catalysts.

Copper-chromium steel cocatalysts may be provided in a supported or unsupported form. Copper-chromium steel cocatalysts can be stabilized with alkali metal oxides, such as barium oxide or calcium oxide, or this is not necessary but can be stabilized with polyvalent metal oxides, manganese oxides. Typically, the oxide as stabilizing material varies from about 4-8% by weight of the cocatalyst. The molar ratio to copper chromium components in the cocatalyst is not critical but such components are representative amounts as previously used in hydrogenation techniques. Typically, the molar ratio of such components is about 1: 1. The nickel catalyst and the cocatalyst may be stored simultaneously in an inert carrier or provided in a supported form in the mixture, respectively, but in the present invention, only the catalyst and the cocatalyst are present in the primary hydrogenation zone during the first hydrogenation. need.

The catalyst-cocatalyst is a cooperative combination in the hydrogenation step, but some predominant effect is due to each of the processes.

Copper-chromium iron-assisted catalysts appear to act as soap contamination inhibitors, so that concentrations in the hydrogenation zone can be widely applied in proportion to the concentration of soap contaminants in the feed oil (degrees of phosphatides and free fatty acids). However, the concentration of the cocatalyst should be present at least about 0.25% by weight based on the weight of the oil in the first hydrogenation zone to maintain the speed and efficiency of the entire hydrogenation process. Generally up to about 3% by weight cocatalyst may be used in the process. Higher rates are possible, but a lot of money has to be calculated. Nickel catalysts act as the best (but not the only) catalysts to assist hydrogen absorption by oil. For the overall speed and efficiency of the process, the nickel catalyst should be present at a weight ratio of greater than 0.02 weight percent and this ratio may vary from about 0.025 to about 0.3 weight percent or even higher weight percent during the first hydrogenation.

Typical oil sources are vegetable oils (including nut oils), animal fats and fish oils. Vegetable oils include oils obtained from plants such as coconut, corn, cottonseed, linseed, olives, palms, palm seeds, peanuts, safflower, soybeans, sunflowers, and the like. The oil is refined to remove various impurities such as fatty acids, phosphatides, and non-glycosyls (typically mucus). For the purposes of the present invention the complete ester of glycerol and fatty acids and the fatty acids are slightly unsaturated. The oil is preferably edible.

Alkaline refined oil is the best source for the purposes of the present invention. Alkali purification of the oil uses known methods.

Alkaline refined oil is one of the best sources in the process of the present invention, but it is also useful for steam purification, deacidification by high vacuum distillation or refinement by other means. The basic alkali refining method is to remove the above-mentioned impurities by treating the oil with strong (typically 10-20 ° C) caustic soda. The excess caustic solution (to neutralize all free fatty acids present) is usually mixed with the oil at about 70-90 ° F. This results in the formation of utah, which is decomposed by heating at about 135-145 ° F and the resulting alkaline refined oil is recovered by conventional means such as filtration, decantation, centrifugation, and the like. By-products formed from the decomposition of emulsions are representative of alkali metal soaps of free fatty acids, gums, mucus and phosphatides. Usually this is sent to a separate recovery process, such as to break down fatty acids from soap. For this purpose, the process of the present invention works efficiently and economically for all alkaline refined oils, regardless of the particular alkali purification process used.

The hydrogenation of the present invention reduces the number of ethylene bonds in fatty acid chains to produce materials with lower iodine values and can be used to actually saturate these bonds. As is practiced commercially, the hydrogenation of oil is a liquid phase process, in which gaseous hydrogen is dispersed in heated oil under the influence of a solid catalyst. Although continuous hydrogenation has been carried out, most of the commercial hydrogenation operations used today are batch processes using specific hydrogenation catalysts, where the catalyst is separated from the hydrogenated oil, which is generally a product.

The hydrogenation operation of the present invention consists in charging alkaline refined oil to a hydrogenation reactor having a hydrogenation zone. Hydrogenation conditions for contacting hydrogen gas with oil typically include a temperature of about 100 ° to about 300 ° C. and a pressure of about 0 to about 100 psig. A typical multiaddition reactor is a hydrogen recycle type comprising a cylindrical vessel with a hydrogen distributor at the bottom and excess hydrogen gas is introduced into the oil in the hydrogenation zone through the hydrogen distributor. Another representative of the hydrogenation reaction is a four-stage system using a cylindrical pressurized vessel equipped with a gas dispersed mechanical stirrer which is practically used and leaked from a high pressure hydrogen gas storage tank. Various different hydrogenation reactors are available as products and can be useful for hydrogenating oil.

In the process of the invention all reactions are complete when the iodide of the product represents the iodide of the particular product to be prepared. The iodine value of the primary and the bivalent band contents can be measured constantly by inspecting an index that correlates with the iodine value of the contents, for example, by using a refractive index measurement, an ultraviolet or infrared absorption method, or the like.

The hydrogenation process of the invention can be carried out very advantageously continuously. Generally the catalyst is separated from each other and the hydrogenated intermediate is separated in several ways from both catalysts. A typical route is to support one catalyst as a bed fixed in the hydrogenation zone and leave the other catalyst freely dispersed in oil, or one catalyst to be supported and the other catalyst to an unsupported form for easy separation. By a number of methods the nickel catalyst from the primary hydrogenation step can be separated off and reused as secondary hydrogenation catalyst.

The following examples illustrate in detail how the invention is practiced, but do not limit the scope of the invention. Unless otherwise indicated herein, all percentages and ratios are by weight, all temperatures are in degrees Celsius and mesh sizes are in accordance with the American Standard Series. In addition, all catalyst weight percentages herein are based on the weight in the hydrogenated oil zone unless otherwise indicated. Examples 1-5 illustrate the practice of the present invention as a one-step process using known catalyst / cocatalyst systems, and Examples 6-7 illustrate the subject of performing the second step following the first step to produce stearin. Preferred embodiments of the invention are shown.

Example 1

The feed oil used is from commercial alkali refined soybean oil. The analysis of soybean oil is as follows.

In this and all other examples, the hydrogenation reaction was carried out in a 2 L pressurized vessel equipped with stirrers and electric heaters of various speeds. The air from the reaction vessel was completely removed and the feed oil was charged to the vessel and then heated to 100 ° C. prior to reaction. All iodides were measured by refraction and chemical warfare (wijs method). Soybean oil in the reactor was hydrogenated according to the process of the present invention. This oil was heavily contaminated with soap and other impurities as follows:

Soap 0.21% by weight phosphatides 2803ppm

Iron 0.57 ppm Tint (Lobby Bond) 3.5R-35Y

The hydrogenation conditions are as follows:

Feeding oil 1300g, soybean oil stirring 700r.p.m

Inside with temperature 220 ℃ catalyst 7.2% barium oxide

Purified 3% Copper Chrome Steel Pressure 60psi

0.075% nickel

After about seven hours of hydrogenation, the oil's iodine value was about 60. This result indicates that extremely soap contaminated oil can be rapidly hydrogenated according to the present invention. From then on, the hydrogenation process is limited to feed oil containing about 0.001% by weight soap. In addition, phosphatides are limited to about 90 to 100 ppm in oil because phosphatides react with nickel catalysts to inhibit selectivity and hydrogenation rates. The present invention can be applied even when both soap and phosphatide in large quantities, and at this time, the oil is quickly and efficiently hydrogenated.

Example 2

Another reactant of alkaline refined soybean oil obtained from commercially available crude products was hydrogenated according to the invention to make stearin products. Supply oil analysis is as follows.

Soap 0.11 wt% C 16: 1 0.2

Phosphatid 4.0ppm C 17: 0 0.2

Iron 0.25 ppm IsoC 18: 0 Trace

Free fatty acid 0.06 wt% C 18: 0 3.8

Hue (Lobby Bond) 4.9R-50Y C 18: 1 21.4

Fatty acid analysis Fatty acid (% by weight) C 18: 2 53.9

C 14: 0 0.1 C 18: 3 8.7

C 15: 0 Trace amount C 20: 0 0.4

Iso C 16: 0 Trace C 22: 0 0.2

C 16: 0 11.1

The calculated yod price is 134.7

A series of six soybean oils consisting of 1300 g of soybean oil was hydrogenated under the following hydrogenation conditions.

Temperature 220 ~ 255 ℃ Stirring 700r.p.m

Pressure 60p.si. 0.025% Nickel by weight of catalyst

1.0 wt% copper chrome steel

By periodically taking an oil sample and analyzing it, the reaction time required to reach an iodide of 50-70, about 30 and about 0 was measured.

The results in the table clearly show the reproducibility of the present invention in the hydrogenation of oils, demonstrating that stearin products are prepared quickly, even from relatively soapy oils. The copper chromium steel cocatalysts of operations 1 and 3-6 were stabilized with barium oxide and those of operation 2 were not stabilized.

Example 3

Another reactant of the oil of Example 2 was hydrogenated only with a nickel catalyst and a copper chromium steel cocatalyst. Hydrogenation conditions were substantially the same as the operation of Example 2 as follows.

The cocatalyst of operation 2-5 is stabilized with barium oxide and the guard catalyst of operation 1 is not stabilized.

The results in the above table show the superiority when a combination of nickel catalyst and copper chrome steel is used for hydrogenation of oil. Note that the oil is unable to hydrogenate iodine below about 100 with copper chromium steel cocatalysts. Soap degrades the reaction even when using a relatively high concentration of cocatalyst of 1.0% by weight. Nickel catalyst operation exhibits an extremely prolonged hydrogenation time for the production of stearin products. The hydrogenation process of the present invention can produce stearin in a few hours and show such a result even in the presence of contaminating soap. Furthermore, the comparative time of hydrogenation to obtain stearin was tested with pure oil (0.001-0.003% soap or less) using 0.1 wt% nickel catalyst and the results of the present invention using relatively soap-contaminated oil. By comparison.

Example 4

The soybean oil described in Example 2 was hydrogenated according to the following known method.

a) Paterson, US Patent No. 2,357,352

b) Moulton, US Pat. No. 2,856,710 and

c) high oleic oils by selective hydrogenation of popescu and soybean oil JAOCS 46; 97-99 (1969) The results of the above operations and the results of Examples 2 and 3 are described below.

Hasman's fourth operation is the average of the six operations described in Example 2. The fifth operation of nickel is the average of the results described in Example 3.

1 shows the results graphically. It can be readily seen from the above that the method of the present invention first reduces the iodine value of the oil to about 0 (feed oil contaminated with 0.1% soap). More importantly, however, is the hydrogenation rate (change in iodide per hour) per process. FIG. 2 shows the hydrogenation rate according to the nickel content in the catalyst system at a constant value of 1.0% copper-chromium steel cocatalyst. (Note; Patterson's result is 0.2 because copper-chromium steel device is not 1.0%. Omit it because it is%.)

The rate is calculated based on the final hydrogenated iodine of 79.6 (the final measurement that can be reached in all processes).

The rate is the final change in the total iodine from feed iodine 135 (measured iodine 134.7 chemical iodine 136.2) to final iodine 79.6 (lowest iodine that can be reached in all methods, as in Figure 1). Calculated by dividing by the total time taken until 79.6. This rate accelerates the reaction as the nickel level increases below the average hydrogenation rate for certain copper-chrome steel units where only nickel levels are adjusted for feed oils containing 0.1% by weight soiled soap, but so rapidly at nickel levels above 0.02%. Does not increase.

Example 5

In order to find out the drop effect of soap in general and the inventors' ability to suppress the effect in the hydrogenation process, the next hydrogenation operation was carried out in soybean oil almost completely removed by soap.

The reprocessed soybean oil is analyzed as follows.

Supply soybean oil

Moisture 0.0% Free Fatty Acid 0.07%

Soap 0.003% Chemical Iodine 136.2

Iron 0.25ppm Color 4.1R-50Y

Phosphatid 2.0ppm

The hydrogenation operation conditions are as follows.

Supply 1300 grams Pressure 60 p.s.i (hydrogen)

Temperature 210 ~ 225 ℃ Stir 600/700 r.p.m

The result of the hydrogenation operation is as follows.

Nickel No. 2- Average of 4 operations of Example 3

Average of six operations of Hasman No-Example 2

The result of the said operation is shown in FIG. The results indicate that hydrogenation of almost pure oils can be performed only with nickel catalysts, and the copper-chromium steel cocatalyst contributes little, but the concentration of contaminated soap in the feed oil is about 0.1-0.25% by weight (catalyst / cocatalyst system). The copper-chromium steel co-catalyst increases the copper-chromium steel catalyst value depending on the soap concentration in the feed oil. It is almost suppressed by adjusting well.

[Introduction of Examples 6 and 7]

The feed oil used in Examples 6 and 7 is an alkaline refined soybean oil obtained from the cooking oil purification process. The analysis of a representative feed oil of all the oils used herein is described below.

All hydrogenation operations were carried out in a 2-liter pressure vessel equipped with an agitator capable of stirring at various speeds, a pressure gauge and an electric heater. In the first stage, the feed oil and the catalyst were put into a vessel where the air was evacuated and the inside thereof was preheated to 100 ° C, and the first stage hydrogenation was performed. After the first stage the catalyst was removed from the oil and a new catalyst was added for the second hydrogenation. Iodide (IV) was measured and the sample for analysis was taken periodically. In primary hydrogenation, the reaction conditions are 100-230 ° C. and hydrogen pressure 40-60 psi.

Similar conditions apply for secondary hydrogenation but with temperatures in the range of about 200 to 250 ° C. The cocatalyst is a copper-chromium steel stabilized with barium oxide 7-8% (by weight of the cocatalyst) (the molar ratio of copper to chromium is about 1: 1). (Supplied by Calasicat Division of Mallinckrodt.InC. Code 102 and Code 108 copper chromium steel catalysts; and Code 477A-26-3-21P copper chrome steel catalysts supplied by Harshaw Chemical Company. The nickel catalyst is fully active on the support and protected in stearin.

(* NYSELHK-4 nickel catalyst supplied by Harshaw Chemical Company)

Example 6

Commercially refined soybean oil, similar in composition to the oil described above, was hydrogenated in a two step process in accordance with the present invention.

Through the previous operation, 0.025 wt% nickel hydrogenation catalyst and 1.0 wt% copper-chromium steel cocatalyst are used in the first hydrogenation stage, while 0.1 wt% nickel hydrogen catalyst is used in the secondary zone. In operation 1-5 the oil contains about 0.003% by weight of soap and in operation 6 it contains 0.11% by weight. The intermediate iodine value during the first hydrogenation step varies as described in Table 1 below, which summarizes the results.

TABLE 1

The results in the table above show that the hydrogenation time for producing stearin by this method is very short. Operation 6 in particular is important because it produces stearin in a surprisingly fast way, even in oils that are heavily soapy, indicating that this method is flexible.

4 is a diagram showing the results of Table 1. Except for operation 6, where soap is highly contaminated oil, operations 1-5 show an interesting trend: higher iodine values at the end of the first hydrogenation stage lead to zero iodine. The total hydrogen addition time to reach -3 is shortened.

Article 5 plots the intermediate iodine value for the total hydrogenation time for iodine up to 3 in operations 1-5.

The bending point on the curve that minimizes the total hydrogenation time is clearly shown in FIG. Surprisingly, the flexion point occurs at relatively high iodine values corresponding to a short first hydrogenation time. The short hydrogenation time from the first zone to the bend point using the extremely active nickel / copper chromium steel catalyst combinations in two stages includes a second stage using only one less active, soap-sensitive nickel hydrogenation catalyst. Shorten the total hydrogenation time.

Another unexpected advantage shown in FIG. 4 is that the rate of hydrogenation in the secondary zone using only nickel catalyst increases dramatically with the use of the first hydrogenation step, which increases at higher intermediate iodine rates. Table II shows the hydrogenation rate obtained in operation 1-5. All speeds are changes in iodine per hour.

TABLE II

Looking at the above table, it can be seen that the method of operation 2 has the maximum change in the iodine value per hour, that is, the speed. This result shows that the hydrogenation rate is extremely high when only the nickel-hydrogen catalyst is employed in the secondary zone, and the operation rate is the highest and the total hydrogenation time is the shortest. It is thought that results similar to those listed in the table above are also found in oils more contaminated with soap, except that the bending point (maximum point in the middle IV) decreases rapidly with increasing soap contamination.

The upper limit of this range is most suitable, although the range of intermediate iodine values that the method can perform well is wide.

Example 7

In each case, various comparative hydrogenation operations were performed using various soybean oils containing about 0.003% by weight of contaminated soap.

The method and catalyst used were summarized as follows.

A. Two-stage hydrogenation with alternating order of catalyst system in Example 6, i.e. 0.1 wt% nickel catalyst in the first stage and nickel / etc-chromium steel catalyst (0.025 / 1.0 wt%) in the second stage . The average of seven operations was reported.

B. The average of one step hydrogenation, four operations using only 0.1 wt% nickel hydrogenation catalyst was reported.

C. One stage hydrogenation using 0.025 wt% nickel catalyst and 1.0 wt copper-chromium steel cocatalyst.

C. The average of two operations, two steps of hydrogenation using 0.1% by weight of fresh nickel catalysts, was reported for each step.

The result obtained from the said hydrogenation operation was shown by FIG. 6 with operation 2 of Example 6, and was shown.

(Operation 2 is the best operation method of the present invention)

There are some improvements in the hydrogenation step using only nickel hydration catalysts. Nickel catalysts are inert by contaminated soaps, so all hydrogenation processes are advantageous only if the new nickel catalyst is used several times. Even so, however, the hydrogenation time and rate (most significant in the second stage) are not as advantageous as the present invention. When the order of the catalyst systems is reversed in two steps, as shown in operation A, the same result as obtained in the present method is not obtained.

In addition, when only the nickel-hydrogen catalyst is used (the first stage is 0 hours and only the second stage) and when the nickel-copper steel catalyst combination is used, the second stage time is 0 hours and only the first stage is used. Only use) did not yield results equivalent to those obtained in this method as in operations B and C.

The superiority of the present invention is excellent as the contaminated soap value in the feed oil is increased. Comparative hydrogenation operations were performed using soybean oil, each containing about 0.11% by weight soiled soap.

One step hydrogenation using B ′ 0.1 wt% nickel catalyst (average of four operations described in Example 3)

P. Hydrogenation using 0.1 wt% copper-chromium steel catalyst (average of 5 operations described in Example 3)

The result obtained from the said hydrogenation operation and the result of operation 6 of Example 6 were shown in FIG. 7 and shown.

Operations B and B 'are almost identical in procedure except for increased soap contamination in the feed oil, but the results are very different. The effect of the contaminated soap on the hydrogenation time was so great that the hydrogenation time up to zero of iodine was about 1.2 hours in operation B and increased to about 10 hours in operation B '. However, the hydrogenation time in the present invention is increased from about 0.467 hours of operation 2 to about 1.25 hours of operation 6. In the present method, since the iodine value is 30 or less, the hydrogenation rate is also almost constant, or it can be seen that the hydrogenation rate is decreased and thus the time is increased in operation B '.

The multistage supply of nickel catalysts in operation B 'can shorten the total hydrogenation time, but it is not certain until about 5-6 hours. Operation P indicates that under the hydrogenation conditions of the present invention, the copper-chromium steel catalyst alone cannot catalytically hydrogenate the feed oil to less than about 100 yds to a significant degree and the hydrogenation time will also be out of tolerance. have.

The results point out not only the superiority of the method but also the unexpected superiority.

Using this method, stearin can be produced very quickly, even in oils with severe soap contamination.

At a given soap value, the intermediate iodine value is optimal at the end of the first stage where the hydrogenation time is minimized and the total hydrogenation rate is maximum, and the hydrogenation rate in the secondary zone is dramatically increased and maximized. appear.

Claims (1)

In the hydrogenation of glycerides in the hydrogenation zone with hydrogen gas under hydrogen catalyst conditions in the presence of at least 0.02% nickel hydrogenation catalyst and at least about 0.25% copper-chromium steel cocatalyst based on the weight of glyceride oil The concentration of the oil contaminated with soap is at least a minimum to cause a dropping effect and is not excess than about 0.25% by weight of the oil, the concentration of the cocatalyst is broadly defined and maintained in proportion to the concentration of the soap, at least the oil The hydrogenation is stopped after the saturation of the saturation is significantly increased.

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