CS209695B1 - Method of hydrogenation of non-saturated aliphatic acids esters - Google Patents

Description

The present invention relates to a process and a hyalphene gene of fatty acid esters on nickel cp and l-zinc.

Hydrogenation of fatty acid esters is used to improve the properties of vegetable fats and oils. It is known that the hydrogenation of these compounds can be carried out using heterogeneous catalysts such as nickel on alumina. A disadvantage of these processes using said catalysts is the relatively low efficiency and selectivity of this type of catalyst and the need for hydrogenation at relatively high temperatures. The use of higher temperatures (on the contrary) greatly reduces the selectivity of the reaction, i.e. the conversion of the initial hydrogenated species to the compounds or compounds of the desired chemical composition.

It is known from the literature that some transition metal complexes VIII. The groups act as catalysts for the hydrogenation of unsaturated compounds. Jones: Homogenous Hydrogenation, J. Wiley, N.Y. 1971]. In particular, the Ziegler type nickel catalyst is highly effective for hydrogenating esters of unsaturated fatty acids / Jap. U.S. Pat. prihl, No. 21 082, Fr. U.S. Pat. C.

258 896, DOS No. 2 503 486 /.

While these catalysts are characterized by a higher selectivity compared to the prior art heterogeneous catalysts due to the formation of undesired trans-isomers in the possibility of operating at lower temperatures, the homogeneous nature of these catalyst systems causes difficulties, particularly in poor removal of catalysts from the product. their bad recycling.

These disadvantages are overcome by the process of hydrogenation of unsaturated fatty acid esters having 1 to 3 C = C double bonds and a carbon chain of 12 to 22 carbon atoms, preferably glycerides of these acids in the presence of a nickel catalyst on an inorganic carrier according to the invention. characterized in that the reaction is carried out with a catalyst prepared by modifying 20 to 100 parts by weight, parts of said carrier 1.5 to 75 parts by weight, triethylalan or diethyl chlorine and treating with 1 to 2 parts by weight, b.is/butylsalkylaldimino (nickel) II) at a temperature of 10 to 150 ° C and a hydrogen pressure of up to 2 MPa while the hydrogenation is carried out in hydrocarbon solvents, preferably in n-hexane, n-heptane or petroleum ether.

The preparation of conventional nickel catalysts on an inorganic support consists in adsorbing the nickel salt to the OH groups of the inorganic support and then reducing it to nickel by either hydrogen or an organoaluminum compound.

Using the process according to the invention, the inorganic carrier, preferably alumina or aluminosic acid, is first modified with an organic aluminum compound, and then the modified carrier is treated with an organic divalent nickel compound to form a directly active catalyst suitable for direct use in hydrogenation. Cotton, rapeseed or soybean oil is used as the hydrogenic material.

Using the process according to the invention, it is possible to operate at lower temperatures than with heterogeneous catalysts. This process results in a lower percentage of transsaturation, while at the same time providing the possibility of regenerating the catalyst and hence recyclable.

The invention is further elucidated on the basis of examples, without being limited thereto.

Example 1

У - ΛΙτΟ ^ / ΙόΟ ml. particle size 0.3-0.6 mm) was heated to 400 ° C for 6 h in an argon stream (20 L) and held for an additional 16 h at this temperature. The sample was then washed with a solution of 80 ml of triethylalan in 160 ml of n-hexane first at -20 ° C, and then at room temperature (1.5 h). The surface-modified support was then washed with n-hexane and dried at 25 ° C with argon; 80 ml of this support was washed with a 4 mM solution of bis (n-butylsalicylaldiminato) / nickel (II) in 300 ml of toluene at -80 ° C and allowed to react for 2.5 h. The solvent was decanted from the catalyst, the catalyst was washed again with toluene and dried under vacuum at room temperature.

Example 2

The Al / C2H5 / 3 modified support was prepared in the same manner as in Example 1; 80 ml of a sample of this support was placed in a warm 4 mM solution (ca. 60 ° C) of bis (n-butylsalicylaldiminato) / nickel (II) in 300 ml of hexane, allowed to react, decanted and dried as in Example 1.

Example 3

200 ml of aluminosilicate containing 22.7, SiO2 (particle size 0.3 to 0.6 mm) was dried in argon according to Example 1. This support was reacted with 95 ml of diethylchloralan in 155 ml of n-hexane first at -20 ° C. and then at room temperature for 1.5 h. The resulting material was washed, dried and reacted with a solution of bis (n-butylsalicylaldimino) (nickel) (II) in toluene as in Example 1.

EXAMPLE 4 ml of an aluminum / C2H5 / 2Cl modified alumina carrier as in Example 3 was reacted with a bis (n-butylsalicylaldiminato) / nickel (II) solution according to Example 2.

Example 5

The reaction vessel was charged with argon and 1 part by weight of the catalyst of Example 2 and, after evacuation, the reactor was charged with hydrogen. After addition of 12.5 parts by weight. With a 30% solution of soybean oil in n-heptane, the reaction mixture was stirred (1200 rpm) at room temperature until the hydrogen pressure dropped from 13.3 MPa to 11.3 MPa. After removal of the catalyst by filtration, 12.5 parts by weight of a soybean oil solution was introduced into the reaction vessel and hydrogenated as described above. This procedure was repeated 5 times. The results of the procedure are summarized in Table 1.

Example 6

The reactor was charged under argon with 1 part by weight of the catalyst the preparation of which was described in Example 1 and, after evacuation, filled with hydrogen by adding 4 parts by weight of rapeseed oil. Hydrogenation was performed in the same manner as in Example 5 and repeated with a separate catalyst 3 times. The results are summarized in Table II.

Example 7

Hydrogenation was carried out as in Example 6, except that solvent-free rapeseed oil was used

12.5 parts by weight 30% rape seed solution

is in n-heptane and the reaction was catalyzed complex according to example 3, Acquired product had composition: C 16 í 0 5.7 Z C 18 : 0 2.6 7 0 18: 2 16.2 7. C 18 : 3 2.0 7 0 18: 1 70.4% C 2 2: 1 2.9% Ex. í k 1 and d 8 The reactor was filled 1 part. c.! ” ki ti- ^T i ^b u ^{l k} l AND

of the lysator of Example 4 and after evacuation and filled with hydrogen and 4 parts of hmoo. soybean oil of the same composition as in Example 5 was hydrogenated at room temperature for 26 min. The product obtained had the following composition:

C 16 í : 0 10.4% C 1 8: : 0 6.5% 0 18: : 28856% 0 18: : 3 ,, 9% C 18: : 1 42.7 W

Folders

Soybean oil

Hydrogenated soybean oil composition (% w / w) for cycles 1 to 5

2 3 4 5

C 1 6; : 0 10.4 11.2 11, 3 1 1,5 1 1,2 11.0 C 18: : 0 4.2 6.7 6.8 7.0 6.9 6.5 C 18: i 1 23, 6 43, 3 45.0 42.3 43, 2 43, 2 C 18: : 2 54.3 36.7 34, 9 36.6 36.1 3 6,7 C 18: : 3 7.5 2, 1 2,0 2.6 2, 6 2.6

Table II

Folders

Rapeseed oil

Composition of hydrogenated rape oil (% HeioU) in cycles 1 to 3

1 2 3 C 1 6: : 0 5.7 5.5 5.9 4,5 0 18: : 0 1, 9 2.5 2.4 2, 9 0 1: : 1 58.4 7 1.6 7 1, 3 73.4 C 18: : 2 21, 1 15.1 15.1 13, 2 C 18: : 3 13.0 2.2 1, 7 1 M 0 22; : 1 2, 9 2.9 3, 6 3, 6

SUBJECT

Claims (1)

SUBJECT A process for the hydrogenation of unsaturated fatty acid esters having 1 to 3 C 2 double bonds and a carbon chain of 12 to 22 carbon atoms, preferably glycerides of these acids, in the presence of nickel-based catalysts on an inorganic catalyst, preferably alumina. aluminate or alumina, characterized in that the reaction is carried out with a catalyst of 20 to 100 OF THE INVENTION Pot Parts. said carrier 1.5 to 75 parts Umo. triethylamine or children with 1 to 2 parts of Umot, hitting / n-butyl and faceted lald 101пп1о / пП kku // I / at temperature 10 to 150 ° C and hydrogen pressure up to 2 MPa, the hydrogenation being carried out. in hydrocarbon solvents, preferably n-Uexin, n-UepOan or petroleum / lethet,