DE1545249C - Process for increasing the UV stability of paraffins - Google Patents

Description

1 2

The invention relates to the hydrogenation of paraffin or cobalt

finen, especially of paraffins, which are from petroleum 1 to 15 percent by weight, calculated as NiO or

can be obtained. CoO,

With the term "paraffin" used here

Both paraffin 5 iron obtained from petroleum distillates

fine (crystalline paraffins) as well as from residues 3 to 25 percent by weight, calculated as Fe ₂ O ₃ ,

obtained paraffins (microcrystalline paraffins) platinum group metals

draws. These paraffins are usually identified with “. ,. , _,. ,. . ■, '\,

Sulfuric acid and / or fuller's earth treated. The: ⁰ A to 5 percent by weight, calculated as metal,

Acid treatment is used to remove unstable components, io rhenium '

'For the bad smell of the wax and its _{x 2 to} 5 weight percent, calculated as Re ₂ O. ₇ poor color stability are responsible, dated

To remove paraffin, and the bleaching earth treatment. Preferred hydrogenation components are used to neutralize and decolorize the paraffin. Group VI metal oxide or sulfide together Another common method of refining 15 with one or more oxides or sulfides of paraffins is percolation over a solid adsorbent iron group metal. Particularly preferred as a hytion agent, such as bauxite. Third components become 3 to 20 percent by weight. These treatments give paraffins of molybdenum oxide and 1 to 10 percent by weight of nickel of acceptable quality, but they have oxide or nickel and cobalt oxide. For example, the disadvantage that the product yield is reduced, the catalyst may contain 9 to 15 percent by weight of MoO ₃ and large amounts of the consumed acid and 3 to 5 percent by weight of NiO. When fuller's earth must be eliminated. For this two-step process, the refineries now prefer to use a mild hydrogenation metal for each catalyst for the same reasons,
hydrocatalytic process, which is generally known as any activated carbons, hydrofinish treatment is known and in which those activated carbons are preferred which have the unstable components of paraffin with a surface area of at least 1000 m ² / g. An activated carbon is particularly suitable for elevated temperatures and increased pressure, which is made from pine wood from hydrogen and a hydrogenation catalyst and has the following properties:

be selectively converted by the hydro surface,. 1200m ² / g

finish treatment are products of good quality 30 _pv .. _ηήη ,,

odor and good odor stability, but not "ο ° u? _tt " · 'ί, ί'"""η« ι 3

a!. = Hydi.finish.Procedure ;; “Give products that %% £ * £ * \ \ \ \ \ \ \ 'S sfi diameter

are color-stable if they conform to ultraviolet light or ⁵

direct sunlight (the ultraviolet light is released as a fireproof inorganic oxide that holds as a carrier) get abandoned. So z. B. after the substance is used, this is preferably used hydrocatalytic process of the British patent oxide of an element of groups II to V of the Periscript 851969 paraffins received that already have an odic system, z. B. silica or preferred certain Have color stability, against prolonged UV as aluminum oxide. The alumina will Radiation are still insufficiently color stable. prior to the addition of the hydrogenation components

It has now been found that paraffins of increased 40 wise at a temperature of 500 to 900 ⁰ C, in particular

Resistance to ultraviolet light obtained special calcined at 700 to 900 ° C.

can be, if the carrier of the hydrogenation catalyst The following process conditions are preferred

sators is chosen correctly. It has been shown that:

particularly good results are obtained when the temperature 300 to 35O ⁰ C.

two catalysts with different types of supports. 45 Amount of hydrogen 'for the ""' "

can be used sequentially. Treatment 20 to 80 V / V

The method according to the invention for increasing pressure from 40 to 106 kg / cm ²

the UV stability of paraffins is characterized by this.

zachnet that the paraffin is mixed with _{kdt des Eins} ^B _a f _zes * _{Ql up to} 4 _{V / V / hour}

at least 20 spaces of hydrogen per .1 space- 5 ° ■. '.''
part paraffin at temperatures between 250 and, the feedstock is preferably in 360 ° C and increased pressure first over a catalyst the liquid phase and flows from top to bottom sator, which consists of one or more hydrogenation via the catalyst, which the Has the form of a fixed metal bed on a refractory inorganic oxide. In each stage of the two-stage process, sluggish passes are passed, and then, via a second 55, preferably the same working conditions are applied to the catalyst, which is turned from one or more. .
There is hydrogenation metals on an activated carbon support. It is not essential that pure hydrogen

The hydrogenation metals used are preferably those. A hydrogen-rich one is suitable of Group VI or VIII of the Periodic Table Gas, which is a by-product of the catalytic reforming or rhenium is used. The metals, in particular 60> mation, accumulates. When using unclean the metals of group VI, the iron group metals hydrogen, it concerns with the above mentioned or rhenium can in the form of their oxides or named preferred pressures around · the hydrogen sulfides be used. The amounts of each metal partial pressures.

can lie within the following ranges: Crystalline paraffins are used as input materials

65 preferred, which preferably has an oil content of

Group VI metals have less than 1.5 weight percent.

3 to 25 percent by weight, reckoned as the oxide It is important to the procedure mentioned in that

MoO ₃ , Cr ₂ O ₃ or WO ₃ , sequence to carry out, ie the treatment

first with the catalyst, which contains the refractory oxide as a carrier, and then with the catalyst, contains activated carbon as a carrier. If the order is reversed, there will be gets worse results. It is also necessary that the hydrogenation component be on the activated carbon is located, d. In other words, the process does not only involve the adsorption of color-unstable substances by the activated carbon, but also the conversion of these color-unstable substances by the hydrogenation component.

The product not only has increased color fastness to ultraviolet light, but also acceptable properties in other respects, e.g. B. color, odor stability, penetration, melting point and suitability for chlorination. Improved color fastness to ultraviolet light in the frame in this specification preferably means that a paraffin product with an initial color of At least +25 Saybolt has a color greater than +20 after 20 hours of exposure to ultraviolet light retains. Exposure to ultraviolet light is done by placing glass bottles containing the paraffin should be placed in a round chamber with an ultraviolet lamp of 125 W in the center is arranged. The bottles are placed at a distance of 22 cm from the lamp and after Rotated 180 ° for 10 hours.

The catalyst containing the activated carbon as a support can optionally be regenerated by Water vapor is blown through at a temperature not exceeding 260 ° C. A similar maximum Temperature can also be used for the preparation of the activated carbon catalyst, which otherwise takes place according to standard methods be applied. For example, a catalyst that can contain Ni, Co and Mo on activated carbon contains, be prepared as follows:

a) The activated charcoal is dried at 110 ° C. for 12 hours and then impregnated with a solution of ammonium molybdate. The catalyst will Left to stand for 6 hours at room temperature and then dried at 110 ° C. for 12 hours.

b) The catalyst is simultaneously impregnated with solutions of cobalt and nickel nitrate. He is 6 hours at room temperature. left to stand and then ge for 12 hours at 110 ° C. dries.

c) The catalyst obtained is then heated for 4 hours.

A maximum temperature of 260 ° C. is useful if the catalyst is heated in air is, however, higher temperatures up to 350 ° C can be used if the catalyst in an inert gas, e.g. B. nitrogen is heated.

In the process according to the invention, the regeneration of the catalyst, which is the refractory Contains oxide as a carrier, take place in the normal way (regulated burning of the deposit in one Mixture of oxygen and inert gas or oxygen and water vapor at a temperature that is preferred maximum 400 ° C). The preparation of this catalyst can also be carried out according to the usual Practice. .

The two catalysts of the process can be in the same reactor or in separate reactors be included. The latter case is preferred because of the different regeneration conditions required.

In the process according to the invention, the paraffin in liquid form is preferred before hydrogenation subjected to a treatment by which it deflates and of traces of entrained Solvent is freed, which could cause deterioration of the paraffin. A suitable one. The form of pretreatment is, for example, a steam treatment, which is preferably carried out at temperatures carried out in the range from 80 to 100 ° C

Will. ■■ · - - - ■■ ': ■ ■■■ "----- Ar ' · '■: - - \ - ^ -

The paraffin is then mixed with the necessary amount of hydrogen. The mixture is on heated to the desired reaction temperature and then at the desired flow rate and passed over the catalysts at the desired pressure. -

First, the gas is released from the product at the reaction pressure severed. The remaining gas is then separated off in a second low-pressure separator. Finally, the paraffin is rectified in steam and then dried in a vacuum.

The comparative tests described in Examples 1 and 2 represent the state of the art.

For example

A crystalline paraffin which had a melting point of 51 ° C was made under the following conditions treated: ·

Temperature 340 ° C

Hydrogen pressure 50 kg / cm ²

Amount used .... 0.5 V / V / hour

Amount of hydrogen: 40 V / V

A catalyst consisting of nickel oxide on activated carbon and a catalyst consisting of nickel oxide insisted on alumina were used.

In both cases the catalyst had the following composition:

Nickel oxide (NiO) ... '. 15 weight percent carrier 85 weight percent

The following results were obtained:

NiCVAl ₂ O ₃ catalyst

Saybolt color after the

treatment

After 1 hour heating to 200 ° C

After 20 hours of exposure
of ultraviolet light

. +25 + 15

+ 6

NiO / active

coal catalyst

+25 +23

+22.

Example 1-2,

The same crystalline paraffin was treated under the conditions mentioned in Example 1, wherein a catalyst made from the oxides of molybdenum, cobalt and. Nickel insisted on activated carbon, and for comparison, a catalyst consisting of the oxides of molybdenum, cobalt and nickel on aluminum oxide was used. In both cases the catalyst had the following composition:

Molybdenum oxide MoO ₃ 15 percent by weight

Nickel oxide NiO ..... 1 percent by weight

Cobalt oxide CoO 4 percent by weight

Carrier 80 percent by weight

The following results were obtained:

Mo-Co-Ni /
Al ₂ O ₃ -
catalyst Mo-Co-Ni /
active
money-
catalyst Saybolt color after the
treatment
After 1 hour heating up
200 ⁰ C ... ' +25.
+20
+20 +25
+23
+24 After 20 hours of exposure
of ultraviolet light

Example 3

A crystalline paraffin with a melting point of 50 to 52 ° C was treated under the following conditions:

Temperature 340 ⁰ C

Pressure . ■}: ■ 50 kg / cm ²

Input amount; , 0.5 V / V / hour

Amount of hydrogen 40 V / V

Two catalysts were used separately and in combination. The composition of the catalysts and the results obtained are given in the following table:

Hydrogenation at 340 ° C

Hydrogen pressure 50 kg / cm ²

Specific room air velocity 0.5 V / V / hour.

Amount of hydrogen supplied 40 V / V

Acid and
Fuller's earth
treatment Catalyst 1
alone
MoO ₃ 15%
NiO 5%
on aluminum
oxide Catalyst 2
alone
MoO ₃ 15%
NiO 1%
CoO 4%
on activated carbon Catalyst 2,
then
Catalyst 1 Catalyst 1,
then
Catalyst 2 Saybolt color after treatment ...
After 1 hour of heating to 200 ^° C. ...
After 20 hours of exposure to Ultra
violet light +25
+24
+ 24
+23 +25
+22
+ 8
strongly colored +25
+23
+24
+ 10 +25
+ 18
+ 15
strongly colored + 25
+24
+ 24
+23 After 8 days of exposure to the sun
light

Example 4

Two different crystalline paraffins with a melting point of 50 to 52 ° C or 60 to 62 ° C were treated in a two-step process with a Ni-Mo catalyst in each reactor has been used. The catalysts had the following composition:

The following results were obtained:

45

First reactor

MoO ₃ 15 percent by weight

NiO 5 percent by weight

Aluminum oxide ..... 80 percent by weight

Second reactor

MoO ₃ 15 percent by weight

NiO 5 percent by weight

Activated charcoal 80 percent by weight

paraffin
from the
Enamel
point 50
.to 52 ° C paraffin
from the
Enamel
point 60
up to 62 ° C Saybolt paint before aging
Saybolt color after an hour
Aging at 20O ⁰ C
Saybolt color after 20 hours
Exposure to ultraviolet
light; .. + 25
+ 23
+ 22
+22 +25
+25
+23
+24 Saybolt color after 8 days on
effect of sunlight

55

The following hydrofinish conditions were used in each reactor:

Temperature 340 ⁰ C

Hydrogen pressure 50 atmospheres

Flow rate of the insert .. 0.5 V / V catalyst / hour. Hydrogen quantity 40 V / V input

Claims (1)

Claim: A method of increasing the UV stability of paraffins, characterized in that first passes the paraffin in admixture with at least 20 parts by volume of hydrogen to 1 part paraffin at temperatures between 250 and 36O ⁰ C and elevated pressure over a catalyst of the plurality of one or There is hydrogenation metals on a refractory inorganic oxide carrier, and then passes over a second catalyst, which consists of one or more hydrogenation metals on an activated carbon carrier.