FR2472952A1 - NICKEL BASED CATALYST FIXED ON A SUPPORT AND USE OF THE CATALYST IN A HYDROGENATION PROCESS OF POLYUNSATURATED ORGANIC COMPOUNDS TO THE PARTIALLY OR COMPLETELY SATURATED COMPOUNDS - Google Patents

Abstract

A NICKEL-BASED CATALYST FIXED ON A MINERAL SUPPORT SUCH AS DIATOMA EARTH, ALUMINA OR SILICA GEL CONTAINS 10 TO 85 NICKEL WEIGHTS OF WHICH 40 TO 99 ARE IN METAL NICKEL AND 0.05 TO 6.7 BY WEIGHT OF BORON, WITH POSSIBLY 0.1 TO 10 BY WEIGHT OF COPPER, SILVER, CHROMIUM, ZIRCONIUM, THORIUM, TIN, RHENIUM, A METAL OF GROUPEVIII OR OF ONE OF THEIR MIXTURES; A PROCESS FOR HYDROGENATING POLYUNSATURATED ORGANIC COMPOUNDS TO THE CORRESPONDING PARTIALLY OR COMPLETELY SATURATED COMPOUNDS USING SUCH A CATALYST IS ALSO DESCRIBED.

Description

The present invention relates to a catalyst based on

nickel fixed on a support, a process for preparing this cat-

  lyser and the use of this catalyst in a hydro-

generation of polyunsaturated organic compounds into corresponding partially or completely saturated compounds. Nickel catalysts fixed on a support such as diatomaceous earth, alumina or silica gel have long been used as heterogeneous catalysts

in processes for the selective hydrogenation of organic compounds

  polyunsaturated nicks in the di- or monosaturated compounds cor-

  respondents. One of the most important of these processes is the hy-

  drogenation of the combined unsaturated fatty acids in vegetable oils and animal fats or the hydrogenation of free unsaturated fatty acids, into the corresponding partially or completely saturated compounds. To date the total global amount of oils and fats that are hydrogenated

  and then transform them into food and tech-

  more than 4 x 106 tonnes. This fact, as well as

  efforts to make maximum use of all resources

  these foods, oblige producers to improve the hydrogenation technology according to which in addition to obtaining the optimal economic effect, one must operate according to

a selective mode.

Due to the boiling points of the materials

  work, hydrogenation is carried out in liquid phase at

rature and at high pressure in the presence of a heterogeneous catalyst

  homogeneous so that there is a three-phase liquid system-

relatively complex gas-solid. Outside the parameters

  equipment, such as function

  continuous or discontinuous operation, the mode of mass transfer and heat transfer in the system, etc., the quality of the catalyst used is of paramount importance. To make full use of the capacity of a hydrogenation unit, it is necessary to operate at a high reaction rate

  and therefore to use a high activity catalyst.

  To obtain a product with the required composition,

  of predetermined esters of fatty acids, it is also

  very important that the hydrogenation catalyst has a

selective wear. For example in the hydrogenation of vegetable oils such as rapeseed oil or soybean oil which contain glycerides of linolenic acid, it is necessary, in order to increase the consistency of the flavor and odor of the product, to strongly or completely eliminate the glycerides of linolenic acid while reducing as little as possible the glyceride content of linoleic acid and minimizing the glyceride content of stearic acid. Generally, the nickel catalysts used to date in practice do not exhibit both a high activity and a high selectivity for hydrogenation of polyunsaturated organic compounds and generally only one of these.

properties predominates.

The invention relates to an improved nickel-based catalyst fixed on a mineral support such as diatomaceous earth, alumina or silica gel, consisting of 10 to 85% by weight of nickel, of which 40 to 99% consist of

  metallic nickel and from 0.05 to 6.7% by weight of boron. The ca-

talyseur of the invention may further contain from 0.01 to 10% by weight of copper, silver, chromium, zirconium, thorium, tin, rhenium or one of the metals of the group

  VIII or a mixture of at least two of these metals.

  This catalyst is prepared as follows (1) a suspension of an inorganic support is precipitated in a solution of a nickel salt with an alkali, (2) the mixture of the inorganic support and the precipitate of nickel dihydroxide is subjected and / or basic nickel carbonate having the composition NiCO3.x Ni (OH) 2.y H20, o

  x is a number from 1 to 30 inclusive and y is any number

  conch, to the action of a solution of an alka borohydride

  flax at a rate of 0.005 to 1.25 mole of borohydride per mole of nickel, by carrying out this operation at a temperature between 20 and 1000C and a pH greater than 10 for a period of 5 to 60 minutes, (3) washed and the mass obtained is dried, (4) the mass is calcined at a temperature between 300 and 5000C and (5) the calcined mass is reduced at a temperature

  between 250 and 4800C with a degree of reduction between-

be 0.40 and 0.99.

  When it is necessary for the nickel-based catalyst fixed on a support to contain the aforementioned modifier metals, the mixture of an inorganic support and of nickel dihydroxide and / or basic nickel carbonate having the above composition is treated with plus a salt of copper, silver, chromium, zirconium, thorium, tin, rhenium or a group VIII metal or a mixture of at least two of these salts in a corresponding amount 0.1 to

10% of the weight of the metal.

The invention also relates to a hydrogenation process.

tion of polyunsaturated organic compounds into the compounds

partially or completely saturated corresponding which

is to put hydrogen under a pressure between

  1.013 x 105 and 2.7 x 106 Pa in contact with an organic compound

polyunsaturated picnic at a temperature between 30 and 240 ° C. in the presence of a nickel-based catalyst fixed on a support as previously described. We choose the duration of the

  contact so that the product obtained has the required composition.

  The nickel catalyst of the invention is suitable

particularly as a catalyst for hydrogenation of acid

unsaturated fats and their glycerides into the compounds par-

  correspondingly or completely saturated. This process is practiced with a hydrogen pressure included

6

  between 1.013 x 10 and 2.7 x 10 Pa at a temperature of 80 to 240 ° C. The conversion time is also chosen so that a product with the required acid composition is obtained.

  bold. The amount of catalyst is approximately understood

required between 0.01 and 2% by weight of metallic nickel compared to

weight of the raw material used and it

is preferably between 0.02 and 0.06% by weight.

  The hydrogenation process can be practiced.

the invention continuously or discontinuously.

  The exposure of the precipitate obtained by mixing a solution

  tion of a nickel salt with an alkali to the action of a solution

tion of alkaline borohydride causes an exchange of part

  superficial hydroxy radicals of the dihydro structure

nickel xyde and / or basic nickel carbonate by a-

  nion (BH4) _. The finished catalyst has an activity and a selection

  hydrogenation activity of polyunsaturated organic compounds

in partially or completely saturated compounds

several times greater than that of a product

similar that was not treated with an alkaline borohydride.

  The catalyst of the invention is suitable for processes

such as the hydrogenation of cyclooctadiene to cyclooctene.

However from an industrial point of view, the hydrogenation of unsaturated fatty acids and their glycerides to the corresponding partially or completely saturated compounds is

  much more important. When operating selectively, -

to obtain partially hydrogenated vegetable oils, the hydrogenation is essentially stopped between 0 and 30% by

  weight of the initial amount of linolenic acid. For example-

  ple, when rapeseed oil having a minimum erucic acid content, the initial iodine index of which is 115 is treated, the hydrogenation is stopped when an iodine index of 90 to 100. In the conditions

  data, the ester content of linoleic acid is reduced

  te to 50 to 80% by weight of the initial content. The oils thus

  if processed are suitable for the subsequent production of various

  its sorts of oils for salads, of Moyonnaises, of margari-

nes, etc.

The selective properties of the catalyst also allow

to obtain a relatively high acid yield

oleic during the hydrogenation of vegetable oils. For example-

  ple in the treatment of rapeseed oil with a minimum erucic acid content, the maximum content of the oleic acid esters in the product is about 83% and the

  product thus obtained can be subjected to a further treatment

laughing in technical applications.

  The catalyst of the invention is also suitable for hy-

  drogenation of vegetable oils to obtain a product having a melting point of 32 to 390C which is subjected to a further treatment to produce margarine, fat for diabetics, etc. It is also useful for the total hydrogenation of vegetable oils or free fatty acids for

obtain products with an iodine value of 2 to 5, the activity

  high catalyst rate playing a major role in

such hydrogenation.

247295?

  The invention is illustrated by the non-limiting examples

following tifs.

EXAMPLE 1

  A suspension of diatomaceous earth is added with stirring

mées in a solution of nickel nitrate at 95 C in a

hot solution of sodium carbonate. To complete the pre-

cipitation a sodium hydroxide solution is added in

an amount such as the molar ratio of alkali to nic-

  kel is 2/1. After filtration, washing and drying, the pre-

cipity meets the NiCO3 formula. 10.5 Ni (OH) 2. 0.7 E20 and subjected to pH 10.5 to the action of a 10% aqueous solution

sodium borohydride (pH = 10) for 60 minutes. Then

we separate the precepitate by filtration, we wash it three

  times with methanol, calcine at 350 ° C. and finally reduce

between 360 and 380 C for 10 hours to obtain a degree of reduction of 0.86. The catalyst obtained contains

weight, 51.1% nickel and 0.8% boron, the remainder being

support.

  The catalyst thus prepared exhibits activity and

  a hydrogenation selectivity of cyclooctadiene in cyclo-

  -Octene in liquid phases significantly higher than those of a

catalyst prepared in a similar way but without the carbon

  basic nickel nate has been contacted with borohydride

sodium. Quantitative results including conditions

  The hydrogenation reaction is shown in Table I.

TABLE I

Comparison of the evolution of the hydrogenation of cycloocta-

diene in cyclooctene with a catalyst prepared as described in Example 1 (catalyst A) or a similar catalyst

prepared without treatment with sodium borohydride (cataly-

Sister B).

  Reaction conditions: temperature 30 C; hy- pressure

drogen: 1.0374 x 105 Pa; cons

catalyst concentration: 0.833 g Ni / l of reaction mixture;

solvent: normal heptane.

  TABLE next page D: cyclooctadiene M: cyclooctene S: cyclooctane

EXAMPLE 2

  As described in Example 1, a nickel nitrate solution containing 10% silver nitrate is treated. The catalyst obtained by reduction of the sample at 350 ° C. until a reduction degree of 0.8 is obtained contains, 8% by weight of nickel, 0.53% by weight of boron, and 0.5% by weight.

weight of silver, the rest being made up of the support. The cat-

lyser is three times more active and 2.8 times more selective in the hydrogenation of cyclododecatriene to cyclododecene than a similar sample which was not treated with

sodium borohydride.

EXAMPLE 3

  In a precipitating vessel, a suspension of diatomaceous earth is introduced into a solution of nickel chloride containing PdCl2 in an amount corresponding to 0.1% of palladium. After heating to 98 ° C., the carbonate is precipitated

  basic nickel by adding sodium carbonate

CATALYST A lf CATALYST B Time Concentration of the individual components (min) (mole / liter x 10- 2)

D M S D M S

0 5.44 0 0 5.38 0 0

3.38 1.96 0.04 4.56 0.77 0.05

1.84 3.38 0.11 3.90 1.31 0.18

0.32 4.56 0.50 2.84 1.97 0.55

0.03 4.36 1.02 2.10 2.23 1.01

0 3.88 1.54 1.59 2.28 1.48

0 3.40 2.02 1.18 2.21 1.98

0 2.58 2.86 0.67 1.85 2.84

0 1.92 3.50 0.36 1.44 3.54

0 1.42 4.04 0.21 1.10 4.06

0 1.02 4.44 0.13 0.78 4.48

0 0.72 4.72 0.06 0.56 4.75

  2.1 mole bran per mole of nickel. 0.01 mol% of sodium borohydride is then added to the suspension in the mother liquor and the mixture is stirred at pH 13.7 for 10 minutes at 980C. After filtration, washing, drying and calcination at 4000C, the catalyst is reduced to 4500C to obtain a degree of reduction of 0.85. The catalyst obtained contains by weight

  58.2% nickel, 0.85% boron and 0.1% palladium, the res-

  being made up of the support. Treatment with bborohy-

sodium dride increases the selectivity of hydrogenation of cyclooctadiene to cyclooctene of the catalyst by a factor of 3.1.

EXAMPLE 4

A nickel nitrate solution is precipitated at 300C

containing diatomaceous earth with a quantity of hydro-

sodium xyde equal to 1.5 moles per mole of nickel. We mix

  the suspension of nickel dihydroxide obtained with a solution of sodium borohydride (0.6 mole of borohydride

per mole of nickel) and heated to 70-80 ° C for 60 minutes

your. After filtration, washing, drying, calcination at 3000C

  and reduction to 350 C until a degree of reduction is obtained

  tion of 0.63, the catalyst obtained contains 28% by weight of nickel and 0.3% by weight of boron. The catalyst has a selectivity for hydrogenation of cyclooctadiene to cyclooctene, 3 times greater than that of a similar sample as 1 '

  it was not treated with alkaline borohydride.

EXAMPLE 5

  In a stainless steel autoclave fitted with a stirrer

  turbine turbine, 80 g of refined rapeseed oil having a reduced erucic acid content and a catalyst containing 3.8% by weight of boron and 27% by weight are introduced

of nickel, 48% of the nickel being in the form of metallic nickel

  than. The amount of catalyst is 0.04% by weight of nic-

  kel relative to the weight of the oil used. We hydro-

gene at 1800C under a hydrogen pressure of -1.52 x 105 Pa.

  Variations in the composition of the product during the hy-

  Drogenation are shown in Table II which clearly shows the high selectivity and the high activity of the catalyst. The quality of the product obtained allows its subsequent transformation into components of a salad oil, mayonnaise, margarine, fat for diabetics, etc.

TABLE II

  Hydrogenation of rapeseed oil having an erucic content reduced to the minimum under the conditions in Example 5.

EXAMPLE 6

With in acid indicated

  the same autoclave as in Example 5,

ne 80 g of sunflower oil having the following composition: The iodine index determined according to the Wijs method is 129. The catalyst is separated by filtration

  previous and recycled at 0.03% by weight of nic-

kel in relation to the weight of the oil. Hydrogenated at 140 ° C. under a hydrogen pressure of 1.52 × 10 Pa. After 160 minutes, Time Index Fatty acid content (% by weight) (min) of stearic oleic linoleic linoleic iodine

0 115 2.6 59.2 21.3 7.3

3,111 2.8 62.7 19.3 5.7

104 2.9 66.7 16.7 4.0

7 98 3,]. 70.2 14.8 2.3

9 95 3.3 73.5 12.9 0.9

12 89 3.5 76.8 9.8 0

85 3.7 80.7 5.7 0

17 79 5.5 83.0 3.0 0

76 9.7 82.0 0 0

24 70 15.2 77.1 0 0

63 21.0 71.7 0 0

36 59 26.7 66.2 0 0

55 32.2 60.7 0 0

  Acids% by weight Acids% by weight palmitic 6.73 arachidic 0.54 palmitoleic 0.14 eicosenoic 0.76 stearic 3.96 behenic 0.81 oleic 20.28 erucic 4.95 linoleic 61.83 the melting point of the product reaches 32.20C and the product has a consistency suitable for further processing

in margarine.

EXAMPLE 7

As described in Example 5, 80 g of hydrogen are hydrogenated.

  fats with an iodine value of 56 from the distill-

lation of animal fats. Hydrogenated at 200 ° C under a

2.344 x 106 Pa hydrogen pressure in the presence of a cat-

  lyser containing 0.25% by weight of boron and 45% by weight of

nickel, 87% of nickel being in the form of metallic nickel.

  The amount of catalyst is 0.43% by weight of nickel relative to the weight of the fatty acids used. After 90

minutes, an iodine value of 2.5 is reached.

Claims (10)

  1. Nickel-based catalyst fixed on a mineral support   ral such as diatomaceous earth, alumina or silica gel, characterized in that it consists of 10 to 85% by weight of nickel, of which 40 to 90% are in the form of nickel   metallic, and from 0.05 to 6.7% by weight of boron.   2. Nickel-based catalyst according to claim 1, characterized in that it contains 0 to 10% by weight of copper, silver, chromium, zirconium, thorium, tin, rhenium or one of the Group VIII metals, or a mixture at least two of these metals. 3. Method for preparing a nickel-based catalyst according to claim 1, characterized in that it consists in: (1) precipitating a suspension of an inorganic support in a solution of a nickel salt, with an alkali, (2) subjecting the mixture of the mineral support and the precipitate of nickel dihydroxide and / or basic nickel carbonate having the composition NiCO 3.x Ni (OH) 2.y H2O, ox is a number from 1 to 30 inclusive and there is a number   any action of a solution of borohydride al- hug at a rate of 0.005 to 1.25 mole of borohydride per mole of nickel, at a temperature between 20 and 'C and at a pH greater than 10 for a period of 5 to minutes, (3) wash and dry the mass obtained , (4) calcine at a temperature between 300 and 500 ° C., and   (5) reduce to a temperature of 250 to 4800C until obtaining   tion of a degree of reduction between 0.40 and 0.99.   4. Method for preparing a nickel-based catalyst according to claim 2, characterized in that it consists in (1) precipitating a suspension of an inorganic support in a suspension of a nickel salt, with an alkali, ( 2) subject the mixture of the mineral support, the precipitate of   nickel dihydroxide and / or basic carbonate of nic-   kel having the composition NiCO3.x Ni (OH) 2.y H2O, ox is a number from 1 to 30 inclusive and y is any number, and of a salt of copper, silver, chromium, zirconium, thorium, tin, rhenium, a group VIII metal il or a mixture of at least 2 of these salts   in an amount corresponding to 0.1 to 10% by weight of metal tal, to the action of an alkali borohydride solution in an amount of 0.005 to 1.25 mole of borohydride per mole of nickel, at a temperature between 20 and 100 ° C and at a pH greater than 10 for a period of 5 to 60 minutes, (3) wash and dry the mass obtained, (4) calcine at a temperature between 300 and 5000C, and   (5) reduce to a temperature between 250 to 4800C up to   that obtaining a degree of reduction between 0.40 and 0.99.   5. Nickel-based catalyst characterized in that prepared it according to the method of one of claims 3 or 4. 6. Process for the hydrogenation of poly- organic compounds   unsaturated to the partially or completely saturated compounds   corresponding turbines, in the liquid phase, characterized in that it consists in putting hydrogen under a pressure of 1.013 x 105 to 2.7 x 106 Pa in contact with an organic compound   that polyunsaturated at a temperature between 30 and 2400C in the presence of a nickel-based catalyst according to one which   conch of claims 1, 2 or 5 for a period such   that a product having the required composition is obtained.   7. Process for the hydrogenation of unsaturated fatty acids and / or their glycerides, in compounds partially or com- fully saturate corresponding, in liquid phase, characteristic se in that it involves putting hydrogen under a pressure   sion of 1.013 x 10 to 2.7 x 10 Pa in contact with an unsaturated fatty acid or a mixture of unsaturated fatty acids and / or their glycerides at a temperature between 80 and 240 ° C in the presence of a nickel-based catalyst according to one which conch of claims 1, 2 or 5 for a period such   that a product having the required composition is obtained.   8. Method according to claim 7, characterized in that the amount of catalyst is between 0.01 and 2%   by weight of metallic nickel relative to the weight of the ma- first implementation.   9. Method according to claim 8, characterized in that the amount of catalyst is between 0.02 and 0.06% by weight of metallic nickel relative to the weight of the raw material used.   10. Partially or completely saturated organic compounds characterized in that they have been prepared according to the   the method of any of claims 6 to 9. s