DE1071084B - Process for the homogeneous, non-catalytic partial oxidation of oxidizable organic compounds - Google Patents

Description

GERMAN

kl 12 ο

INTERNAT. KL. C 07 b

PATENT OFFICE

St 7363 IVb / 12 ο

4NMEIDETAGi NOVEMBER 24, 1953

NOTICE THE REGISTRATION AND ISSUE OF THE EDITORIAL: DECEMBER 17, 1959

The invention relates to a method for the homogeneous, non-catalytic partial oxidation of oxidizable organic ones Compounds in the vapor state.

It is known that the selective, non-catalytic oxidation of paraffinic hydrocarbons in the vapor state 5, a substantially homogeneous chain reaction, which starts at Temperattiren between 260 and 32O ⁰ C. After the reaction begins spontaneously, the oxidation proceeds extremely rapidly, with the phenomenon called "cold flame" appearing. As a result of the extremely high rate of oxidation, the reaction is limited to a very small part of the reaction chamber; it is normally characterized by a sharp rise in temperature of about 150 to 200 ° C in this reaction zone. The increased temperature undesirably worsens the selectivity of the reaction and can lead to the complete conversion of the feed to water and carbon

oxides lead.

This undesirable influence of the higher temperature ao

or the lack of means to regulate the temperature

can be seen from the data recorded in Table 1. 2

Tabel

Effect of temperature on the non-catalytic oxidation carried out in the vapor state of hydrocarbons in an empty steel reaction vessel

Process for homogeneous,

non-catalytic partial oxidation of oxidizable organic

links

Applicant:

Esso Research and Engineering Company, Elizabeth, N.J. (V.St.A.)

Representative: Dr. W. Beil and A. Hoeppener, lawyers, Frankfurt / M.-Höchst, Antoniterstr.

Claimed priority: V. St. v. America February 27, 1953

Oxidized hydrocarbon

n-heptane

Light, untreated

Oil from East Texas (boiling range = 65 to 115 ⁰ C)

Composition of the vapor charge:

Hydrocarbon, percent by volume

Oxygen, percent by volume

Steam or nitrogen, percent by volume

Contact time, seconds

Oxygen / hydrocarbon molar ratio

Reaction ^{temperature, 0} C (average)

Hydrocarbon converted,% / ₀

Reacted oxygen, ° / o

Analytical data of the hydrocarbon layer:

Carbonyl: le oxygen per 100 g hydrocarbon layer)

Bromine number

Volume percent in 98 ° / ₀ hydrochloric H ₈ SO ₄ Dissolved

Selectivity in% for

non-condensable gases

liquid olefins

Epoxies

Carbonyls

5.4
4.8
89.8
3
0.89

60 400 450 30th
72 29
73 16
53 0.8
10.7
20th 0.7
13.0
19th 0.3
10.5
9 17.7
10.8
36.8
19.6 18.2
16.8
35.3
15.2 30.2
22.4
26.1
12.0

380

35
94

0.7
17.1
18th

25th
25th
25th
15th

415

30th

95

0.5
12.3
16

17.4 14.8 67.8 10 0.85 430

15 97

0.2

4.2 5.5

450

15 97

0.3 4.4

3 4

The results in Table 1 were used in experiments. B. in the presence of a noteworthy large found, which with an excess of a dilution-fixed inert surface no oxy agent at all, such as steam, for the most precise control of the dation at temperatures up to 500 ° C instead.
Reaction temperature had been carried out. Finally, it was also suggested that the hydrocarbons given in the table should be oxidized in the presence of various catalyst feeds decreased when the reaction temperature was increased; , but stuff. In the case of n-heptane feeds, the predominantly heterogeneous reaction in one for the consumption of oxygen also decreased with increasing temperature. Catalyst used characteristic direction The overall decrease in reactivity was influenced by io. As a result of the relatively short life, accompanied by a decrease in the selective yield of valuable duration and high costs of the catalysts and the oxygen-containing compounds, as well as by the relatively small number of undesirable non-condensing reactions that occur in practice, the use of such catalytic gas mixtures rich in carbon dioxide became possible . Process mainly focused on the production of high quality

The amount of temperature rise can be limited to either 15 chemicals such as phthalic anhydride; thereby adjusting the feed rate or against it proving to be somewhat uneconomical to improve the octane number of the oxygen-hydrocarbon ratio by petroleum and other important uses, or by using an inert one with low profit margins.
In the partial oxidation process according to the present substance at numerous successive points, the invention is avoided in order to prevent excessive temperatures in the reaction zone. None of these means bring about temperature rises in such a way that a flow of vapors of organic compounds can be achieved in a reaction vessel when working in an open tube, since in such a system the temperature alternates from bottom to top through many with regulation The end, always filled by the relatively inert, finely divided, whirled-up solids, weak transfer of the heat of reaction from the gas spaces and many of these inert solids conducts almost shaped reaction participants to the walls of the reaction-free spaces (e.g. gas pockets, gas bubbles) , whereby the tion vessel is restricted. In addition, the solids-poor spaces (gas bubbles, pockets), in which the use of a diluent is often seen as undesirable, the conversion of the gaseous starting materials, because it is the extraction of the finished, are several times larger than the rooms in comparison to those processes in which there are 33 solid particles between adjacent solid particles in the spaces containing essentially pure oxygen as the oxidizing agent, making it difficult to use the stream of vapor or an oxygen-rich gas. Fönnigen organic compounds in the almost solids-Furthermore, even in the presence of 60 to 90 volume-free spaces at reaction temperatures between 275 percent diluent, as much heat of reaction and 480 ° C up to a period of 10 seconds is generated that in an open reaction vessel the tem- 35 a free oxygen-containing gas selectively oxyperaturen by about 30 to 12O ⁰ C or more above the diert and can thereby be the local molar ratio of free desired value. The above-mentioned oxygen to the organic starting compound showed the disadvantageous effect of excessively high temperatures at most 1.25, which proves that the vapors obtained by the selective doors and the inadequacy of conventional means for re-oxidation to dissipate the excess of the reaction temperature are proof Clearly, 40 Schüssigen Oxydarionswärmc in the inert solids that it is important either to introduce the temperature inside the fluidized bed, to distribute the inert solids evenly half of the reaction zone or that cools the fluidized bed, the oxidation products above reaction heat from the gas phase quickly and effectively withdraws from the reaction vessel and to derive it in itself. known way worked up.

In order to achieve a sufficiently high conversion 45 it is already known that in the vapor state

of the hydrocarbon in each process, it is fende chemical reactions to regulate the temperature

desired to carry out oxygen in a ratio of at least in such a way that one finely divided,

Apply 0.3 to 0.5 moles per mole of hydrocarbon. catalytically inactive solid in the reaction

These relatively high amounts of oxygen lead to the zone in a fluidized bed, and keeps the

but easy to heat the reaction zone to 50 reaction products free of solid constituents therefrom

the pyrolysis temperature of the hydrocarbon, so that withdraws. The main purpose here is the fluidized bed

to avoid excessive quantities of the load, good heat absorption and heat distribution

niger valuable gaseous paraffins, olefins and allow, however, have become known

Carbon can be decomposed. As a result, the procedure was nowhere from gas bubbles or gas pockets

Lack of proper temperature control of any of the 55 uniform, practically free of solids

main barriers to industrial recovery gas phase in contact with the fluidized bed in the

the non-catalytic selective oxidation. Reaction zone present, and also that

Accordingly, various means have already been known both with inert and with

proposed that the reaction vessel be carried out by immersion in catalytically active solid particles,

a suitable heat exchange medium to cool. This 60 while in the present case the solid particles always

however, they only had to be somewhat inert in the case of smaller systems.

measured successfully and proved to be neither by this known method of operation nor by using reaction vessels with larger diameters being quite ineffective. However, it is known to other prior publications Attempts have been made to achieve partial oxidation by creating a stream of the organic reaction rules that roan the reaction participants via cooling participants !! alternately by a large number of snakes or other inert surfaces, such as dense layers, partly containing solids, partly solids-free spaces granular solids, headed. This attempt proved, preferably in the form of gas bubbles, to let migrate however, it also proves to be fruitless, as inert surfaces, such as The way in which this method is practical found to be excessive in response is best understood from the description have an inhibiting or harmful effect. So 7 ° found the drawing understandable.

In the drawing shows

Fig. 1 is a side view of a reaction vessel more suitable Type with accessories,

2 shows a vertical section of an even more elaborate reaction vessel in which the reaction zone contains a grid-like, cell-shaped installation,

Fig. 3 shows the front view of a further reaction vessel several intermediate floor, which is particularly advantageous for carrying out selective oxidations of Hydrocarbons proved

FIG. 4 shows a cross section through the reaction vessel containing several trays along line IV-IV of FIG Fig. 3.

It has been found that the oxidation can be carried out in a layer of inert solids, e.g. B. glass beads or Sand, can control or inhibit, considering such factors as size of solid particles, surface velocity or flow rate of the steam and nature of the reaction vessel, accordingly adjusts. So one investigated z. B. in a reaction vessel, which only consists of an approximately 46 cm long inside an annular space formed of a tube of 8 cm inside diameter and with a stirrer 5 cm in diameter, the effect of various solids on oxidation different hydrocarbons at different temperatures. The hydrocarbon to be oxidized was through a sintered plate located at the lower end of the tube into the lower part of the reaction vessel initiated, during the well-agitated solids layer at one, about 5 cm above the hydrocarbon inlet pure oxygen was added to the lying position. The mixture of hydrocarbons and oxygen then slowly rose through the stirred bed of solids. Furthermore, the upper part of the Solid layer are cooled from the outside by water or air nozzles, whereby it was prevented that any reactions between the hydrocarbon in the empty space above the solid layer and the oxygen took place. The results are shown in Table 2. In addition, the pre

ao direction in numerous places with means for removal of steam samples provided during the procedure.

Table 2
Oxidation of n-heptane in the vapor state in a stirred solid layer

Solids Molar ratio Jieriih- Maximum Steam- . Composition of CO CO ₂ unge Liquid
Volunteer Products Ver Oxygen too
Coals ration time
in tempe
rature in flow- non-condensable gases satiated percent search
"NJV hydrogen Seconds ⁰ C speed
age 25.5 9.7 Connect au in
H ₈ SO ₁ bromine ΧΝΓ. Liter/ 1.7 1.3 fertilize soluble number no O ₂ - 12th 37.7 Fluid Glass beads 0.25 3 400 j V UII Ut! H 6.0 18.7 0.7 opportunities 1 of 300 μ 0.25 3 325 2.7 9.7 26.0 - 13th 12.7 2 diameter 0.25 3 410 170 86.8 23.7 20.0 4.7 1 0.1 3 0.25 3 450 170 75 36.0 22.0 15.8 3 - 4th Glass beads from 0.25 3 500 170 64.7 13.7 2 2.8 5 100 μ dia 0.25 6th 320 170 40.7 21.3 6th 6.2 6th knife 0.75 6th 370 <85 25th 11 7th <85 0.7 22nd -

As the results in Table 2 show, normal oxidation underwent in the empty reaction vessel Development of a maximum temperature of 400 ° C. The normal course of oxidation is due to the low Oxygen content of the reaction gas and the solubility of the liquid product in sulfuric acid are shown. In Presence of glass beads with a size of 300 μ and at a flow rate of about 1701 per hour the oxidation was only slight even at temperatures of 450 ° C. If, however, as in experiments 6 and 7, If significantly smaller glass beads were used, the reaction took place at a moderate temperature.

In the case of a reaction vessel that differed from the one described above only in that the outer one Metal tube was replaced by a piece of heat-resistant glass tube, it was observed that during construction the layer of relatively large particles, e.g. B. of 300 μ diameter or larger, which is in the layer inflowing vapors were easily dispersed even at flow rates of 600 liters per hour. On the other hand, gases weren't dispersed even at speeds as low as 60 liters per hour, if particles with a diameter of 100 to 150 μ are used but they rose in bubbles through the solid layer, like air bubbles through water. As the Results in Table 2 show the experiments were carried out using small glass particles with a flow rate of over 85 liters per hour, which is over that required for a dispersion Minimum speed. In the experiments with larger particles, the flow rate was about 600 liters per hour, so it was below that for the formation of bubbles speed required in the shift. The reason for having a reaction in the made smaller Particles existing layer occurs, lies in the fact that bubbles form at the flow rates used formed in the layer and the reaction took place in the bubbles or pockets of vapor. In the layer from the There was no reaction to larger beads, and there were no gas pockets at the flow rates used or bubbles formed because they were broken or dispersed. It was also found that one in the presence of such layers of small particles and under conditions in which bubbles form, can blow relatively large amounts of oxygen at any point in the layer without locally high temperatures occur, as the temperatures rise due to the whirling up of the suspended solids equalize everywhere. In addition, one can easily remove the heat of reaction from such a layer,

7 8

by immersing cooling coils in the layer or a fluidized bed consists of solids

the solids through an external cooling device essentially conducts from a number of small zones or cells

or uses other types of external cooling. to carry out the reaction in the gas phase, the

It has thus been shown that layers of inert solids increase due to the exothermic nature of the reaction

substances a good regulation of the desired oxidation temperature 5 are maintained, these zones with

enable reaction. When using small particles, moderately warm parts of the dense fluidized bed in

z. B. those up to 300 μ in diameter, and in particular touch or are enclosed in them,

those between about 40 and 220 μ in diameter or at their temperature through indirect heat exchange

the fluidization of particles of any particle size, inside or outside the main reaction vessel

with the formation of bubbles, the reaction takes place directly in the io can be regulated. In contrast to the main

Particle layer in vapor pockets or bubbles instead. neuter benefits that fluidized beds normally have

On the other hand, the solids prevent oxidation.

if one considers particles of a size of 300 μ or more lying in their non-uniformity, i. H. to the

used or works at flow rates, presence of small, hot gas cells of each

which are so low that within the layer there is no changing composition within the densities

Steam bubbles form and the solids form like a fluidized bed with their more moderate temperatures,

dense layer behave. As a result, such high temperatures can occur inside the small gas cells

Solid layers as non-reactive cooling layers and allow the oxidizing chain to spread

Mixing or gasification zones can be used, with reaction, while the surrounding inert dense solids

the reaction takes place when the reactants ao phase due to their inhibitory chemical action and

leave the shift. their slightly lower temperature than an effective one

The experiments described above were performed with n-heptane quenchants. On the other hand, you do that

executed; other hydrocarbons or petroleum and the entire fluidized bed are homogeneous and destroy the bubbles

whose fractions, apart from the aromatic compounds, always immediately after their formation, it becomes such

the fluidized bed essentially under the conditions described for the purposes of the present invention

are not oxidized, but behave similarly. So useless. In such a case there are no gas phases

z. B. cyclohexane, octene-2, light and heavy more available in which the reaction can take place,

Petroleum in the presence of small inert pearls under agitation while the large surface of the whirled up inert

conditions in which gas bubbles or solids in the homogeneous, bubble-free, dense solid

- forming pockets; However, they will not inhibit the oxidation in the same way as one in the presence of a material phase

a dense layer under conditions in which static embankment,

do not form vapor bubbles, oxidized. For the production of a fluidized bed according to the invention

The result is that dense layers of inert are of a suitable degree of fluidization or bubble content granular solids the selective oxidation of carbons - it is necessary to hydrate the inert solids harmful influence in the vapor state, 35 eddies that the reaction gases with a linear while whirled up inert. Solids as a surprising superficial gas velocity of about 9 to 150 cm effective means of influencing the temperature without per second, e.g. 15 to 45 cm per second, upwards undesirable retardation of oxidation act when the solid particles conduct; d. that is, used to generate spaces form in them, the gas velocity required for relatively free gas bubbles is greater of solids are. In particular, it was found that 40 was used to lift the weight of the embankment whirled up solids as a result of the relatively necessary. A high ratio of the total height to the large amount of steam-filled bubbles, pockets or diameters of the dense embankment turns out to be Cavities in such fluidized beds are also considered to be useful for carrying out the above Means for regulating the temperature in the case of the process, because reaction vessels that are so konder substantially homogeneous, in the vapor phase 45 are structured that they allow the use of such high carried out non-catalytic oxidation λ-οη nor- ratios allow the emergence of proportionally liquid paraffins such as petroleum fractions have a moderate amount of bubble space within the dense phase to serve. Favor embankment. As a result, the

Such bubbles or areas of low density differ from the height to the diameter of the reaction vessel

In this respect, at least 2: 1, but also 5: 1 to 10: 1, differ from the usual bubbles in 50

a liquid than they are not the same gas or more.

remains unchanged in the bubbles of a fluidized bed. When a bubble is on-Im through a dense fluidized bed On the contrary, in such a system flows constantly increasing, it decreases as a result of the gradual decrease fresh gas enters the lower part of the bladder and leaves pressure in size. Is the fluidized bed high enough this above again, which causes the gas composition 55 so the growth of the bladder can proceed so far, inside the bubble continuously changes, while that the bubble changes the size of the diameter of the reaction bubble even at a fairly high rate, the vessel reaches, whereupon one of solids more or more z. B. 30 cm per second or more, through the layer less free gas space from the width of the reaction upwards increases. It is clear that it is precisely such a vessel that forms a lump of tightly swirled solid parts the preheating of the feed gases in the 60 chen moves forward until the gases gradually dissolve Solid phase made possible without reaction, whereupon even by the dense aggregation of the solids the oxidation takes place when the mixture of coals work upwards. Such agglomerations Hydrogen and oxygen in one of the solids come in proportionately, especially in vessels relatively free bladder occurs. However, as soon as the small diameter is in front, the more common the larger the resulting hot reaction gases are through the upper 65 solid particles. For example, when particles occur Part of the bubble flow and back into the actual density with diameters between 200 and 300 μ Phase of the whirled up solids enter, clusters in vessels with 45 or even 60 cm penetration you through the large expansion of the inert knife; in the case of very fine particles, on the other hand, with Surface quenched quickly, d. i.e., the reaction will be about 40 to 100 microns in diameter Brought to a standstill. 70 agglomerations only in relatively narrow areas

9 10

Reaction vessels with. about 5 to 10 cm in diameter contact with burning or other hot gases

before. heated and then introduced into the reaction vessel,

Another method can be put together until it has the required temperature. Is this achieved clumps or bubbles arise in a fluidized bed, and once the exothermic oxidation has begun, it becomes if the reaction vessel is usually stopped at regular intervals of any external heating; it However, other longitudinally a number of wire screens may be advisable to place the preheater 12 on the or plates or other similar separating devices of the same type as described above begins. Will now use steam upwards through the normally liquid hydrocarbon reaction vessel headed, so occur in the immediate vicinity materials such. B. petroleum, above their point of condensation bubbles or clumps on the sieves. i ° to keep.

With reference to FIG. 1, the invention is oxy After the start of the reaction, excess dation can be explained with reference to an advantageous embodiment of heat either by the internal heat exchanger 5. In this device, a feed or devices such as external cooling jackets of vaporized hydrocarbon can be discharged through line 1, the reaction zone. Preferably, the distribution cone 2 and a grid or a sink 15 directs the solids to a special vessel, where the tertiary plate 3 is fed into the reaction chamber 10. it is blown with a cool gas or oxygen is also introduced into the chamber 10 via cooling surfaces. It conducts and then after cooling back into the oxidation can be advantageous to return the oxygen in a mixture with the reaction vessel. In the case of devices with two reaction vessels containing the hydrocarbon in a conventional preheater 12, it may be appropriate to preheat the same. Instead, you can blow the entire 2 ° vessel during the start-up period as a burner or at least part of the oxygen with one or for heating the circulating solids and during several oxygen lines 11 directly into the vortex of the progress of the process as a cooler for removal layer. When preheating the supply of excess heat to be used,
It is important to avoid temperatures that are sufficient to pass the mixture of hydrocarbons and oxygen of the gases into the fluidized bed when the oxidation reaction is initiated in the device shown in FIG. If a coal through the dense fluidized bed in reaction vessel 10, hydrogen-oxygen mixture in the reaction vessel, practically all of the oxygen is consumed rapidly during the introduction, it is advisable to set the preheating temperature to whirl up the solids uniform temperature of such a charge at least about 50 ° C without distribution to keep excessive local overheating below the start-up temperature. 3 ° each. As already mentioned, however, depending on the type of hydrocarbon temperature used in each case within the gas bubbles occurring, the vonvännt temperature is usually higher than in the surrounding dense phase. It is understood to be between about 150 and 250 ° C. If, however, it is found that the particular reaction temperatures mentioned in the present description and the particular reaction temperatures are introduced into the fluidized bed on the separate streams, either the average or the total temperature of the fluidized bed can either be one or both streams essentially. layer and not necessarily refer to the Tempalichen a \ if the reaction initiation temperature preheated temperature at which the reaction is actually within. The reaction gel aß 10 also contains finely divided inert solids of the individual gas bubbles contained in the layer, e.g. B. sand through which it pulls.

Reaction gases with a linear surface velocity 40 In the case of a reaction vessel in which bubbles or feed

speed of about 15 to 45 cm per second upwards, agglomerations occur in the fluidized bed and at

will. As a result, the solids form in the lower part, despite the reaction time required by the technology.

Part of the reaction vessel 10 is a dense fluidized bed, the size of the vessel is only »seconds,

the upper limit of which is 4 and above which a ver

thin gas space is located. 45 share. So the embankment z. B. a grid or

At the beginning of the reaction, the reaction part can show a cellular structure or a honeycomb arrangement,

Takes thereby to the required reaction temperature whose cell longitudinal axes perpendicular through the entire

be brought to temperature that the reaction vessel go from embankment. These cells can be made of light weight

heated outside or the gas feed temporarily consist of sheet metal and a little above the grille or

begin at a higher than the above-mentioned Vorwäimtempe- 50 bottom of the fluidized bed. Their structure is un-

rature or by removing heated solids from substantially, they can be square, octagonal, round

a burner. This method is suitable or have a rectangular cross-section. Your main

especially for a working with two reaction vessels borrowed size requirements are determined by that

Vortex method from the general Λτΐ. which usually they cause blisters or agglomerations

to enable cracking in the presence of a fluidized catalytic converter in the fluidized beds of each cell;

serves lysators; in such a case the one vessel this is usually the case when the relationship

to carry out the desired partial oxidation and the cell length to its effective diameter 5 or

the second is used to heat or cool the fcinver- more.

divided solids serve to the required temperature, As Fig. 2 shows, this can be grid-like or cellular the solids are constantly circulating between the two 60-shaped devices within the main embankment Vessels are guided. Devices that are brought up. Solid particles can move through freely to produce such a cycle of the powdery move the cellular parts up and down. That i-shaped solids between the two vessels are suitable, and the reaction vessel is also equipped with a charging unit the design of the associated system are from line 20 to the introduction of preheated and changed Process known heretofore in which the fluidized 65 vaporized hydrocarbon-oxygen supply lines 21 Solids are used, and do not need here and at the top with a line 22 for withdrawing the products specifically to be described zit. When using one provided, of which the gaseous reaction products too Device with two reaction vessels can be the cooler and other common recovery devices Oxidation processes according to the invention are thereby initiated. The leads 21 lead to a direct the solids in the second vessel through 70 oxygen distribution equipment coming from an upper

U 12

Grid or a perforated tube plate 31 and a In such a case, the hydrocarbon lower tube plate 32 can be made that reads and and oxygen existing feed into the dense only openings for receiving the different layers are blown in on the lowest floor, open distribution pipes 20 ", 20 &, 20c, etc., where the feed is preheated. When out between the plates 31 and 32 are held. The 5 emerge from the dense fluidized bed into the one above Plate 31 is preferably only diluted or gas phase that is preheated to the tubes 27 opposite points punched, but not partially oxyweiter at the loading in the desired way described below, opposed to the drainage areas 28 and then when entering the next higher one overlying surfaces. The fluidized bed extends dense fluidized bed cooled. Of course it is from the grid 23 to the line 29. In this way it is possible to work in a device which has a corrupt through the line 20 in the lower part of the reaction hai tnis wise large number of trays on top of one another containing hydrocarbon introduced through the tubes. In such a case, the compartments are used over the 20a, 206, 20c etc. distributed over the bottom of the fluidized bed middle bottoms both for cooling the reaction, during the through the lines 21 in the of products from the next lower gas phase such as the the plates 31 and 32 formed space introduced 15 preheating and admixing further oxygen Oxygen through the such products contained in the top plate 31, so that the oxygen in this way Holes is distributed. The embankment is blown in above the advantageous in several stages, whereby Grid 23 serves to mix the oxygen and the undesirably high local concentrations of free Hydrocarbons. In general, the temperature should be avoided at some point in oxygen. In the oxygen-hydrocarbon mixture in FIG. 3 is an example of a tower suitable for this purpose Near the grid 23 is set below the reaction temperature.

rature, d. H. below about 300 to 350 ° C. This temperature Fig. 3 shows an alternating emptying and emptying

Temperature can be created by coils or heat transfer zones containing reaction vessel, which is suitable for the

areas are regulated in which a cooling or heating implementation of the hydrocarbon-oxygen reaction

liquid enter through line 24 and through line 25 has been found to be very suitable by the preferred method.

25 can emerge. Here the fluidized beds have a small ratio

The tubes27, which together advantageously have a honeycomb height to the diameter, i. H. less than 1: 1. at can form a good structure at the top and bottom are good swirling of such layers by choosing one Open end. The oxygen-hydrocarbon mixture corresponds to the particle size and gas velocity flows through the open parts of grid 23 and rises 30 the granular solids suppress the reaction, such as through the adjacent tubes 27 upwards. Hereby described above. But meets the mixture of coal becoming suspended solid particles in these pipes hydrogen and oxygen, as already mentioned a zone practically free of solids in the stream of bubbles or agglomerations upwards, so takes place drawn so that the reaction between the oxygen takes place rapidly and in the preferred way, and the hydrocarbon in the resulting vapor. Instead of making the cavities in the form of bubbles filled cavities or bubbles can take place. Those within a single embankment or when being blown up Solids flow into zones 28 - descended from agglomerations of the whirled up solids, in order to then get up again through the tubes 27, they can in the system according to FIG. 3 in rise. The circulation of the solids upwards through which any quantity is generated.

Pipes 27 and down through zones 28 is through 40 the top end 40 of the tower in Figures 3 and 4 can the appearance of bubbles and congestion in common condenser and recovery systems the tubes 27 and the practical absence of bubbles in connection with the one to be oxidized Zones 28 facilitated, so that there the apparent vaporized hydrocarbon at a level similar to that in Density is much greater than in the tubes 27. Cooling Fig. 1 explained manner in its lower part 47 planar or coils 26 can be the temperature of 45 can be carried out. In the drawing, the tower is 40 regulate whirled solids, so that they are in common with three compartments above the floors 41 α, 41 δ and 41c Temperature range between 350 and 450 ° C, but it can also find any other number of floors, in which the reaction can be chosen between the hydrocarbons. Each floor is provided with pipe sockets 42α, 42δ substance and oxygen can still get going. Water, and 42c provided; above these are bells 43λ, 436 Steam or oil are suitable for flowing through the serpentine 50 and 43c in a similar manner as with the usual ones for the gen 26, to remove the excess heat of reaction from fractional distillation. The upper part 30 of the reaction vessel can be attached chromium. Also is located above each be enlarged to the entrainment of the solids soil an embankment of inert turbulent solids the line 22 to reduce substances, e.g. glass beads, the height of which up to point 45λ,

It can be seen from Fig. 2 that the ratio of length 55 is 45 δ and so on.

to the diameter of the entire embankment in the Re- Through the tubes 44α, 44δ and 44c each compartment

Action vessel can be about 1: 1 while the oxygen or air is supplied. These tubes can die

Zones 27, in which the reaction takes place, a caps 43α, etc. easily surround and are perforated so that the

Ratio of length to diameter of 7: 1 or oxygen flowing evenly into the out of the

can have more. 60 lower part or the serrated edges of the caps 43 "

Instead of the desired volume of the vaporous hydrocarbon strones emerging from the reaction

promoting gas phase, as described above, is distributed within. In the embodiment shown here,

To obtain a single high fluidized bed, it is necessary to use about a third of the total in each compartment.

It is also quite possible and often an advantage to add the oxygen in question.

to carry out proper procedures in a tower, 65 in the well-agitated layers on the floors which a large number of relatively flat, dense 41 ", 416 and 41c occur little or none at all Contains fluidized beds on superimposed soils, reacting to. The granular inert solid particles being between two consecutive densities will inhibit the reaction. Thus the layers effect Embankments each have a dilute gas phase, preheating and thorough mixing of acid. 70 substance and hydrocarbon. However, as soon as these two

gaseous reactants in the cavities 46 «, 466 and 46c enter above the corresponding dense layers of the fluidized solid parts, sets a chemical reaction rapidly and usually most of the oxygen added to a layer becomes consumed in the empty space just above this layer.

In any dense embankment, devices to regulate the temperature, such as snakes and pipes, be installed (not shown here). These are used to keep the solid deposits within the desired Temperature range, namely between about 350 and 450 ° C to keep. Bsi another form of implementation of the process according to the invention, the soils be fitted with drainage pipes so that the solids first down through the tower shown here and then to a special liquid cooling tower from the one in the U.S. Patent 2,444,990.

The main reaction products are oxygen-containing compounds such as Ci-C ₃ aldehydes, acrolein, ketones, alcohols, epoxies, olefins, oxides of carbon and water. The chemical side of the reaction and the various possible treatment stages are described in greater detail in US Pat. No. 2,725,344, the description of which, insofar as it relates to the present working method, is included in the present invention. In the reaction vessel shown in Fig. 1, the oxidation products can flow in the vapor state from the upper part of the reaction vessel 10, preferably through a dust separation device such as the cyclone separator 7, and be conducted through the line 8 and the cooler 9 to a recovery plant (not shown). After cooling in the cooler 9, the product separates into a non-condensable gas, a liquid hydrocarbon residue and an aqueous layer. The low molecular weight aldehydes, ketones and alcohols are mostly found in the aqueous layer, while the epoxides and higher ketones and alcohols are present in the hydrocarbon layer together with the olefins and the unreacted hydrocarbon feed. For use as a fuel, it is advantageous resin-forming. To convert aldehydes of the oxidized hydrocarbon layer into more suitable compounds. So you can do the aldehydes

ίο by weak hydrogenation of the hydrocarbon layer into alcohols or convert the various oxygen-containing compounds into olefins by splitting off water. If necessary, the aldehydes and ketones present in the water layer can also be passed through Convert hydrogenation into alcohols.

The following examples serve to illustrate the advantages of the present invention over heretofore known procedures.

example 1

n-heptane was made without use using 0.5 moles of oxygen per mole of heptane in the vapor state oxidized by catalysts. In an experiment according to the previously known working method, an empty vertical Glass tube with a diameter of 64 mm and a length of 40 cm was used as the reaction vessel. With the other Experiment, the same pipe 25 cm high was filled with sand with a grain size of 0.25 to 0.40 mm and the rest proceed according to the method according to the invention, for example as shown in FIG. 1. However, this was not the case Cooling coil applied because the heat losses due to radiation in the surrounding atmosphere are just about to be removed of the excess heat are sufficient. The results obtained are shown in Table 3.

Table 3
Non-catalytic oxidation of n-heptane

Attempt no.
1 I 2

Reaction device
Empty pipe I Blown up sand

Loading speed

Molar ratio of oxygen to heptane

Temperature, ⁰ C

Conversion of n-heptane (in percent by weight)

Selectivity, in percent by weight, for the following compounds

methane

Paraffins with 2 to 5 carbon atoms

Olefins with 2 to 3 carbon atoms

Olefins with 4 carbon atoms

Olefins having 5 to 6 carbon atoms

Olefins with 7 carbon atoms

formaldehyde

Carbonyls with 2 or more carbon atoms

Epoxies

CO ₈

CO

H ₂ O

Total converted

The results of this table show that the degree of conversion despite the higher temperature at swirling solids inhibit the reaction somewhat, as the 70 run 2 is lower. The other results show

8 ecm per minute 0.6 1 8 ecm per minute 1.1] 0.50 6.6 11.0 0.55 3.4 7.5 370 to 380 3.8 j 450 3.0 y 27.8 100.0% 25.5 100.0% 3.2 y ₇
3.9} ^{7> 1} (27.8% ^l - ⁹ \ 32
1.3 J ⁰ ^ (25.5% 9.0 the loading) 5.1 the loading) 6.0 4.2 7.7 6.8 10.2 11.5 1.2 1.0 18.9 28.7 28.9 32.0

however, that this loss of reactivity is more than offset by the beneficial effect of the solids aiii the selectivity of the oxidation. Despite a slightly higher oxygen ratio, only about 7.5 percent by weight of water and oxides of carbon were obtained in test 2 according to Table 3, compared to 11.0 percent by weight in test 1. Another important difference is that the pyrolytic cracking of the hydrocarbon feed by the According to the invention method is strongly suppressed. The germ counts show that the formation of less valuable light paraffins is reduced by more than half, el. H. contained as the feed of 7.1 to 3.2 ⁰ I _0, UNEL atoms the formation of olefin molecules that are less Kohlepstoff to about one-third drops, namely from 22.7 to 16.1 ° / _0th On the other hand, in any new process, the particularly desirable substances, such as C ₇ -OIeImC, ie the simple dehydration products, epoxides and the higher carbonyl compounds, are formed to a considerably greater extent.
5

Example 2

An even greater advantage of the present invention is demonstrated by the use of higher oxygen-hydrocarbon moles relationship"?. For this comparison, n-Hcptane was used in an experiment in an empty tube and in Another experiment in the presence of whirled up glass beads, 50οί * 60μ diameter, oxidized. In each Fall was about 1 mole of oxygen to ί mole of crude hydrogen added. The results are shown in Table 4.

Table 4

Empty pipe

Twirled glass beads

Temperature, ⁰ C

Feed rate (n-heptane), ecm per minute

Molar ratio O ₂ / n-Hcptane

Products received

Liquid hydrocarbon layer in percent by weight based on the hydrocarbon feed

Water layer in percent by weight, based on the hydrocarbon charge

Gas in percent by weight based on the hydrocarbon feed. . . :

Unconverted charge in percent by weight.

The results of Table 4 show that the high oxygen concentration of the feed gases in the presence of the fluidized solids produces a considerably lower reaction temperature than in the empty tube, although in no case was it cooled because of the heat from the surface of the reaction vessel to the environment. More importantly, the gaseous waste products were 32% by weight in the empty tube test, but only 5.5% by weight based on the hydrocarbon feed in the process of the present invention. If one also subtracts the weight of the unconverted charge from the total weight of the hydrocarbon layer, the result is that the oxidation in the presence of the fluidized solids yields about 0.63 parts of valuable products in the hydrocarbon layer for 1 part of the actually converted hydrocarbon charge , while in the empty tube only about 0.51 part of the same product is produced for 1 part of the converted feed. Likewise, in the experiment with the fluidized solids, only about 0.22 parts of undesired solid gas are produced for 1 part of the valuable conversion products in the hydrocarbon layer, while the ratio in the experiment in the empty pipe was 0.71.

Example 3

Table 5 summarizes the results obtained in further experiments which demonstrate the particularly good suitability of a column-like reaction vessel with a number of trays arranged one above the other (see FIG. 3). The reaction vessel used for this had a diameter of 10 cm, a total height of 53 cm and contained three compartments separated by floors, each of which contained a pile of solids above which was an empty space. 550
8.7
1.01

56.5
26th

32
11.5

310

8.5
1.08

85
27

5.5
60

The embankments consisted of glass plates of either 300 or 600 microns in size and served both as a "gasifier" for the mixture of oxygen with the hydrocarbon or with the hydrocarbon oxidation products that have already formed from the reaction zones of the lower stages as well as heat exchangers for Cooling of the warm reaction gases from the zone below. The flow rate of the gases was adjusted so that no noticeable bubbles formed in the solids. As a result, there was a reaction between the hydrocarbon and oxygen, air or oxygen (off-containing gas in the empty spaces above the landfill took place; there was practically no conversion within the layers themselves. The landfills were kept slightly above the temperature required to initiate rapid oxidation. the Amount of oxygen blown into each embankment was regulated in such a way that the temperature rise in the empty space above the embankment left for the person to be oxidized Hydrocarbon wasn't too strong. The warm reaction gases from one stage flowed then into the embankment immediately above and were not cooled down quickly enough before any additional reaction took place;

Leave with the reaction vessel shown in FIG the reaction temperatures can be regulated particularly well within any desired narrow range. As in the Examples 1 and 2 showed, such a control is not possible in an empty pipe.

Table 6 lists the properties of various fluidized solids required for the process of the present invention can be used. Suitable inert solids are substances containing silica, such as sand, glass beads, inactivated clays, clay, coke, and the like. In general, the size of such varies Solids between about 40 and 1000 μ in diameter,

18th

preferably around 40 and 200 μ, if it matters to form reactive vapor pockets in the actual fluidized bed, and between about 300 and 1000 μ, if the embankment is to serve mainly as a non-active gasification or cooling zone. Is it special if it is desired to limit the solid content within the gas bubbles to a minimum, it is still possible larger particles can be used. As Table 6 shows, Axxf beds are the general ones described here Species characterized by a density of the separated layer of about 0.81 to nearly 4.86. At the Blowing through gases to form a dense fluidized bed can be the apparent. Density of such Layer be about 0.5 to 4.3, while the almost solid-free empty spaces or vapor pockets within or between the dense layers create a density considerably below 0.016, even often as low as 0.0016 or less.

Table 5

Non-catalytic oxidation of hydrocarbons in a reaction vessel consisting of three compartments,

each containing a layer and an empty zone.

feed
Dissolving petrol ² ) | Heavy petroleum ³ ) | n-heptane

Attempt no.
112: 3141516

Molar ratio of oxygen to hydrocarbon

Number of places where oxygen is injected

Embankment temperature, ⁰ C

Maximum temperature of the empty zones above the embankments, ⁰ C

Hydrogen conversion,%

Oxygen conversion,%

Weight percent of the feed identified as C and H out non-condensable gas were obtained

Weight percent of feed recovered as liquid products ¹ )

Volume percentage of feed recovered as liquid products ¹ )

Octane number of liquid products ⁴ ) ⁵ ) «)

Octane number of liquid products after adding 0.4 ecm of tetraethyl lead per liter

0.45
3
350

400
28
99

3.5
99.3

95.8
80

79.5
90.5

0.73
3
350

400
43

6.5
96.8

91.7
84.5

93.5

1.0
3
350

410

55
98

9.7
92.0

86.0
88

95.3 -

1.0
3
350 1.45
3
350 400
55
98 410
65
98 8.0 11.5 98.3 92.4 92.8
79.5 85.4
82.3 83.1 87.1

345

410 41 98

7.6 92.9

¹ J Combined hydrocarbon layer after easy hydronning and separation of the organic constituents from the water layer after the entire water layer has been hydrogenated.

² ) Light η η treated petroleum with a boiling range from 44 to 126 ⁰ C from Canadian Itedwatcr crude oil.

³ ) Heavy untreated petroleum with a boiling range from 113 to 202 ⁰ C from crude oil from O.st-Xexas. *) The starting octane number of the dissolving fuel was 67.

⁵ ) The starting number of the heavy petroleum was 43.

The octane numbers were determined using the so-called Fl method (see Erdöl-Lexikon, Verlag Hüthig & Drcyer G.m.b.H., p. 72, top left).

Table 6 Physical properties of the granular solids

Solid

Average particle diameter

Particle density

Density of

deposed

Layer of Reactive Rauni
(discontinued
Layer)

') Free fall speed
speed
m / second

³ ) Aufwirboluagsgeschwin digkcit

m / second

^l ) Specific heat of the

Particle kcal / kg / ° C

Coal dust ...
Glass beads.
Alumina (Al ₂ O ₃ )
Glass beads.
Charcoal semolina ....
Glass beads.
Charcoal semolina ....

35
104
125
308
550
600
1200 to 2400

1.01
2.72
3.68
2.82
1.01
2.82
1.01

0.54 1.67 1.83 1.76 0.51 1.76 0.53 0.47
0.38
0.51
0.38
0.49
0.38
0.48

0.036

0.61

0.91

2.44

2.29

4.57

6.40

Nearly
1/20 of the
free fall speed
speed

0.18 0.20 0.18 0.20 0.18 0.20 0.18

Copper dust 15 8.89 3.03 0.66 0.012

Nickel dust 40 8.89 4.39 0.51 0.36

Aluminum dust ... <45 2.71 1.38 0.49 0.03

Steel balls 400 7.77 4.35 0.44 6.40

Iron spheres .... 520 7.77 4.45 0.43 7.62

Steel cylinder 880 7.77 4.32 0.44 12.20

Steel balls .... 1000 7.77 4.48 0.42 13.7

Steel balls .... 2000 7.77 4.48 0.42 19.8

') 20 to 100 ⁰ C.

²⁾ These speeds correspond approximately to the minimum values required for the initial Aufwirbclung with air at 21.1 ⁰ C and under 750 mm of mercury.

³⁾ Bsi 21.1 ⁰ C and 750 mm of mercury under in air.

909 6B9 / 57S

Nearly
1/10 of the
free fall speed
speed

0.10 0.12 0.23 0.11 0.11 0.11 0.11 0.11

Claims (4)

19 20 Example 4 saturation and increasing branching of the KohJen-Man conducted 9 cm3 of an isooctyl alcohol, the hydrogen, at 380.degree. C., so that more drastic reaction conditions are required by oxo synthesis from a C.sub.1 -Olenn. So z. B. the reaction in which was, together with 1.18 liters of oxygen per minute by partial oxidation of n-heptane in the presence of a vertical tube in the same way as in the fluidized solids at about 260-3O0C 1 and 2 described. The pipe was to be introduced with MuIHt - preferably above about 280C. In the grains. with a grain size of 75 to 100 μ and a comparison to this, the introduction temperature of bulk density of 1.784 filled. The gas obtained above from light untreated petroleum at over 350.degree. C., usually withdrawing from the pipe, was cooled to between about 380 and 4000.degree. C., mainly because of the considerable amount of an aqueous and an organic liquid layer that is normally present in such a layer. The aqueous layer had an acid number of fractionated branched hydrocarbons. 0.072 less equivalents per gram, a carbonyl- In a similar way the effect of the twofold number of 0.482 hundredth! Equivalents per gram and based on the reactivity of the hydrocarbon contained 10.9 percent by weight formaldehyde. The organic isooctane shows at which the temperature at the niche layer had the same acid number, a carbonyl number of 0.543 and an acetyl number of 0.210, depending on the device used. From this and the reaction conditions at about 450 ° C. or higher, it was found that this layer was a considerable amount. Of course you can contain the required amount of esters. Initial reaction temperature for each output to be oxidized. . . _ Determine the partial oxidation of the loads according to the invention by means of preliminary tests. 13.3 cm3 of diethyl ether and 0.85 l of oxygen were passed through a pipe of the same dimensions, the use of which as propellants, the present invention as described in the previous examples, the invention also be very useful in processes, except for the improvement of hydrocarbons per minute , which in turn mullite grains of 75 to 100 μ and a production of oxygen-containing compounds, z. B. contained a bulk density of 1.784 and was 280C warm. 25 Alcohols, epoxies, ketones and aldehydes for the gases withdrawn from the top of the tube would have aims, usually with the hydrocarbons being cooled and the resulting liquid converted to an aqueous and about 25 to 70 percent by weight organic layer. 1111 g were obtained. The total reaction time can be between about 0.1 to organic layer, from which the following fractions are obtained by distillation of a 10 second, preferably about 0.5 to 3 seconds for a sample of 400 g: 30 each stage, i. H. after each introduction of oxygen. 1. Boiling range 20 to 24 ° C: 54 g, mainly acet- More generally oxidizable organic verbaldehyde fertilize for at least about 1 second at tem- 2. Boiling range 24 to 33.5 ⁰ C: 40 g of unconverted temperatures between 300 and 500 ⁰ C are stable, and ethers are preferably those that contain substantial amounts of methyl 3. Boiling range 33 to 35 ° C: 239 g, half of which contain water bonds, according to the invention Soluble was process to be partially oxidized. 4. Residue: 67 g, mainly acetic acid. The oxygen is advantageous in proportions The above description and examples refer to a total of about 0.3 to 1.5 moles of oxygen per mole of Admittedly, on petroleum-like hydrocarbons in all-hydrocarbon feed; the local common and n-heptane in particular, but concentrations can be considerably below these point out that these are merely preferred or crude values, and the overall ratio can vary up to Increase terude embodiments of the present invention to about 1.75 when subdividing the oxygen. Rather, the present invention is different with amounts on different levels of floors Effectiveness not only blows to partial oxidation. Pure oxygen is preferred here, however a large number of hydrocarbons, but 45 can also contain gases with relatively low levels of acid smoke for partial oxidation of other organic compound concentrations, e.g. B. air, as an oxidizing agent fertilize, so z. B. of alcohols, ketones, aldehydes, can be used. In such cases, however, is at aliphatic amines, ethers and esters, applicable. the extraction of the raw products obtained a stronger The main requirement is always that the initial washout is required to avoid undesirable losses substances at the reaction temperatures, which are usually avoided in valuable fractions. Furthermore lie between 300 and 45O ⁰ C and below the reasonable can be for the inventive partial oxidation to applied working pressure are gaseous. Press up to the point or in addition to oxygen also gaseous oxygen 10 atmospheres, preferably 1 atmospheres, are suitable. Use inert transmitters such as di-nitrogen tetroxide. Diluents, e.g. B. steam or nitrogen, it should finally be noted that the in for the promotion of a possibly additionally required multistage 53 Fig. 3 shown, possibly without vortex Suitable for evaporation. Do you work z. B. shift operated device also for implementation Steam and atmospheric pressure are used in the reac- different reactions in succession tion zone, so you can treat starting materials in it, can be. So z. B., as described, in the whose normal boiling point may be up to about 600 ⁰ C. lower parts of the reaction vessel, ie after the The invention is particularly useful for the selective first oxygen feeds into the reaction vessel, carbon oxidation of normal or monomethyl-substituted hydrogens in the presence of inert solids, oxidizing paraffins with about 5 to 16 carbon atoms in the mole while cooling in the upper parts of the reaction vessel. Good yields of valuable oxidation products, however, in the presence of suitable oxidation products, the oxidation products are obtained in a similar manner using appropriate known catalysts, such as alumina or chromium oxide, which can also be dehydrated or dehydrated from lower molecular weight paraffins,
nen (ie those with 1 to 4 carbon atoms), from the corresponding olefins and from naphthenes, such as PATENT CLAIMS: Cyclohexane, methylcyclopentane and methylcyclohexane. 1. Method of homogeneous, non-catalytic In general, the reactivity of the molecule decreases. Partial oxidation of oxidizable organic compounds with decreasing molecular weight, increasing bonds in the vapor state, characterized in that that in a reaction vessel a stream of vapors of the organic compound alternately from bottom to top through many spaces filled with inert, finely divided, fluidized solids and many of these inert solids almost free spaces (gas pockets or gas bubbles), the solid-poor spaces, Gas bubbles or pockets, in which the reaction of the gaseous starting materials takes place, are several times larger than the spaces between adjacent solid particles in the solid-containing spaces, so that the stream of vaporous organic compounds in the almost solid-free spaces at reaction temperatures between 275 and selectively oxidizes 480 ⁰ C for up to 10 seconds with a gas containing free oxygen, the local molar ratio of the free oxygen to the organic starting compound being at most 1.25, so that the vapors obtained by the selective oxidation are used to discharge the excess Sigen heat of oxidation is introduced into a fluidized bed containing the inert solids, the finely divided, inert solids of the fluidized bed cools, the oxidation products are withdrawn from the top of the reaction vessel and worked up in a manner known per se. 2. The method according to claim 1, characterized in that the solid particles have a particle size of about 40 to 1000 μ and a bulk density of about 0.8 to 4.8. 3. The method according to claim 1, characterized in that the oxygen-containing gas is blown in at several, height according to different points of the reaction vessel in such an amount that the entire Molveihalteiüs of free oxygen to the organic starting compound between 0.3 and 1.75 And the residence time of the oxygen blown into the solid-free spaces at 275 to 480 ⁰ C is a maximum of 3 seconds. 4. The method according to claim 3, characterized in that the organic starting compound is used Uses hydrocarbons that contain up to 16 carbon atoms and predominantly methylene groups, the local molar ratio of free oxygen to starting hydrocarbon at each Position of the device is at most equal to 1. Considered publications:
German Patent No. 900,984;
French patent specification No. 919 118. 1 sheet of drawings & 909 689/578 12:59