SU1414316A3 - Method of separating a mixture of oleic and linoleic acids - Google Patents

Abstract

The invention relates to carboxylic acids, in particular to the separation of oleic and linoleic acids. The purpose of the invention is to increase the degree of separation of the mixture. Separation is carried out by passing the initial mixture through a column with an adsorbent. As the latter, a neutral molecular sieve containing 77% silicalite and 23% amorphous silica was used, with a particle size of 20-50 mesh, obtained by mixing silicalite powder and colloidal silicon dioxide. The resulting mixture is dried and calcined in air for 48 hours to remove hydroxyl groups. The separation process is carried out at 60-120 ° C, the pressure required to keep the mixture in a liquid state, to form a raffinate containing linoleic acid. The subsequent desorption of oleic acid is carried out with a desorbent containing 80% methyl ethyl ketone and 20% propionic acid or acetone, or 85-90% acetone and 10-15% n-hexane or methyl ethyl ketone. 4 ill., 3 tab. g w c

Description

four

:,about

SG5

 cm

This invention relates to a process for the separation of a mixture of oleic and pinoleic acids, which can be improved in the chemical: chemical industry.

The purpose of the invention is to increase the degree of times, the whole: e1sh. mixes.

PA of FIG. 1 shows a device for carrying out the inventive method, FIG. 2-4 - graphs illustrating the method.

EXAMPLE 1. A unidirectional flow of liquid flows through all sections of the column, the composition and flow of which differ in its different points. In column 1 there are zones 1, II, III, and IV. The system consists of a manifold-distributor 3, a pump 2, which supports the support of the liquid in the column, a pipeline 4 connected to the tank 2, and inlet and exhaust pipelines passing through the system of the collector apr ate tel.

The containment zone (zone T), determined by the molecular sieve, is located between the inlet stream 5 of the initial mixture and the outlet stream 6 of the raffinate. In this zone, the initial mixture is in contact with the molecular sieve, the extract components are held last, and the raffinate stream passes further; in the direction opposite to the inlet mixture, and then, the flow into the total stream is condensed. An industrial stream (diluent) may be introduced into zone I at the point located at the southern end of the feed stream,

 Above upstream, immediately after zone I between: the outlet stream of extract 7 and the inlet stream 5 of the initial mixture, zone II. purification, as determined by the molecular sieve. The purification is carried out by passing part of the stream 8 of the extract that is removed from zone III to zone II at the top, its boundary. Zone III is prefilled with a molecular sieve and is intended to inlet the extrusion of the liquid extract. Zone IV is buffered and is designed to preserve the amount of displacing fluid.

The temperature of the liquid stream is 60 ° C, the flow in the column is ascending at a flow rate of 1.2 ml / min. The initial flow consists of 10% by weight of a mixture of lardic acids and 90% by weight of the liquid vortex. Mixture of fatty acids

0

five

five

0

0

five

0

five

0

five

consists of linoleic and oleic acids in the ratio of 50:50. The column is filled with bound Lyudox-grade silica (23 wt.%) Silicalite (77 wt.%), Which is prepared in a manner that includes gelation by removing water (drying) followed by treatment, resulting in the removal of hydroxyl groups, which carried out by heating in air at 1000 ° & within .48 hours. The molecular sieve obtained is then crushed and sieved through a 20-50 mesh sieve. The displacing liquid used contains 80 vol.% Methyl lithium ketone and 20 vol.% Propionic acid.

The results of separation of the mixture of oleic and linoleic acids in Example 1 are shown in FIG. 2. From FIG. 2 it is clear that the separation of oleic acid from linoleic acid is clear and distinct, however, the kinetics of desorption is somewhat weaker, as can be seen from the large total. retention, which includes the volume of the displacing fluid. . The curves obtained indicate that there are no traces of activity between the adsorbent and the components of the initial mixture, which was previously observed with the use of silicate with an organic binder and silicate with a silica binder that is not subjected to heat treatment according to the present invention.

Example 2: Conduct an HPie section using the same hardware as described above, operating in pulsed mode. The temperature of the liquid is 80. C, the flow in the column is directed downwards. At a flow rate of 1.2 ml / min. The initial mixture flow consists of 10% by weight of tall oil and 90% by weight, displaced by suction liquid. The column is filled with a Ludox brand of amorphous silica (23 wt.%) Silicalite (77 wt.%), As in Example 1. The used displacement fluid is 100% acetone.

The results obtained in this example are shown in FIG. 3

As can be seen from the graph in FIG. 3, the separation of resin acid, oleic acid, and linoleic acid is clear and distinct, but the kinetics of desorption is also rather low.

Example 3. The separation is carried out in the same way as in Example 2, since that time that the displacing fluid has

314

the polarity index is more than 3.5, the temperature of the 7 FLUID in the column is.

The results obtained in this example are shown in FIG. four.

As can be seen from the graph in FIG. 4, a clear improvement (increase) in desorption is observed, which is manifested in a decrease in the retention volume.

Example 4 A silicate sorbent is used in a fluid bed device for separating oleic and linoleic acids. This device contains 24 fixed, interconnected layers. Four layers consist of 24 pieces of pipes 300 mm long with an inner diameter of 300 mm. Each layer contains 19.2 mm of adsorbent — a molecular sieve with particles, 95% by weight passes through a sieve with 0.250 mm openings and is retained on at least 98% by weight on a sieve with 0.590 mm openings. These particles are obtained by mixing equal parts of silicate powder and Lukodec brand colloidal amorphous silica, drying and heat treating the particles for 48 hours at 1000 C. In the resulting adsorbent silicalite composes 77 wt.% And silica 23 wt.% Each the layer communicates with the adjacent ones in such a way that the opening in the upper part is the outlet for it and the entrance for the upper one.

For process and industrial streams, four supply and output lines are provided (for feeding a separable mixture, for removing the raffinate, for feeding desorbent and for extracting the extract), as well as a line connecting the corresponding openings of the central distribution valve for the continuous stream, with line, feed-. common source mixture from distribution valve c. separation column.

The distribution valve has 24 windows connected by 24 lines of the same length with all 24 fixed layers of the adsorbent. This valve controls the addition and removal of the original product, desorbent, washing medium, raffinate and extract in such a way that each

the layer can be fed with separate streams of desorbent, initial product and industrial medium, or separate streams can be drawn from each layer

6

raffinate, extract and flushing medium by turning the valve.

The initial mixture of 8.2 ml / h of linoleic acid and 3.8 ml / h of oleic acid is loaded into layer 9. During the addition of the initial mixture to layer 9, a stream of 100% acetone is fed to layer 23, with a flow rate of 186 ml / h When loading the initial mixture and the adsorbent into layers 9 and 23 from layer 1, withdrawal of raffinate at a flow rate of 38 ml / h and from layer 16 — extract with a flow rate of 160 ml / h. The content of linoleic and oleic acids in the raffinate and extract streams is described more fully below. In this experiment, the flushing stream was not used.

All points of introduction and removal are switched on by means of a distribution valve for eluent so that each stream completes the cycle of operation throughout the column for 60 minutes. When circulating the initial mixture, raffinate, desorbent, extract and continuous flow through the layer inside the column, an overpressure of 1300 kPa is maintained and temperature The fluid continuously circulates through each zone as the pseudo-mobile adsorbent is carried out. The net fluid flow through the column in each of the four zones:

Zone Fluid flow rate, ml / h

57

45

205

334

After 208 hours of operation, the raffinate and extract streams yield components at volumetric rates given in Table. one.

Loss of components between inlets and outlets is attributable to leakage and evaporation from open collection tanks.

- The initial ratio of linoleic acid to oleic acid in a mixture of 2.1: 1. After processing the initial mixture in a device with a pseudo-moving layer, the linoleic ratio. acids to oleic acid in the raffinate and extract streams, respectively, 5.21:: 1 and 0.312: 1.

Example 5. The process begins with the loading of a mixture of linoleic acid at a rate of 5.2 ml / h, oleic acid514

lots at a rate of 4.3 ml / h and acetone at a rate of 9.5 ml / h into layer 9. At the time of feeding into layer 9, layer 23 is fed with a stream of desorbent (acetone) with a speed of 172 ml / h and n-hexane with a speed 19 ml / h. As the feed mixture and desorbent from layer 1 is fed to layers 9 and 23, the raffinate is withdrawn at a flow rate of 59 mp / h and from extracting bed 18 - an extract with a flow rate of 156 ml / h. The content of linoleic and oleic acids in the raffinate and extract is indicated below. In addition to the main introduction of the desorbent into the desorption zone, the desorbent at a rate of 5 ml / h is fed to the washing column of the line to which the raffinate was previously fed.

All inlets for inlet and outlet are opened by means of a distribution valve, moving the desorbent bed in such a way that each flow makes a working cycle through the column for 60 minutes. When circulating through the bed of the initial mixture, raffinate, desorbent, extract, and a continuous stream inside the column, an overpressure of 1550 kPa and temperature are maintained. The net flow of fluid through the column in each of the four zones:

Zone Fluid Flow, ml / h

2-40

3

four

116 -334

After 268 hours of operation, the raffinate and extract streams yield components at volumetric rates given in Table. 2

The loss of components between inlets and outlets is attributable to leakage and evaporation from open-pack tanks.

The initial ratio of linoleic acid to oleic is 1: 21: 1. After processing the initial mixture in a pseudo-mobile bed adsorption device, the ratios of linoleic acid to oleic acid in the raffinate and extract streams are 3.23: 1 and 300: 1, respectively.

Example 6. Begin the process

from loading a mixture of linoleic acid at a rate of 5.7 ml / h, oleic acid at a rate of 3.8 ml / h, and acetone at a rate of 9.5 ml / h in layer 9.

Mr. Yu 5

20 to 25 - th

.

0

45

50

55

6 6

During the supply of the initial mixture to layer 9, a stream of desorbent is charged to layer 23 at a rate of 142 ml / h and n-hexane at a rate of 25 ml / h. As the layers 9 and 23 are fed from layer 1, the raffinate is released at a rate of 61 ml / h, and from layer 18 - an extract at a rate of 138 ml / h. The content of linoleic and oleic acids in the raffinate and extract streams is shown below. In addition to the main supply of desorbent to the desorption zone, acetone is supplied at a rate of 13 ml / h to the washing column of the previous raffinate feed line, which can otherwise contaminate the extract stream from the very beginning.

All inlets and outlets are simultaneously opened by means of a distribution valve in order to create movement of the bed of adsorbent in such a way that each flow completes the working cycle through the column for 60 minutes. During the circulation of the initial mixture, raffinate, desorbent, extract, and night flush through the layer inside the column under, an excess pressure of 2110 kPa and a temperature of 120 ° C is maintained. The net flow of fluid through the column in each of the four zones:

Flow Flow Zone

Wednesday ml / h 1. -7.0

. 2-39,0

399.0

4-334.0

After 48 hours of operation, the raffinate and extract streams were given the following components at volumetric rates given in Table. 3

PRI me R 7. Begin the process with the filing of the initial mixture of linoleic acid at a rate of 3.53 ml / h, oleic acid at a rate of 1.51 ml / h and acetone at a rate of 95.96 ml / h into layer 9. In the time of feeding the initial mixture to layer 9; layer 23 is supplied with a stream of methyl ethyl ketone desorbent (100%) at a rate of 270 ml / h. As the initial mixture and desorbent are fed into layers 9 and 23 from layer 1, withdrawal of raffinate t. speed of 227 ml / h, and from layer 18 - extract with a speed of 150 W / h. In addition to the basic α-desorbent delivery, acetone is also fed to the desorption zone at a rate of 6 ml / h to flush the raffinate’s previous feed line.

 u

All inlets and outlets are simultaneously shifted at regular intervals by means of a distribution valve in order to create a movement of the desorbent bed so that each flow performs a full working cycle through the column for 60 minutes.

During the circulation of the initial mixture of ci, raffinate, extract of desorbent and wash stream through the layer inside the column, an overpressure of 2,760 kPa and a temperature of 120 ° C are maintained. The net flow of fluid through the column in each of all four zones:

15

Fluid flow, ml / h 123 16 166 -334

After 189 hours of operation, the raffinate stream contained 80.8% pure linoleic acid, and the extract stream contained 83.3% oleic acid.

43168

Claims (1)

Claims A method of separating a mixture of oleinopic acid and linoleic acid by passing an initial mixture through a column with an adsorbent, characterized in that, in order to increase the degree of separation of the mixture, a neutral molecular sieve containing 77% silicalite and 23% amorphous dioxide is used as an adsorbent 20-50 mesh, obtained by mixing silicalite powder and colloidal silicon dioxide, drying and calcining the mixture for 48 hours in air to remove hydroxyl groups, and the separation process in travel at a temperature of 60-120 ° C, the pressure required to keep the mixture in a liquid state, to obtain a raffinate containing linoleic acid, and subsequent desorption of oleic acid using a desorbent containing 80% methyl ethyl ketone and 20% propionic acid or acetone, or 85- 90% acetone and 10-15% n-hexane or methyl ethyl ketone. Table 1 five 0 five table 2 4.9 0.7 1, 2.3 /Flow J, / 9 / (CJ7jffaf (/ ji, l OflSfff / rr Pawuffam fe / Table 3 40.0 122.9 9.8 14,5 60 one W fB 7296120 / "4 Total Holds Figure 2 go ifO 60 in 100 120 t . volume {/ der and & ants Fig.Z t 160 1VO QO. 100 120 t 160 OSuitff / volume y fHt / ffoMuff figM 1ВО