DE1592844A1 - Process for the production of carbon black - Google Patents

Description

PATENT ADVERTISER *: 1 5 9 2 8 A 4

DR.-ING. BY KREISLER DR.-ING. SCHÖNWALD DR.-ING. TH. MEYER DR. FUES

COLOGNE 1, DEICHMANNHAUS

Cologne, 25-8.1966 Kl / Ax / st

Cabot Corporation,

125 High Street, Boston, Massachusetts 02110 (V.St.A.).

Process for the production of carbon black.

The invention relates to an improved method for producing carbon black using a carbon-forming method Flame enveloped in a dense cloud containing soot suspended in a gaseous medium is, preferably from by-product gases of a carbon-forming incomplete combustion reaction consists.

There have been proposed methods in which flames are used that burn in environments caused by such clouds of soot and gaseous combustion products formed v / earth. However, the products of these processes have some drawbacks. In the case of Sidelsweise, the procedure which is the subject of U.S. Patent 2,779,665, normally a carbon black obtained from relatively coarse particles exists and is greyish in color and is unsuitable for many purposes. Another process that involves a flame that burns in a people rich in Is carbon that is produced as a combustion product

Subject of the German patent (patent application

C 38 983 IVa / 22f) of the applicant. In this process, the addition of primary oxygen, i.e. oxygen that the Flame fed through the burner is required to

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Obtaining a carbon black with good color properties in high yield, of course, can follow the teachings of the latter Patent and the present description can be combined by those skilled in the art in order to achieve optimal results.

The invention relates to a method for production of soot using a flame enveloped in a carbon-rich cloud of combustion products, with increased product yields by regulating the furnace pressure are achievable without the quality of the carbon black formed being essential to deteriorate. The procedure can be proportionate simple apparatus and results in a soot of improved quality.

According to the invention, it has been found that when a hydrocarbon and a gas containing free oxygen are reacted under pressures which are somewhat higher than those normally used in soot production, surprising and unexpected product yields can be achieved if the reaction is carried out within a cloud of smoke that is formed by the smoke-like reaction products of the combustion. For example, when using a typical burner, if the pressure in the furnace in which the soot is produced is increased from normal pressure to a pressure which is only 7 mm Hg above normal pressure, an increase in yield of 32 ^c / o can be achieved . Furthermore, using a typical burner, the yield at a pressure of 7 mm Hg above normal pressure, the yield is 41 'jo higher than the yield that would be achieved at the pressure of 51 mm water under normal pressure, which is described in U.S. Patent 2 779 665 is prescribed for the procedure described there. It is highly surprising that the product yield in the process according to the invention can be increased without any significant deterioration in the advantageous properties of the product obtained. As an alternative, the depth of color of the product can be improved by operating according to the invention at higher pressures, but using a slightly higher proportion of oxygen in the flame

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and et '.: as lower. exploits than they can otherwise be obtained in purchase ■ -enomines.

Accordingly, the invention relates to a method for the production of heat by incomplete combustion of gaseous hydrocarbons with permanent material in a constant, non-turbulent, upwardly inclined lamp. The process is characterized as "·" of the upper ^i; eil del · flame is enveloped by a dense üaucluvolke surrounded and which are kept at a pressure \. 'IRD, which is somewhat higher than ITormaldruek.

The invention is described below in connection with the figures be s erieb.

Pi'·. 1 shows scixematiscii a burner, which is to the formation a relatively non-turbulent? flame that has viohldefiiiierte benaclibr.rte tongues

Ii ¹ Ig. 2 is a graphical representation that shows the increase in the ^ .. Figure 1 shows the apparatus in which the combustion process is carried out.

the invention is an incomplete, soot-forming Combustion reaction advantageously carried out in a comb, in which the liaiipt reaction participants separated with the help of earth feed lines introduced in close proximity to each other, uiiiie such plams can be used in any suitable ./eise i.'ür the purposes of the invention are generated. For example 111.3 is a relatively non-turbulent flame with create well-defined zones easily in a burner of the i'ype, i.e. the one in -Fig. 1 is shown and arranged concentrically Has lines. The flow rates of fuel supplied to the device and the size and the length of the pipes are not in themselves critically important, as long as a stable flame covers the adjacent zones a gaseous hydrocarbon and a free oxygen containing gas is formed. In general

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In my opinion, it should not be difficult for a person skilled in the art, who is familiar with the information given here, to apply the procedure in accordance with of the invention to carry out because carbon-forming flames of the type discussed above are well known in the art.

According to the invention, at least the upper part of the reaction flame is advantageously enveloped by a cloud of smoke consisting of a relatively inert gaseous medium that carries soot with it or contains it in suspension. The exact proportion of the length of the flame which is enveloped by such an oil can vary depending on the flow rates, the geometry of the flame and the reaction chamber, the ratio of the total free oxygen to the hydrocarbon, and so on. Generally, however, should be about 25 to 90 fs, preferably about 35 - 80 of the total length fo the flame of this V / olke be wrapped. If more than 90> ί of the flame is enveloped by this cloud, an unstable flame normally results. Accordingly, at least about the lower 10 % of the flame is preferably not enveloped by the said cloud.

The cloud of smoke can be formed in any suitable way will. A generally suitable method of starting up and for the formation of the people this happens as follows:

A hydrocarbon, preferably a gaseous hydrocarbon, which is then used to generate soot is mixed with a gas that contains free oxygen, incompletely reacted in a closed chamber, with a strong sooty flame being formed. The chamber must be provided with devices for removing the soot formed and the gaseous by-products, but these will Exhaust devices partially blocked or blocked during the start-up time, so that less soot and gaseous By-products are removed as are formed by the reaction. The maintenance of these conditions for a period of time has the consequence that in the upper A comparatively thick cloud is behind the chamber.

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which mainly consists of soot and gaseous by-products of the soot formation reaction. As the yolk gets thicker and bigger, it crawls down into the chamber. V / hen the bottom of the 1 / olke the desired proportion of the flame, which normally j approximately 90>, preferably about 35 to 80 fo the amounts to flame, has wrapped, the outlet devices are set again, that then an equally large Length of hit peoples consisting of soot and gaseous by-products are withdrawn as each is formed. The amount of the hydrocarbon introduced into the flame and the amount of oxygen are also adjusted as needed within the above-mentioned limits. The outlet device expediently serves at the same time to regulate the truck within the chamber. Additional slides or flaps, which are arranged next to the outlet, can also be used to regulate the pressure. The overpressure ".-:. Ird preferably between about 1 atmosphere and 100 egg -I _r kept above 1 atmosphere order excellent yields ensure en without excessive operations difficulty to create advantageously an overpressure between et v / a 5 and 10 mm Hg complied with.

To eil'ii. it is appropriate to use hydrocarbons, z.3. Heating oil Mr. 2, .ZyI oil, benzene, distillate fuels, residual oils u.d-'L, to be introduced into the flame produced by uie combustion of the "on-shaped" hydrocarbons formed by these Normally liquid hydrocarbons can be found in the form of e.i.n '- tj leads or into the!' 'lambs are sprayed. the Lenge '.erj introduced into the flame, usually liquid. Hydrocarbon X3t is generally not critical important. Know up to about 6.7 1 of the liquid every hour Hydrocarbon per ITm of gaseous hydrocarbon proved to be quite suitable for the method according to the invention. It can also be vaporized liquid hydrocarbons as the only use of hydrocarbons be used in the method according to the invention

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Unsaturated gaseous hydrocarbons with less as 5 carbon atoms in the molecule, e.g. acetylene, ethylene, Propylene and butylenes, however, are the most preferred major ones Starting hydrocarbons.

It is not intended to be bound by any theory as to the mechanism of action achieved by employing the ancestor of the present invention, but it is believed that the presence of the ott-formed fluorescent particles contacting and enveloping the upper, normally destructive areas of the reaction flame , the o;: ydative and water-destroying reactions which normally reduce the number of growing .Au 5 particles in the ιθκΙ: - ionic flame. In each jail has the j ^ r.vesenheit the ftauchwolke to the upper portions of iPlarjae au £ err-ev.'rhnliche RuSausbeuten to 'sequence when the "Vorfahron - ^ e measured carried out the teachings herein v / ill be further. these increased yields are not achieved at the expense of a substantial change in the parbe properties of the raises.

l) ?. s .. ^; esen the invention and the. _: ver.i £ LG of iirfindum-; The products obtained are illustrated by the following specific embodiments.

1 (comparison search)

Mr attempt v / urde the ⁿ in i ig. 1 'is used, in which the cylinder 2 was made of GI: s and had an internal diameter of 102 mm and a length of 102 cm, and in which the burner 4 (in J? Iv. 1 of the German patent (patent application C 38 983 IVa / 22f) type shown), which has an outer diameter of 9,? rom and a length of 35 ram, about in the middle of cylinder 2 and about 51 mm above which ./and 14 was arranged. The line 10, which was provided with the control valve 12, was connected to the upper end of the cylinder 2. JÜe line 10 led to a (not shown) Husk deposition system, which consists of a

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There was a blower and three cyclones connected in series with a subsequent bag filter. I, ^r oh the starting, at the ungefu.hr to the top 76 of the cylinder 2 cm a dense surging 'people of HNC and xiebenproduktgasen using a ru. When the acetylene-air flame was formed, 0.34 Hnr acetylene per hour was continuously fed in via line 16. No gas containing free oxygen was introduced through line 18 in this experiment. Instead, 42.5 ITl of nitrogen per hour were fed through line 18. However, 1.56 Hm of air per hour was supplied to cylinder 2 through line 2C. Jas valve 12 was brought into a predetermined position, which enabled a rapid increase in the pressure in cylinder 2 to normal pressure.At the same time, a soot-forming flame was formed, which would normally have a length of about 50 cm, the upper part of which was 33 cm in this case, however, was enveloped by the mentioned V / ο Ike. After about 5 hours in which a total of 318 g of 3 ounces were collected, the experiment was terminated. The collected huss was analyzed. It had an ITigrometer value of about 87 and a mean particle diameter of 25 m / u (determined by electron microscopy).

Example 2

The device shown in FIG. 1 was used for the experiment was used in which the cylinder 2 was made of glass and had an inner diameter of 102 mm and had a length of 102 cdi, and in which the burner 4, which had an outer diameter of 9.5 mm and a length of 35 mm about in the middle of the cylinder 2 and 5 mm across the V / and 14 was arranged. To the top of the cylinder was the line 10 connected to the cone valve 12 was provided. The line 10 led to a (not shown) Soot separation system consisting of a blower and consisted of three cyclones connected in succession with a subsequent bag filter approximately in the upper 76 cm of cylinder 2 a density

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surging 'cloud of soot and by-product gases with a resting acetylene-air plane. ^v ) In this experiment, no gas containing free oxygen was introduced through line 18. Instead, 42.5 ITl of nitrogen per hour were fed through line 18. However, 1.56 ITl of air were introduced every hour Cylinder 2 was fed through conduit 20. Valve 12 was set to a predetermined position which allowed the pressure in the cylinder to rise rapidly to 4.1 mm Hg, creating a soot-forming flame, typically about 50 cm in length would have the upper I ¹ ecause of 33 ', however, all of the above' cm in this! '/ olke was wrapped. iiach 5 hours with a total of 340 g of carbon black were collected, the experiment was discontinued. the collected soot was analyzed It had a 1.igrometer reading of about 87 and an average particle size of about 25ovu (determined by electron microscopy).

Example 3

For the experiment it was done in Jiig. 1 shown device used in which the cylinder 2 is made of glass was and had an inner diameter of 102 mm and a lün-e of 102 cm, and where the burner 4, the an outer diameter of 9.5 mm and a length of 35 mm had, about in the middle of the cylinder 2 and 51 mm over the ./and 14 was ordered. At the top of the cylinder the line 10, which was provided with the cone valve 12, was connected. The line 10 led to a (not shown) Soot separation system consisting of a fan and three cyclones connected in series with a subsequent Bag filter existed. Jach ti em start-up where approximately in the upper 76 cm of cylinder 2 a density billowing whey made of soot and by-products with one half πι. · .end acetylene-air-Plamme was formed, were! from continuously constant 0.34 l to acetylene with: by means of the pipe

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16 of the line G supplied. In this experiment, no gas containing free oxygen was introduced through line 18. Instead, 42.5 μl of nitrogen per hour were fed in through line 18. However, 1.56 ITm of air per hour were supplied to cylinder 2 through line 20. The valve 12 was placed in a predetermined position which allowed the pressure in the cylinder to rise rapidly to 5.0 mm Hg overpressure. This formed a ruiT.bilden.de plamme, which would normally have a length of about 50 cn, the upper veil of 33 cm in this pail, however, was encased ^{by the renamed. <: Olke.} The experiment was terminated after 5 hours, during which a total of 363 g of husk were collected. The collected soot was analyzed, it had an ... ir gromet er value of about 87 and an average particle size of about 25 m / u (determined by electron microscopy).

Example 4

Purely the experiment was the one in Pig. 1 is used, in which the cylinder 2 was made of glass and had an inner diameter of 102 mm and a length of 102 cm , and in which the burner 4, which has an outer diameter of 9> 5 mm and a length of 35 mm had, roughly in the cement of the cylinder 2 and 51 mm above the ^f v7and 14 was arranged. The line 10, which was provided with the control valve 12, was connected to the upper end of the cylinder. The line 10 led to a soot separation system (not shown), which consisted of a fan and three cyclones connected in series with a subsequent bag filter, after start-up, in which approximately in the upper 76 cm of cylinder 2 there was a dense surging Yfolke of soot and by-product gases was formed with the aid of a sooting acetylene-air flame, 0.34 Hin of acetylene per hour were continuously fed with the aid of line 16 to line 8. No gas containing free oxygen was introduced through line 18 in this experiment. Instead, 42.5 Nl

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Nitrogen was supplied through line 18. However, 1.56 Fnr of air was continually supplied to cylinder 2 through line 20. Valve 12 was placed in a past three-quarters position which allowed the truck in the cylinder to rapidly increase to 7 A soot-forming JPIaHi e formed, which would normally have a length of about 50 cm, the upper part of 33 cm of which, however, was encased in this fur by the above-mentioned people The attempt became 5 hours, in which a total of 390 g of ice were collected. " canceled uer collected soot was analyzed. It had a liigrometer value of about 87.5 and a mean particle size of about 26 nyu (determined by electron microscopy).

Example 5

1 " ^{1 For} the experiment, the device shown in i'ig. 1 was used, in which the cylinder 2 was made of glass and had an inner diameter of 102 mm and a length of 102 cm, and in which the burner 4, the one Outside diameter of 9 »5 mm and a length of 35 now had, approximately in the middle of the cylinder 2 and 51 mm above the V / and 14. The line 10 was connected to the upper end of the cylinder, which with the cone valve 12 The line 10 led to a soot separation system (not shown), which consisted of a fan and three cyclones connected in series with a subsequent bag filter Clouds of soot and by-product gases were formed with the aid of a sooting acetylene-air flame, were continuously fed hourly; 0.34 Hm acetylene via line 16 to line b. In this experiment, no Ga a containing free oxygen is introduced through line 18. Instead, 42.5 Nl of nitrogen per hour were fed in through line 18. However, 1.56 Nm ^{5 of} air was introduced into cylinder 2 through line 20 every hour

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leads. uas valve 12 was in a predetermined .S n "· .-;: ebrr.Glrt, f <ie a rapid rise in the pressure in the cylinder to 4.1 ram \ ^γγ overpressure. Here r ic Ii cine ru - Formative I ⁽¹ laiiii..e, diti normally show a L, χι · ο γοη about 50 cm have v.rrde, the upper x'eil of 3 "y cm in this IVIl, however, enveloped by the renamed '..' ollce was.: .rc: i '■} otunden, in which ins. ^ esai.t 4C4 β ^ ^u ^ fufrefaneii v.xirden, u-north of the Yersucli broken off, ^ he refanrene. air was M.alysed. L ^ r had an I. "i, '; - roir.eter \ vert of about SC and a mean particle size of about 25 m / U (electronc; ni".; roükopisch tuned).

! ^ ■■ ^ t 'rlich ind in üalmen the Jirfindung numerous ^ nderunren hinsichtlicli the anrcerebeiien -Brennstoffe, I..en ^f enverhältni ^ se and _"-edin% unren i: K' ^r iich" ^ eispiels'.veise it is selbstvernf ndlich, represents ö.er in performing Ürfindunf: under Änv.endun-: higher pressures verhiiltnismiifiif _t r: oelcundiirluft horses Henren or oekundrrsauerstoff the Plamme must be sugefiihrt.

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Claims (8)

Claims 1) Process for producing soot by incomplete combustion of gaseous hydrocarbons with oxygen in a relatively stable, non-turbulent, upward direction Flame, characterized in that the upper part of the flame is enveloped by a thick cloud of smoke and is surrounded, which is maintained at a pressure slightly above normal pressure. 2) Method according to claim 1, characterized in that a pressure of about 1 to about 100 mm Hg above normal pressure can act on the cloud of smoke and the combustion reaction taking place in it. 3) Method according to claim 2, characterized in that one maintains a pressure between about 1 and about 10 mm Hg. 4) Method according to claim 1, characterized in that a small proportion of the total oxygen of the flame as Primary oxygen adds. 5) Method according to claim 1, characterized in that the hydrocarbon vapors largely consist of unsaturated gaseous Consist of hydrocarbons. 6) Method according to claim 4, characterized in that the unsaturated gaseous hydrocarbons consisting mainly of unsaturated hydrocarbons with less than 5 carbon atoms, preferably acetylene. 7) Method according to claim 1, characterized in that the hydrocarbon vapors mainly consist of vaporized liquid Consist of hydrocarbons. 109808/1629 15928A4 8) Method according to claim 1, characterized in that the hydrocarbon vapors consist of vaporized liquid "Hydrocarbons enriched gaseous hydrocarbons put together. 109808/1629