DE1593437A1 - Selective hydrogenation - Google Patents

Description

"Selective Hydrogenation ' ¹

The invention relates to a method for selective hydrogenation and in particular to a method for selective hydrogenation Hydrogenation of acidic polymerizable material that Butadienes and ethyl acetylene in a C ^ hydrocarbons containing mineral oil stream.

It is known that in certain modern mineral oil raffinate ion process selected C ^ hydrocarbons Streams containing are conducted in alkylation units to convert unsaturated compounds into higher octane constituents to convert »However, there have long been some difficulties

0 0983 1/1 8 2Λ

Patent attorneys Dipl.-ing. Martin Licht, Dipl.-Wirtsdt.-Ing. Axel Hansmann, Dipl.-Phys. Sebastian Herrmann MÖNCHEN 2, THERESI ENSTRASSE 33 · Telephone: 292102 · Telegrarom address: lipatli / Mönchen

Bank details: Deufscha Bank AG, Filiole Munich, Dep.-Kane Viktualienmarkt, account number, 70/30538 Bayer. Verainsbqnic Munich, Zweigst, Oskar-von-Miller-Ring, account no. 882495 Postal check account: Mönchen No. 163397

ORIGINAL BATHROOM

associated with this alkylation process. In this Related normally produce thermal cracking processes and liquid coking processes, which are known for the production of different fractions (boiling ranges) of hydrocarbons are applied, streams containing substantial amounts of butadienes and ethyl acetylene along with isobutane, butylene, propylene and the like Connections included. When such streams are passed through conventional alkylation units using sulfuric acid are carried out, then the butadienes interfere and that

Acetylene the alkylation reaction by polymerization and dilution of substantial amounts of sulfuric acid,

Large losses of sulfuric acid in the alkylation process To prevent this, certain methods of pretreating the liquid flow with which the alkylation unit are to be used are to be used is charged, designed to remove the butadienes and ethyl acetylene. Be like that for example the butadienes selectively from the feed to the alkylation unit in a known process extracted. However, such a process is relatively uneconomical and time consuming. It was therefore very desirable to have a simple, quick and economical process to selectively remove butadienes and ethyl acetylene from the alkylation feed streams to develop. Such a procedure should - preferably the

1/1824

1593A37

Convert butadienes and ethylacetylenin products, which the quality of the alkylation feed streams and improve the quality of the product stream obtained from the alkylation units. Of course the process should not interfere with the other components of the alkylation feed stream.

The invention was based on the object> an improved one Process for the selective treatment of butadienes and ethyl acetylene in a C ^ hydrocarbons containing Developing stream in which the sulfuric acid requirement of the stream is reduced during the subsequent alkylation thereof will.

The invention relates to a method which is characterized in that acidic polymerizable material, containing butadienes, ethyl acetylene and mixtures thereof in a stream containing G hydrocarbons is selectively hydrogenated to mono-olefins. The current also contains mercaptan sulfur in a controlled manner Amount, however, is essentially free of inorganic, sulfur-containing catalyst poisons, including Carbonyl sulfide and hydrogen sulfide, a presulfided Nickel-based catalyst, which contains a high concentration of nickel sulfide, is used to facilitate the hydrogenation

the butadienes + any ethyl acetylene present + and

009831/1824 bad OBGiNal

At the.

to mono-olefins, even in the presence relatively less Concentrations of hydrogen to cause. By doing Process according to the invention is the catalyst, which is made on alumina or other resistant Base deposited nickel in an approximately optimal concentration, such as about 20 to 30 6ew,% Nickel, consists, first of all, of the oxidized state with hydrogen and hydrogen sulfide or others inorganic sulfur-bearing catalyst poisons are sulfided. The hydrogen converts the catalyst into an active form. The hydrogen sulfide reduces the Total activity of the catalyst for hydrogenation to a minimum, while maintaining the selectivity of it elevated. The catalyst is then equilibrated with the mercaptans in the feed stream, whereupon the total activity of the catalyst is adjusted to a satisfactory level, while the Hydrogenation selectivity of the catalyst is kept at a high level, so that the catalyst only the Hydrogenation of the easily hydrogenatable butadienes and ethyl acetylene can cause and not under the process conditions butylene, propylene and similar compounds hydrogenated. After the catalyst has been equilibrated with the mercaptans, these block Mercaptans change the activity and selectivity of the catalyst. during the conversion of the butadienes

009831/1824

and of ethyl acetylene, The conversion is carried out in one stationary layer with hydrogen and the C ^ hydrocarbons containing feed stream in the vapor state carried out at a suitable temperature and pressure. The desired transformation is achieved by a single passage of the current through the catalyst layer achieved,

The stream can then be passed through the alleyization zone and alkylated with maximum effectiveness be, there is a minimal consumption of sulfuric acid during the alkylation, ■

In the following, the process according to the invention is explained using an example acidic, hydrogen and hydrogen sulfide containing Sas is dureiigeleit through the catalyst with a throughput of 20.4 to 34.0 million m per day. The acidic gas contains 32.2 VoI,% Wasserstoffj '1.6 vol% hydrogen sulfide _e, the remainder consisting of methane ,, The catalyst is transferred from an inactive state to an active oscidierten, reduced state and at the same time to a pre-nickel sulfide

9 8 31/18 2 4 _BAD original

sulfided, which has a low overall activity and a high hydrogenation selectivity during the passage of the acidic gas through the catalyst layer. The catalyst is heated at a rate of about 66 ⁰ C per hour * If the catalyst layer temperature reaches about 204 ⁰ C, the flow rate of acid gas is m to about 40.7 to 47.6 million in those periods per day, and in this Throughput held until a positive test for hydrogen sulfide is obtained in the stream exiting the catalyst bed, i.e. in about 6 hours. The temperature of the catalyst layer is then increased to 260 ^° C. and held at this temperature until a positive test for hydrogen sulfide is obtained again, ie in about 4 additional hours. The presulfiding is then completed, after which the catalyst is cooled to 204-232 ⁰ C. During the presulfiding, the gas pressure in the system is about 7.03 kg / cm. After the presulfiding, the supply of acid gas is stopped and the pressure is allowed to drop to 0.3 kg / cm, whereby most of the sulfur-containing acid gas is removed from the system,

The remaining acidic gas is made with the help of pure or substantially pure hydrogen gas is removed from the catalyst layer. After that, the C. hydrocarbons

■■■ -. "-.. .Ti"

0098317 18 24 ''''^:;; - - '8AD

containing stream latalysatorschicht passed together with hydrogen through and increases the pressure of the system to 6.03 kg / cm vacuum "in the feed stream is the Tonzentration of butadiene at about 1 vol.%, the concentration of ethylacetylene at about 0.08 vol. #, The stream contains mixed C. hydrocarbons, mainly butyl-enes * with about 5% propylene, The addition of hydrogen is controlled so that one mole of hydrogen per mole of the acidic, polymerizable material (butadiene and ethyl acetylene) in the C. - Hydrocarbon stream is used. In addition, an additional excess of 3 moles of hydrogen, based on the total feed in the coming out of de "Keaktor gas _e This results in an addition of about 1, 98 to 2.83 m 0.16 m per hydrogen of C ^ -Kohlenwasserstoffbeschickungsstromes. Pure hydrogen is preferably used. However, for example, a hydrogen of 80-90% purity can also be used, but with corresponding changes in the gas flow rate, etc. ppm. The inlet temperature to the reactor zone is set at 204 ° C. The eutadiene content of the stream containing C. Koklenvap® and exiting the reactor zone is checked. The temperature of the incoming C. hydrocarbon stream will then be like this

'BAD GkIGsWAL 009 83 1/18 2'

set that the butadiene content in the outgoing stream is less than 50 ppm. The outermost temperature obtained in the reactor layer is 232 ^° C. The process according to the invention can be continued for β months. The product stream consistently shows a zero concentration of ethyl acetylene and less than 50 ppm. Butadiene. The process according to the invention is suitable for an alkylation with a minimal consumption of sulfuric acid.

The other advantages of the method according to the invention verden further explained in detail on the basis of the drawings:

The drawing represents a schematic flow diagram a system that for the selective hydrogenation of butadiene and ethyl acetylene to mono-olefins in one C. hydrocarbon containing stream is used.

The one used for hydrogen carbonate alkylation Feed material usually consists mainly of mono-olefins, such as butylenes, but can also butane, isobutane, propane and an amount of propylene usually no more than about 20 vol Sfc contain. The feed material also contains one

009831/1824 BAOORSGMAt

appreciable amount of butadienes, be present, for example up to about 3 wt,%, it can also be a small amount of ethyl acetyl s (for example. 0.08%). Higher concentrations of butadienes and / or ethyl acetylene are also expected, although these are rare. The feed material also contains mercaptans in a concentration of not less than 0.065 g per 2.83 m, and preferably about 1.95 to 2.28 g per 2.83 m. Normally the mercaptan content is not higher than about 3.25 g per 2.83 m. The content of inorganic] sulfur-bearing catalyst poison, ie the combined content of carbonyl sulfide and hydrogen sulfide should preferably be zero, in any case be kept at a value that is lower than

3
0.0-65 g per 2.83 m. Typically, the level of this catalyst poison will not exceed about 50 ppm.

The feed material described above is introduced into the heat exchanger ΐ6 in a stream through the supply line 10, on which a pump 12 and a valve 14 are arranged. The complaint! Coverage stream comes in an indirect heat exchange with a stream coming out of the hydrogenation reactor 18. The hydrogenation reactor 18 "operates in a temperature range from about 149 to stw & 288 ⁰ C. Higher and lower reactor

"- -; BADORiC ^{1 TIME}

009831/1824.

- ίο -

temperatures are possible, but seldom and not necessary. Essentially pure hydrogen that does not contain any significant amounts of an inorganic, sulfur-bearing nickel catalyst poison contains, is through the supply line 20, through the valve 22 and through the line 1O in the Heat exchanger 16 passed where it meets the feed stream mixes. The hydrogen is preferably pure, but can also not be pure, for example in an 80 to 95% concentration, the hydrogen should be essentially free of impurities

(except mercaptan), which poison the catalyst. Therefore, the inorganic, sulfur-bearing nickel catalyst poison content, i.e. the content of H ₃ S and COS, in the hydrogen stream is kept low, if possible below 0.065 g per 2.83 m and preferably close to a zero value. ·

The feed stream and the hydrogen are, for example, heated in the heat exchanger 1 6, euf a temperature of about 80 ^G C. The temperature can, of course, depending on the size of the heat exchanger, and so the temperature of coming out of the reactor stream _o vary considerably. The feed stream and hydrogen are passed through the heat exchanger at an appropriate flow rate.

00 983 1/1824 bad ORIGINAL

conducts, for example in an amount of about 1 / 58.8 mill. m per day and under a suitable pressure which - at ambient pressure up to 10.5 - T4.1 kg / cm or more, for example at about 12.0 kg / cm. The feed stream and hydrogen are then passed through lines 24 and 27 into and through steam heated evaporator 28, then passed through line 32 to heater 30. In the evaporator 28 and in the heater 30, which is heated with the aid of gas or other fuels supplied through the line 34 and the valve 36, the temperature of the feed stream and the hydrogen is brought to the desired reaction temperature, ie to a temperature which is from 177 to about 288 ° C, for example at about 204 ⁰ C. Normally the vaporizer is left out after the uranium conversion reaction has started.

The feed stream and hydrogen are then passed through line 38 to the top of reactor 18 which contains a stationary layer of the catalyst. The reactor operates at a catalyst bed ^{temperature of about 1 77 to 288 °} C. or similar temperatures and under pressures which are from ambient pressure to 13.1 kg / cm negative pressure or more. For example

2 becomes an inlet pressure of about 10.2 kg / cm negative pressure and a

2
Outlet pressure of about 9.5 kg / cm vacuum was used.

0 0 9-8 31/182 A. bad örjg ^ äL

During the start-up of the reactor the temperature of the catalyst layer at a rate of about 66 ⁰ C per hour until the reaction temperature increases, the preheated feed stream and / or hydrogen are used. After the conversion reaction has started, the reactor bed temperature is controlled within the desired range by the flow rates of the feed stream and the hydrogen and by the preheating stages. The reactor 18, the evaporator 28, the heat exchanger 16, the heater 30 and the entire equipment including the lines, pumps and valves, as described and shown in the drawing, can be of the usual size, shape and construction.

The reactor 18 contains a stationary layer suitable catalyst made on an inert basis applied nickel. The nickel content should at least about 18%, preferably 20-23%.

The catalyst is on an inert basis such as alumina, silica or a Mixture of both applied. The catalyst is in front Use reduced for activation and almost completely presulphided to nickel sulphide. The nickel content of the Catalyst should be at least 18 wt.% Since

009831/1824

BAD OR

lower concentrations severely limit the amount of inorganic, sulfur-bearing catalyst poison allowed in the feed stream. Preferably, no such catalyst poison should be present. However, most Beschickungsströrae for the alkylation include sufficient amounts of such poisons in order to inactivate the catalyst within a relatively short period of time _v, if the nickel content is not, at least about 18 wt,%, preferably about 23 wt.% Or more. The catalyst is in the stationary bed, preferably of a fine grain size that allows easy passage of the C 1 -C hydrocarbon-containing alkylation feed stream and hydrogen and good contact with the catalyst.

In the case of a characteristic presulfiding, the catalyst is used in the reactor 18 in the form of a stationary phase. An acid gas containing hydrogen and hydrogen sulfide in a suitable concentration includes, for example, about 10-40% by volume of hydrogen and about 1 -..% Hydrogen sulfide in methane or a similar material 10 by volume, is passed through line 20, valve d m? ₂ 2, the line 1O, the heat exchanger 16, the lines 24 and 26, the evaporator 28, the line 32, the heater 30 and the line 38

009831/1824

a suitable pressure, for example 6.03 kg / cm under pressure and at a suitable temperature such as 66 ° C in the reactor 18 introduced. The hydrogen sulfide is also in the absence of hydrogen for the presulfiding and also with

about 204 C for the reduction and presulfiding effective. Consequently, a hydrogen-free, hydrogen sulfide can also be used containing gas can be used, for example other inorganic, sulfur-bearing nickel catalyst poisons such as COS.

The temperature of the acid gas is increased to a certain degree, for example at 66 ° C. per hour. The catalyst is heated to about the same degree with the aid of the acid gas. The flow rate of the acid

Gas is initially about 14.2 to 34.0 million cubic meters per day, but is usually increased to about 39 6 to 48.1 million m \ ro day when the catalyst layer temperature reaches about 204 ⁰ C. The catalyst bed temperature is then normally maintained at about 204 ^° C. until hydrogen sulfide is detected in the stream exiting the reactor. This occurs after about 5-7 hours. The temperature of the catalyst layer is then increased to between 260 and 288 ° C. and held at this temperature until a positive hydrogen sulfide test is again obtained, usually after about 3-5

009831/1824

additional hours. The catalyst bed temperature is controlled at all times by heating the acidic gas to the desired temperature. Pre-sulphidation and reduction can be carried out with hydrogen sulphide or with hydrogen sulphide and Hydrogen can be carried out using comparable time-temperature ratios.

The purpose of presulfiding is to minimize the overall activity of the reduced catalyst while maximizing the selectivity of the catalyst for hydrogenation of the readily hydrogenatable butadienes and ethyl acetylene (without hydrogenation of the mono-olefins in the feed stream). However, after the vasulfidation, the total activity of the catalyst must be increased enough to allow the reaction to proceed relatively quickly. This is achieved according to the invention in that the presulfided catalyst with at least 0.065 g of mercaptan sulfur per 2.83 m ^{3 of} feed stream and preferably with 1.95 to 2.28 g of mercaptan sulfur per 2.83 nr of the feed stream during the conversion of the butadienes and the ethyl acetylene into Balance is brought about. The particular concentration of mercaptan sulfur varies with the feed stream. Usually 0.065-0.32 5 g is sufficient

• 3

Mercaptan sulfur per 2.83 m feed stream, 009831/1824

During the partial stripping of the hydrogen sulfide is prior to being fully equilibrated with the mercaptan sulfur, causing the reaction to proceed allowing hydrogenation at a sufficient rate, sufficient activity of the catalyst restored. The equilibrium is obtained after the mercaptan-containing product described has passed through Feed stream and hydrogen through the reactor layer at reaction temperature during one Period from a few hours to a day or a similar period of time depending on the reaction temperature etc. depends. After equilibrium has been established, the mercaptan sulfur blocks further removal of hydrogen sulfide from the catalyst, so that a high hydrogenation selectivity together with a satisfactory Catalyst activity is maintained, since the mercaptan sulfur does not react with the catalyst, the equilibrium is essentially maintained throughout the process.

It is necessary to prevent more than 0.065g at most, preferably not more than a few parts per million of an inorganic, sulfur-bearing catalyst poison, such as hydrogen sulfide, each 2.83 nr feed stream is present. Higher Concentrations resulfide the catalyst and are sufficient

009831/1824

off, its activity at about the low, presulphided Reduce level, keeping the rate and effectiveness of the hydrogenation reaction at the desired level The reaction temperature is hindered. Preferably no or almost no hydrogen hydrogen or other inorganic sulfur-bearing poisons in the feed stream to be available.

After completion of the Vörsulfidierung allowed the catalyst to about 204 ⁰ C to cool and the supply of acid gas is interrupted with the aid of the valve 22nd The pressure of the system is allowed to drop to a low level, for example 0.3 kg / cm. The system is then made hydrogen sulfide free by bubbling hydrogen through the system for a few minutes. The pressure in the system is then gradually brought to a pressure of 6.03 kg / cm negative pressure, for example, and the feed stream is passed through the reactor together with the hydrogen.

In the reactor, the acidic, polymerizable material, containing butadiene and / or ethyl acetylene, at the desired transition temperature of 177-288 ° C or at similar temperatures substantially completely hydrogenated to the corresponding butylenes without a substantial

009831/1824

Hydrogenation of the mono-olefins in the feed stream takes place. In this regard, the appropriate process conditions including temperature and the flow rate adjusted so that the concentration of butadienes and ethyl acetylene in the reactor leaving stream is less than about two parts per thousand, preferably not more than about 50 ppm. A Passage of the feed stream in vapor form through the reactor is sufficient to achieve the desired conversion.

After the conversion, ie the selective hydrogenation, has been carried out continuously for a period of about 6 months, a sufficient amount of carbonaceous deposits is formed on the catalyst, as a result of which a higher operating temperature within the range described is required. Shortly thereafter, the catalyst must be regenerated using conventional steam or air treatment. For example, the steam necessary for the regeneration of the catalyst can be carried through the cleaned system at about 1,81,272 kg per hour. The temperature of the catalyst layer is about 66 ⁰ C per hour to 371 - 399 ° G increases. When an oil-free effluent is obtained, 1-5% by volume of air is added to the steam, the temperature of the bed being set below 482 ° C.

009831/1824

If the COg content of the effluent falls below 2% , the reactor is cooled with steam to less than 204 ° C,

The stream exiting reactor 18 during the selective hydrogenation reaction is passed through line 40 to the indirect heat exchange with the feed stream and the hydrogen in heat exchange 16. After heat exchange, the temperature drops of the current of about 80 ⁰ C to about 52 ° C and the pressure decreases for example from about 11.3 to l3,1 kg / cm under pressure to about 9.2 kg / cm under pressure. The stream is then passed from heat exchanger 16 through line 42 into one or more cooling devices 44. Two cooling devices connected in series are preferably used. The cooling devices are cooled by indirect heat exchange with cooling water which is conducted into and out of the cooling device with the aid of lines 46 and 48. During this heat exchange, the temperature of the stream drops, for example, to about 43 ° C. and the pressure, for example, to about 8.84 kg / cm negative pressure. From the cooling devices 44, the flow is passed through line 50 into a drum-shaped container 52, in which it is stored and from which it is passed to the alkylation unit and to other devices not shown here.

009831/1824

For example, in a continuous selective hydrogenation employing about 1,360 kg catalyst bed, about 158.8 million m³ of liquid olefinic material was removed from the coolers per day for a six month period at a pressure of about 8.14 kg / cm vacuum along with about 5.915 million m3 of a gaseous material continuously obtained. The gaseous material was suitable for transfer to a fuel gas drum. During the test period the butadiene content of the stream exiting the reactor averaged no more than about two parts per thousand and the ethyl acetylene content could be neglected. The butadiene content of the feed stream prior to selective hydrogenation averaged 2 percent by volume and the ethyl acetylene content averaged about 0.8 percent by volume . No conversion of the mono-olefins could be detected during the test period. The process of the invention could be carried out in full effectiveness during the test period and no regeneration of the catalyst was necessary during this period. The following table shows some typical process conditions for a selective hydrogenation reaction.

009831/1824

TABEL

Temperature of the feed stream at the heater

Temperature of the feed stream at the reactor inlet

Catalyst bed temperature 66 cm below the top of the bed

Catalyst bed temperature 127 cm below the top of the bed

Catalyst bed temperature 1,88 cm below the top of the bed

Catalyst bed temperature 249 cm below the top of the bed

Catalyst bed temperature 310 cm under the top of the layer

Temperature at reactor outlet

Hydrogen flow rate

Rate of flow of the feed stream to the reactor

Product Recovery Rate Reactor Inlet Pressure

79 ° C m ³ / day 199 ° C m ³ / day 195 ° C m ³ / day 1 99 ° C , 16 kg / cm ²
negative pressure 202 ° C 206 ⁰ C 208 ⁰ C 202 ⁰ C -4.44 ° ( 2 , 954 million 174 , 68 mill. 170 , 55 mill. 25th

The method according to the invention is therefore a simple, economical and effective method for Removal of butadienes and ethyl acetylene from mono-olefins containing alkylation feed streams in which essentially and selectively only the butadienes and that

009831/1824

Verden ethyl acetylene hydrogenated to mono-olefins. The after materials treated with the process of the invention give excellent feed streams for alkylation, those with a very low consumption of sulfuric acid alkylated can verden. The conversion reaction, i. the selective hydrogenation can be carried out continuously for long periods of time without any Regeneration of the catalytic converter or frequent changes to the control conditions become necessary. The reaction runs at moderate temperatures and at a suitable

Print off, with a presulphided, high nickel content The catalyst used has a high selectivity for the triply saturated aliphatic Compounds, especially for the butadienes and the ethylacetyls ^ Ln owns the feed stream. This selectivity It is used in the presence of active quantities of mercaptans and in the almost complete absence of inorganic, sulfur-bearing substances Nickel catalyst poisons such as Hydrogen sulfide, maintained. The method does not require complicated apparatus or equipment special maintenance. It is therefore a very economical process.

The various stages of the method according to the invention, the parameters and those for carrying out the Process according to the invention necessary devices

009831/1824

- 23 -

can of course be modified in many directions.

003831/1824

Claims (9)

Patent application; "Selective hydrogenation" claims 1. A method for reducing the consumption of sulfuric acid in an alkylation feed stream containing C. hydrocarbons, characterized in that an acidic, polymerizable material containing butadienes, ethyl acetylene or mixtures thereof in a C. hydrocarbons containing stream in an Eeaktionszone without hydrogenation of the in mono-olefins present in the stream are selectively hydrogenated, the feed stream and hydrogen in the vapor state at approximately 149-288 ° C with a tough base, presulphided, high nickel content catalyst in the presence of at least 009831/1824 is about 0.065 g of mercaptan per 2.83 m of feed stream and in the almost complete absence of inorganic, sulfur-bearing nickel catalyst poisons, is brought into contact until the content of acidic, polymerizable material in the feed stream in the is substantially reduced, and then recovered the reaction product from the reaction zone and the Alkylation is supplied, 2, The method of claim 1, characterized in that the nickel catalyst comprises at least about 1 8 wt.% Of nickel sulfide, and the total concentration of the inorganic sulfur-bearing nickel catalyst poison including the hydrogen sulfide in the reaction zone under 0,065 g per 2.83 m of the feed stream is maintained. 3. Process according to Claims 1 and 2, characterized in that the mercaptan content is between approximately q
0.065 g and about 3.25 g per 2.83 m of the feed stream is located, wherein the nickel sulphide content of the catalyst is between about 18 and about 23 wt% by weight., And wherein the molar concentration of hydrogen in the reaction zone in an excess of at least about 3 Mole over the mole concentration of the acidic polymerizable material is present in the reaction zone. 009831 / 182A 4. Process according to Claims 1-3, characterized in that the selective hydrogenation in a gaseous state under elevated pressure and at a temperature between about 204 and about 288 ° C is carried out. 5. Process according to Claims 1-4, characterized in that the total content of hydrogen sulfide in the feed stream and in the hydrogen is substantially zero and the mercaptan content in the reaction zone between about 0.325 g and about 2.28 g per 2.83 m of the feed stream held 6, process according to claims 1-5, characterized in that the selective hydrogenation is continuous is carried out over a longer period of time and the total concentration of the acidic, polymerizable material in the stream exiting the reaction zone is maintained at no more than about two parts per thousand. 7, method according to claims 1-6, characterized in, that the total concentration of acidic polymerizable material in that from the reaction zone outgoing current does not exceed 50 parts per million 009831/1824 bad original 8. The method according to claims 1-7, characterized in that the catalyst is almost completely presulphided before the selective hydrogenation by being brought into contact with an inorganic, sulfur-bearing catalyst poison at at least about 204 ° C and the presulphiding temperature then to about 288 ⁰ C is increased and contact with the poison is maintained until presulfiding is essentially complete. 9. The method according to claims 1-8, characterized in that during the presulphiding hydrogen sulphide is ended as a catalyst poison, the catalyst is reduced at the same time by contact with hydrogen from an oxidized state, the catalyst during the presulphiding at a rate of no more heated vird than about 66 ° C per hour to about 204 ⁰ C, vird maintained at this temperature until Schvefelvasserstoff in the coming out of the reactor stream is present. then not as etva 66 ° C per hour in the Gegenvart of hydrogen and Schwefelvasserstoff heated vird, the latter temperature vird maintained until viederum Scnvefelvasserstoff in the coming out of etva 204 ⁰ C on etva 288 ° C at a rate of more from the reactor Current is detected and the reactor BATH 009831/1824 is then cooled to about 149 to 204 ⁰ C, whereupon the selective hydrogenation is started. 10 _# Process according to claims 1-9, characterized in that the process is carried out continuously by periodically interrupting the selective hydrogenation, regenerating the catalyst and then repeating the presulfiding and the subsequent selective hydrogenation, 11, method according to claims 1 -10, characterized in that the resistant base consists of Alumina, silica, or mixtures thereof, the catalyst is presulphided with hydrogen sulphide is effected and the hydrogen sulfide is removed from the catalyst after the presulfiding, which selective hydrogenation is carried out in the absence of carbonyl sulfide and hydrogen sulfide and that acidic, polymerizable material made from butadiene and ethyl acetylene consists. 009831/1824 ORIGlNAL BATHROOM