DE2436370C3 - Process for the conversion of organic chlorine compounds - Google Patents

Description

4. The method according to claim 1 to 3, characterized by combustion at very high temperatures (I500 ^c C), characterized in that the conversion is carried out and that additional fuel, organic chlorine compounds in the fluidized bed »5 z. B. hydrogen is required. Another disadvantage is performing. "consists in the fact that the

5. The method according to claim 1 to 4, characterized in that the hydrogen chloride is strongly marked by the, that a partial amount of the nitrogen introduced into the catalytic converter is diluted. lysators from the reactor discontinuously or the with the organic chlorine compounds and the continuously withdrawn, hydrogen introduced in a regeneration stage 30 becomes a which is converted into water during the conversion on the catalyst, so that in addition A larger carbon formed by burning off with hydrogen chloride during work-up containing oxygen «!! Gas removed and the so regene- amount of water accrues, which the recovery of konrierte Catalyst in the reactor for conversion-centered hydrochloric acid and its chemical conversion of organic chlorine compounds. When destroying organic leads. Chlorine compounds, which also contain nitrogen,

the serious disadvantage is the formation of nitrogen oxides during combustion, which is

tion to the formation of nitric acid with the hereby

40 associated disadvantages (contamination of hydrochloric acid, Corrosion).

The present invention relates to a method There has now been an improved method for converting

for the conversion of organic chlorine compounds into the conversion of solid, liquid or gaseous gases containing carbon and hydrogen chloride. organic chlorine compounds to form In many chemical processes fall organic 45 hydrochloric found that characterized gekennzeichnische chlorine compounds as by-products, is net that the organ Sichen chlorine compounds which are no longer used in general, can operate at temperatures from 300 to 1200 ⁰ C in the presence of and must be destroyed, a solid catalyst, the carbon or a destruction causing technical difficulties and high element of the third and / or fourth main group of costs. In many cases it is difficult to carry out the 50 periodic table in the form of oxygen compounds destruction of the organic chlorine compounds with the formation of elemental carbon compliance with the existing legal provisions and a gas containing hydrogen chloride via exhaust air and waste water. It's decomposed. In the process according to the invention, various approaches have been taken to break down the problem that the organic chlorine compounds dissolve in the form of carbon, the destruction of organic chlorine compounds to form a substance and a gas containing hydrogen chloride. The process is carried out in such a way that the carbon adsorbed on the catalyst during the conversion of organic chlorine compounds for the hydrogenolysis of aromatic chlorocarbons is known from US Pat. No. 35 95 931. The reaction is carried out in the beer, so that a carbon-free gas is obtained gas phase with hydrogen using 6o. In addition to hydrogen chloride, the gas can contain other palladium or platinum-containing catalysts. B. hydrogen and hydrocarbon carried out. For example, chlorobenzene is contained by substances such as methane, ethane, or benzene. The hydrogen chloride can be converted in a known manner from reaction with hydrogen to give benzene and chlorine gas. Separate the application of this process hydrogen, z. B. by absorption in rens on the destruction of organic chlorine compounds 65 Water with the production of a concentrated salt gene has a number of disadvantages. It'll be acidic. This hydrochloric acid can be required for a wide variety of very expensive noble metal catalysts and can also be used for other purposes, e.g. B. for chemical hydrogen as a raw material. The catalysts have syntheses for the regeneration of ion exchangers

for the recovery of boiler feed water and other borrowed carbon can in a suitable manner more. It is also possible to remove the hydrogen chloride after, for. B. by burning with air,
known methods, e.g. For example, by electrolysis, in I _n a preferred procedure will convert Kataly hydrogen and chlorine, and used in this capacitors, the SiO. and Al ₂ O ₃ contain, the way the chlorine contained in the organic chlorine compounds is recovered in elemental form under the name "fluid cracking catalysts". Catalysts for the catalytic cracking of mines are used industrially for the conversion of organic chlorine-veral oils (see Ullmann, Vol. 6, compounds used, which consist of chlorinated hydrocarbons [1955], pp. 632 to 633 and American petroleum furnaces, so will Obtain an exhaust gas which contains water Refining, D. van Nostrod Comp., Inc., New York, free hydrogen chloride. This water chloride io 4th Edition, Editor HS BeIi, 1959, pp. 240 to 263).
substance is obtained in concentrated form. Further constituents The reaction can be carried out in a fixed bed, moving bed or parts of the gas are, in particular, hydrogen, methane, fluidized bed. In a preferred or benzene. If chlorine compounds are used for the conversion of the organic embodiment of the process according to the invention, which, in addition to the EIe, also contain oxygen with a fine-grained catalyst in the fluidized elements C, H, Cl, then work is carried out for 15 beds. The grain size can be 10 to 1000 μ, the oxygen in the exhaust gas in the form of carbon dioxide, z. B. 50 to 150 μ.

Obtain carbon oxide or water. Also in this The catalytic conversion is at 300 to the case wiri a concentrated hydrogen chloride stream 1200 ⁰ C, z. B. obtained at 500 to 1000 ⁰ C or 600 to 800 ⁰ C, which contains little or no water. At carried out. The residence time is, for example, the use of organic chlorine compounds which have the EIe "1 second to 1 min, for example 5 to 20 seconds.
elements contain C, H, Cl and N, the nitrogen is obtained from the exhaust gas as molecular nitrogen (N ₂ ) for the economy of the process. Meaning that the conversion of the organic Even when using organic chlorine compounds, the chlorine compounds with inexpensive catalysts contain the elements C, H, Cl, O and N, the and without additional heating materials, such as. B. obtained hydrogen, nitrogen in molecular form as N ₂ . 25 natural gas or heating oil. In a particular embodiment of the process according to the invention, the process according to the invention is carried out during the conversion, when several exothermic and endothermic reactions take place. The cleavage of the organic chlorine compounds to form carbon-laden carriers with oxygen-carbon and hydrogen chloride-containing gases is in gases such. B. with air, freed from carbon, 3 <> generally exothermic. This cleavage heat can be obtained, an exhaust air stream which, in addition to nitrogen, can be used to convert the material and oxygen into carbon dioxide. The catalyst regenerated in this way is applied to the organic chlorine compounds and is heated in the steam reactor to the conversion temperature to convert the organic chlorine. In general, the overall reaction in the bond in carbon and hydrogen chloride is endothermic, ie gas containing energy must be recycled here. The regenerated catalyst will lead. The burning off of the carbon in the generator can be carbon-free or carbon is removed. Regenerator is an exothermic process. Part of the hold. It is essential that over longer periods of time the heat generated here can be removed for heating the carbon formed in the reactor, the air required for both combustion being used, for example by burning off with air. 4 ° the excess can be used to supply the flawed energy in the reactor for the conversion of the organic chlorine sludge. The rain compounds used contain catalysts that can be operated so that carbon or elements of the third to fourth a desired temperature is established in the reactor. In the Ge main group of the periodic table in the form of complete processes, after the conversion of the orga-oxygen compounds. As elements of the third 45 niche chlorine compounds obtained a gas stream, the and / or fourth main group of the periodic table after separation of the hydrogen chloride from combustible (Mendelejeff) come into consideration boron, aluminum, ren gases such as hydrogen, methane, benzene. Carbon, silicon, germanium, tin. As a catalyst, the components of this gas can - if generators are used, for example: carbon, if desired - isolated and a chemical use silicon dioxide, aluminum oxide, titanium oxide, aluminum 5 »can be added. You can also use vernium silicates, zeolites as heating gas. The catalysts can be used. In the regenerator hot smoke sets are obtained from other elements in the form of the elements gases whose energy content contains in a known manner or their compounds, such as. B. lithium, can be exploited.

Sodium, potassium, magnesium, calcium, zinc, boron, very high levels of converted earths, phosphorus, vanadium, bismuth, chromium, 55 degrees of organic chlorine compounds in carbon molybdenum, tungsten, U / an, iron, cobalt, nickel . The components of the catalyst can be varied, for example 95 to 100%. The catadic form are present, e.g. B. as mixed oxides or spilytic conversion of organic chlorine compounds nelle. The catalysts can have various physical properties based on 4 reaction equations, z. B. an inner upper ^6o visual light:

Area (according to BET) from 1 to 1000 m ² / g It is advantageous _{c H} q _ ^ _HC , _{+ CH + 2} C + H

liable to use catalysts that have a surface area C ³ h'c1 -> 2 HCl + 6 C + H *

of> 100 m '/ g, e.g. B. 300 to 600 m '/ g. Be c'h ^ CI -> HCl + CO ₂ + C + CH ₄

Preference is given to using catalysts which have a high _{c H NC} I _ ^ _H q , ,, _N _ | _ ₅ (-. _ | _ 3 / jj

have mechanical and thermal resistance. ⁶ 5 ^{5 4} ' ^{2 2 n}

As a catalyst, carbon, e.g. B. in the form As final products for the conversion of organic

activated carbon. Organic chlorine compounds are suitable for Umnic

Conversion of the organic chlorine compounds additional compounds in pure form or in the form of

5 6

mix whose elemental analysis carbon, water products can these before entering into the reagent and chlorine, and optionally other elements, can be evaporated. However, it can also be used in such as oxygen and nitrogen. In order to be able to do so in a fully suitable manner, e.g. B. by spraying with the help Constant conversion of the chlorine into chlorinated water from nozzles, in liquid form in the fluidized bed reactor In order to be able to reach material, it is advantageous to give charge C and at the same time evaporate and become carbon products to be used based on the elementary substance and the analysis of hydrocarbons and hydrochloric acid convert a ratio of at least 1 atom of water to gases. Solid products can be in front of the substance to have 1 atom of chlorine, z. B. 1 to 5 atoms entering the reactor melted or with others Hydrogen per atom of chlorine. In those cases where products are brought into solution by mixing organisers chlorine compounds are to be destroyed, which are i °. In those cases where decomposable or easily a ratio of less than 1 hydrogen atom per coking liquid or gaseous product vice versa-1 Have chlorine atom, one can work in such a way that to be converted, it is advisable to use special to take other organic technical measures intended for destruction, e.g. B. the use connections mixed in, so that in the resulting manure cooled nozzles and the use of a Mixture a ratio of at least 1 atom of water-15 high pressure to the products in the hot hydrogen is present per 1 atom of chlorine. Sample catalyst to be injected. It can be beneficial for wise one can use an essentially from hexachlor- the manufacture of these nozzles special materials to verbutane Turn the existing mixture with a mixture in order to avoid corrosion Mix rer alcohols so that avoid the ratio.

Hydrogen to chlorine = 2: 1. However, you can * ° R "" 1 1

also organic chlorine compounds with a ver e 1 s ρ 1

ratio of less than 1 hydrogen atom per 1 chlorine In a reaction tube of 2 m length and one atom in the conversion without admixing other diameters of 50 mm, 1 1 of a commercial compound was used. In this case, a cracking catalyst with an aluminum in addition to carbon on the catalyst, a gas having an oxide content of 13% and a silicon dioxide content in addition to hydrogen chloride, organic chlorine compounds of 87%, is obtained. The catalyst had a medium contains. This organic chlorine compound can be used with a grain size of 100 μ. In the reactor was by gene, z. B. low chlorinated hydrocarbons, isolate a nozzle every hour an amount of 1 kg of an organ and another use. This arnian chlorine-containing waste product, which, on the basis of some examples, can be entered for the case of the conversion of 3 ° of the elemental analysis to 38% carbon, 5% hexachlorobutane by the following equation - hydrogen and 57% chlorine: the cleavage to carbon and hydrogen chloride-9 H r η -ν 8 nn 4- rri j_ ι r containing exhaust gas was carried out at 800 ⁰ C. The ζ u ₄ n ₄ v, i _e - ^ - δ riLi + Lu ₄ t / L _{bd of the cleavage} was completely

Adsorbed on the surface of the catalyst even at a ratio of less than 1 water- 35 dig. It was

atom per 1 chlorine atom can be obtained (e.g. by one made up of hydrogen chloride, hydrogen and methane

Lowering the gap temperature) the conversion, existing exhaust gas is preserved. The reactor became

if desired, steer in such a way that the hydrogen chloride continuously removes a partial stream of the catalyst.

Gas containing lower organic chlorine compounds by burning off carbon with air

contains fertilizing. This procedure can be freed by the 4 ° and then returned to the reactor.

Equation The amount of the catalyst circulating became like this

2 C H Cl -> 4 HCl 4- CCl + 2 CH 4- 5 C regulated that the carbon content in the used

^{464 4 4} catalyst was about 6%,

illustrated. _. · 1 9

For the conversion of the organic chlorine compounds, a wide variety of chlorinated products are suitable Desired by-products arise, for example, a grain size of 0.1 to 1 mm filled. In the distillation preliminary runs, intermediate runs and residues, the reactor was obtained through a nozzle every hour during the distillation, furthermore chlorine-containing gaseous 5 ° of 120 ml of dichloropropane and a stream of nitrogen, which were introduced for example at circulating gas of 30 l. The cleavage was carried out as a side stream and destroyed ^{at 600 ° C. processes.} The coal pastures formed during the split must. If gaseous substances are used, the substance is completely on the surface of the catalyst, these can be fed directly into the reactor, in which it is also adsorbed. An exhaust gas consisting of hydrogen chloride, water, for example, the catalyst located in the fluidized bed, 55 substance and methane was obtained. That will be entered. When using liquid exhaust gas was free of organic chlorine compounds.

Claims (3)

a short lifespan, especially if one does not rely on very special organic chlorine compounds, such as B. pure chlorobenzene, apply ^ 1. Process for the conversion of solid, liquid, but rather to the gaseous organic chlorine compounds occurring in practice or gaseous organic chlorine compounds, which in addition to fertilize with the formation of hydrogen chloride, d a-carbon, hydrogen and chlorine other elements, characterized by, that one contains such as oxygen and nitrogen, the partly organic: chlorine compounds at temperatures high-boiling, non-evaporable components contain of 300 bi, 1200 ^c C in the presence of a solid and their conversion into the gas phase based on the catalyst, the carbon or an element of the ίο Reason for polymerization and decomposition does not allow the third and / ν he fourth main group of the penode to be reached. systems in I ~ · <η of oxygen compounds. lasts, while avoiding elemental carbon and organic chlorine compounds, combustion and a gas containing hydrogen chloride in an incinerator or at sea (see decomposed. * 5 Chemical Engineering 79, No. 23 [1972] 54 D / H). here 2. Verfahr *, ι according to claim 1, characterized in that the organic chlorine compounds are countersigned because catalysts are used which were ^{burned by air and hydrogen at 1500 c} C, an inner surface (according to BET) of> 100 m ² / An extensive work-up follows, showing chlorine, recovering hydrogen , some of the chlorine 3. The method according to claim 1 and 2, characterized ao falls in the form of dilute alkali metal chloride solution, characterized in that catalysts are used which are discharged into the sea. containing silica and alumina. A disadvantage of this process is that the