Field of the Invension

The present invention relates to catalysts on inorganic carriers expressed in following general formular (I) which is required to produce lower hydrocarbon(s) contsώ ng C2 having mainly double bond such as ethylene used as a basic active chemical compound in the field of petrochemical industry and fine chemical industries such as pharmaceuticals .agrochemicals, etc. including polymerization, copolymerization and polycondensation reaction by converting directly lower hydrocarbon(s) containing CI to C4 hydrocarbon(s) such as methane, purified natural gas (hereinafter, LNG) and liquefied petroleum gas (hereinafter, LPG) and process for preparing thereof.

Ma c / S formular ( I )

Further, the present invention is to provide a new process for converting (preparing) directly lower hydrocarbon(s) containing CI to CA such as methane or LNG at the temperature of about 500 to 980 °C, preferably in the range of 670 to 850 °C, which is distinctly lower reaction temperature relative to that of conventional synthesis of hydrccarbon(s) by dehydrogenation as similar prior art using the same catalyst but being different tx_cr-nical field of present invention, with nitrogen in the presence of same catalyst, wherein, with high yield hardly obtainable till now, lower olefinic hydrocarbon(s) containing C2 such as ethylene which is active chemical compounds for basic reaction is obtained by simple process

in short time and almost no by-product such as CO ₂ obtained in the reaction such as oxidative coupling reaction conducted by introducing oxygen .

In Ma'Pc / S of above mentioned general formular ( I ), M is a compound selected from the group of RuCb PPhsk RuC_2(CO)2(PPh3)2,

Ru3 ⁽ CO)i2. RhCl(CO)(PPh3)2. IrCKCOXPPhs PdtPPha PtGPPtok RuCls ^" xH ₂ O, S is a inorganic carrier selected from C.-AI2O3, Υ-.AI2O3, SiO ₂ , S AbO Y-zeolite, MgO and TiO ₂ , P is a phosphorus compound as

promoter selected from PPha, P OCIfe P C Hsk P(O)(OC2H5)3, a' is

weight percentage of metal in catalyst, selected appropriately within the range of 0.25 to 5 wt %, c is weight percentage of promoter in catalyst, ranging from 1.0 to 20.0 wt %. Background .Art

It is well known that, as prior art, few number of literatures and patents about the catalyst can produce ethylene by direct conversion of methane is disclosed; it is different technical field of present invention and has such disadvantages producing large amount of by-product such as carbon dioxide that separation and removal is difficult, and environmental pollution is likely to be caused; and synthesis of hydrocarbon(s) by conventional dehydrogenation is conducted at relatively high temperature of about 1500 to 1550 °C by thermal or electric cracking reaction to cause some problem such as enormous loss of supply of high energy, expense of high temperatured equipment (plan) as well as thermal energy expense , particulary severe corrosion of reactor thereby. As prior art about synthesis of hydrocarbon by oxidative coupling

and dehydrogenation reaction, there are U.S patent nos. 5066629, 5068486 and 5118654, Canadian patent no. 2016675 and Japanese patent nos. 04352730, 04368342. Summary of the Invention Therefore, in the present invention, due to prepare lower hydrocarbon such as ethylene by direct conversion of methane or LNG free from such above mentioned problems in the presence of new catalyst of present invention without any by-product such as CO2 of oxidative coupling reaction, new catalyst able to conduct conversion reaction not at so (ultra) high temperature of process of synthesis of hydrocarbons by dehydrogenation but at distinctly lower (midlow) temperature, necessity of new process for producing this catalyst and new process for conversion (preparation) into lower hydrocarbon(s) such ethylene using this new catalyst have always been expected. To meet the expectations above, after years of study, the inventors of this invention cleared of various defects that had been mentioned above and achieved complete development of a new catalyst and preparation thereof, which is a simple process for obtaining lower olefinic hydrocarbon(s) containing C2 to C4 such as ethylene with high yield and trace amounts of impurities in the presence of present catalyst within short time by direct conversion of lower hydrocarbon suh as methane or LNG at distinctly lower reaction temperature compared to process of synthesis reaction of hydrocarbon by dehydrogenation or oxidative coupling reaction ; thus direct conversion lower hydrocarbon(s) such as methane, etc. being carried out at distinctly lower temperature cause to save enormous amount of heat energy cost that were needed in synthesis reaction of

hydrocarbon(s) by dehydrogenation or oxidative coupling reaction, furthermore provide a process for preparing of new catalyst sufficiently efficient to environmental pollution problems through definately reducing trace amounts of impurities, namely CO2, at the same time convert lower hydrocarbon(s) containing C2 to C4 such as methane or LNG into lower olefinic hydrocarbon(s) containing C2 to C4 such as ethylene, within short period, with surprising efficency of high yield. Detailed Description of the Invention

The present invention will be described in furtherdetail with reference to Examples.

First, to produce new desirable catalyst, supported catalyst for production of lower hydrocarbon(s) having C2 to C4 in double bond, mainly ethylene, is produced by supporting metal complex with promoter on inorganic carrier, thus trying to directly produce lower hydrocarbon(s) such as ethylene by dehydrogenation coupling reaction of methane or LNG , catalyst active for producing lower hyclrocarbon(s) containing C2 to C4 having mainly double bond such as ethylene is produced by supporting various organic metal complex and promoter on inorganic carrier.

In this method, process of synthesis and purification is much easier than other preparations.

Through development of this catalyst, reaction conditions such as reaction temperature, reaction pressure are mitigated considerably to lower state and lower hydrocarbon(s) such as ethylene are produced with high yield. Further, due to development of process through catalyst of the present invention, productivity is enhanced greatly by simplif ying the

preparation of lower hydrocarbon(s) such as ethylene.

Detailed explanation of present invention are as follows. In the present invention, by developing a new process where direct converting lower hydrocarbon(s) such as methane or LNG into lower hydrocarbon(s) having C2 to C4 in double bond, mainly ethylene, which is the main technical difference from existing synthesis reaction of hydrocarbon by dehydrogenation or oxidative coupling reaction, overall process is simplified, further, reaction temperature is declined to a temperature of about 500 to 980 °C, prefarably in the range of 670 to 850 °C, and amounts of impurities such as carbon dioxide are greatly reduced.

In the present invention, in producing lower hydrocarbon(s) such as ethylene, ethylene is produced using catalysts : Ru complex such as RuCl ₂ (PPh3) ₃ , RuCb(CO) ₂ (PPh3) ₂ , with adding triphenylphospine with high yield at the temperature of about 810 °C, at this time conversion ratio is maintained in the range of about 8 to 12 and almost all the raw material introduced (about 93-100%) are converted through recirculation.

That is to say, reaction condition such as reaction temerature and pressure are enormously mitigated through solid surface reaction using supported catalyst of Ru complex series, at the same time simplification of reaction equipment is reached.

Process for preparing supported catalyst on inorganic carriers in the present invention is as follows.

Metal cluster (compound) and organic metal complex are dissolved in mixture solvent consisting of mainly dichloromethane and acetone. Furthermore, inorganic carrier is added to this solution, and catalyst substance is dipped into inorganic carrier about 20 to 200 "C, then

catalyst is prepared by being dried in vaCTimm drier.

Inorganic carriers used here are α-AfeO Υ-.AI2O3, SiO ₂₎ Siθ2-A-2θa Y-zeolite, MgO and ΗO2 .

And catalyst compounds used are RuCb PPhsk RuCMCOMPPhs Ru ⁽ CO)i2, RhCl(CO)(PPh3) ₂ . IrCl(CO)(PPh3) ₂ , Pd ⁽ PPh3) ₄ . PtfFPha ⁾ -.. RuCls xH ₂ O.

According to the experiments of the present invention, the ideal inorganic carrier for preparation of lower hydrocarbon(s) such as ethylene are C.-AI2O3 and MgO, and metal of VI series is Ru, Rh. Reaction conditions in the presence of new catalyst in the present invention are as follows.

For example, dilution ratio of nitrogen to methane or LNG is 1 to 6, preferably 1 to 3.

Reaction temperature is about 500 to 980 °C, preferably in the range of 670 to 850 °C, most preferably in the range of 710 to 810°C.

Concentration of catalyst is below 5 wt %, preferably 1 to 3 wt %.

Space velocity of source gas is about 75 to 1200 hr ^"1 , prefarably in the range of 150 to 600 hr ^"1 .

Reaction pressure is usually about 1 to 10 arm, preferably in the range of 1 to 5 atm.

Conversion ratio of lower hydrocarbon(s) containing CI to C4 such as methane or LNG of the present invention and yield and selectivity of lower olefinic hydrocarbon(s) containing C2 to C4 such as ethylene are defined as follows.

mol numbers of methane reacted conversion ratio (mol %) = x 100 mol numbers of methane supplied

mol numbers of lower hydrocarbon compound such as ethylene produced yield (mol %) = x 100 mol numbers of methane supplied

mol numbers of lower hydrocarbon compound such as ethylene produced selectivity(mol %) = x 100 mol numbers of methane reacted

or,

mol numbers of LNG reacted conversion ratio (mol %) = x 100 mol numbers of LNG supplied

mol numbers of lower hydrocarbon compound such as ethylene produced yield (mol %) = x 100 mol numbers of natural gas supplied

mol numbers of lower hydrocarbon compound such as ethylene produced selectivity(mol %) = x 100 mol numbers of natural gas reacted

Reactant and product are analyzed by Gas chromatograph. From example 1 to 11, there are descriptions of new catalyst and process for producing new catalyst, from exmaples 12 to 22, there are descriptions of new process for producing lower hydrocarbons having C2 to C4 mainly in double bond by conversion reaction of lower hydrocarbon(s) containing CI to C4 such as methane or LNG in the presence of new catalyst (formular (I) ). EXAMPLE 1

α-Al ₂ O ₃ 5.16g, RuCl ₂ (PPh3) ₃ l.OOg (1.04 mmol), PPhs

1.09g(4.16mmol) are added to mixture solvent consisting of 20 ml of dichloromethane and 10 ml of acetone and stirred up about 30 minutes at the temperature of around 40 °C. This suspension is vaporized and solidified by distillation under reduced pressure, then dried in vacuum drier about 20 hours to prepare RuCMPPhs PPhs/ α-Al ₂ O ₃ catalyst EXAMPLE 2

RuCl ₂ (CO)2(PPh3) ₂ 0. 56 g (0. 744 mmol), PPhs 0.78g(2.97mmol) is added to mixture solvent consisting of 40 ml of dichloromethane and 10 ml of acetone and dossolved, then C.-AI2O3 3.68 g is added. This suspension is stirred up about 30 minutes at the temperature of around 40 °C and solvent is distilled under reduced pressure. Then dried in

vacuum drier about 20 hours to prepare RuCl ₂ (CO) ₂ (PPh ₃ )2. PPh ₃ / α-Al ₂ O ₃ catalyst.

EXAMPLE 3

C.-AI2O3 3.95g, Rua(CO)i2 0. 17 g (0. 266 mmol), FFfe 0.09g (0.343mmol) are added to mixture solvent consisting of 10 ml of dichloromethane and 100 ml of acetone and dissolved.

This suspension is stirred up about 30 minutes at the temperature of around 40 °C and solvent is volitized by distillation under reduced pressure. Residue obtained is dried in vacuum drier about 20 hours to prepare

Ru ₃ (CO)i2.PPh3 / C.-AI2O3 catalyst.

EXAMPLE 4

C.-AI2O3 3.28g, RhCl(CO)(PPh3) ₂ 0. 45 g (0. 652 mmol) PPhs 0.68g (2.59mmol) are added to mixture solvent consisting of 10 ml of dichloromethane and 30 ml of acetone and dissolved.

This suspension is stirred up about 30 minutes at the temperature of around 40 °C and solvent is volitized by distillation under reduced pressure.

Residue obtained is dried in vacuum drier about 20 hours to prepare RhCKCO)(PPh3)_.PPh3 / α-Al ₂ O ₃ catalyst.

EXAMPLE 5

C.-AI2O3 3.14g, IrCl(CO)(PPh3)2 0. 26 g (0. 333 mmol), PPha 0.35g (1.33mmol) are added to mixture solvent consisting of 60 ml of dichloromethane and 10 ml of acetone and dissolved. This suspension is stirred up about 30 minutes at the temperature of around 40 °C and solvent is volitized by distillation under reduced

pressure.

Residue obtained is dried in vacuum drier about 20 hours to prepare IrCl(CO)(PPh3)2 PPfo / α-Al ₂ O ₃ catalyst.

EXAMPLE 6 C.-AI2O3 3.7 g, Pd(PPh3) ₄ 0. 84 g (0. 727 mmol) PPhs 0.76g

(2.90mmol) are added to mixture solvent consisting of 30 ml of dichloromethane and 10 ml of acetone and dissolved.

This suspension is stirred up about 30 minutes at the temperature of around 40 °C and solvent is volitized by distillation under reduced pressure.

Residue obtained is dried in vacuum drier about 20 hours to prepare Pd(PPh3)4PPh3 / C.-AI2O3 catalyst.

EXAMPLE 7 α-Al ₂ O ₃ 4.45 g, Pt(PPh ₃ ) ₄ 0. 58 g (0. 466 mmol), PPI 3 0.49 g (1.87 mmol) are added to mixture solvent consisting of 30 ml of dichloromethane and 10 ml of acetone and dissolved.

This suspension is stirred up about 30 minutes at the temperature of around 40 °C and solvent is vaporized by distillation under reduced pressure. Residue obtained is dried in vacuum drier about 20 hours to prepare

Pt(PPh ₃ ) ₄ • PPhs / α-AbOa catalyst.

EXAMPLE 8

Except using MgO 4.39 g and PPI13 0.93g(3.55mmol)as inorganic carriers, same method of example 1 is used to prepare RuCl2(PPh3)3.PPh3 / MgO catalyst.

EXAMPLE 9

Except using RuCMPPhs^ 0.25g (0.261mmol, 0.5wt% Ru) and PPhs 0.27g(1.03mmol) as inorganic carriers, same method of example 1 is used to prepare RuC^PPl^sPPhs / α-Al ₂ O ₃ catalyst. EXAMPLE 10

Except using RuC^PPlis^ 1.0g(1.04mmol, 4.0wt% Ru) and PPhs 1.09g (4.16mmol) as inorganic carriers, same method of example 1 is used to prepare RuC^PPhs PPhs / α-Al ₂ O ₃ catalyst.

EXAMPLE 11

C.-AI2O3 5.01 S, RuCls ^• xH ₂ O 0. 21 g (1. 012 mmol), PPhs 1.06g

(4.04mmol) are added to mixture solvent consisting of 20 ml of dichloromethane and 10 ml of acetone and stirred up about 30 minutes at the temperature of around 40 °C. This suspension is vaporized and solidified by distillation under reduced pressure, then dried in vacuum drier about 20 hours to prepare RuC-3 ' xH_ ' PPI13 / CI-AI2Q3 catalyst

The results of analysis given in the following table from Examples 12 to 22 are approximate values.

And in case of temperatures, they are surrounding temperatures based on given value. EXAMPLE 12

Methane ( or LNG ) and nitrogen are added each at the flow rate of 10 ml/min in continuous stationary phase flow reactor (inner diameter: 0. 70 cm, length: 40 cm, stuff: stainless steel 316) under the catalyst RuCl2(PPh3)3PPh3 / α-Al2θ ₃ (2 wt% Ru) prepared example 1, product by continuous reaction under around 1 atm ( to 5 atm ) at each reaction

surrounding temperature is obtained and the result of analysis by gas chromatography is as following Table 1 (hereinafter example 12, law material is continuously reintroduced to conversion reaction).

Table 1

Reaction

Conversion Yield {%) Selectivity (%) Temp. %

*CC) Ethylene Ethane Ethylene Ethane

710 2.2 1.4 0.8 63.6 36.4 730 3.6 2.5 1.1 69.4 30.6 750 4.9 3.9 1.0 79.6 20.4 770 6.0 5.3 0.7 88.3 11.7 790 8.6 7.7 0.9 89.5 10.5 810 12.1 11.0 1.1 90.9 9.1

EXAMPLE 13

Except using RuCl2(CO) ₂ (PPh3)2 ^' PPhs / α-Al ₂ O ₃ as catalyst, same method of example 12 is used and the distribution of resultant product is as following Table 2.

Table 2

Reaction

Conversion Yield (%) Selectivity (%) Temp. % *CC) Ethylene Ethane Ethylene Ethane

710 2.8 1.9 0.9 67.9 32.1 730 3.8 3.0 0.8 78.9 21.1 750 4.6 4.0 0.6 87.0 13.0 770 5.4 4.8 0.6 88.9 11.1 790 6.6 5.9 0.7 89.4 10.6 810 8.6 7.7 0.9 89.5 10.5

EXAMPLE 14

Except using Ru3(CO)ι ₂ ^■ PPI13 / α-Al ₂ O ₃ ( 2 wt % Ru ) as

catalyst, same method of example 12 is used and the distribution of resultant product is as following Table 3.

Table 3

Reaction

Conversion Yield (%) Selectivity {%) Temp. % *CC) Ethylene Ethane Ethylene Ethane

710 2.4 1.7 0.7 70.8 29.2 730 3.5 2.9 0.6 82.9 17.1 750 4.6 4.0 0.6 87.0 13.0 770 5.4 4.8 0.6 88.9 11.1 790 6.8 6.2 0.6 91.2 8.8 810 8.3 7.8 0.5 94.0 6.0

EXAMPLE 15

Except using RhCl(CO)(PPh3) ₂ ^" PPha / α-AkOs (2wt% Rh) as catalyst, same method of example 12 is used and the distribution of resultant product is as following Table 4.

Table 4

Reaction

Conversion Temp. Yield {%) Selectivity (96)

*rc) %

Ethylene Ethane Ethylene Ethane

710 2.2 1.2 1.0 . 54.5 45.5 730 2.6 1.8 0.8 69.2 30.8 750 4.4 3.4 1.0 77.3 22.7 770 5.5 4.7 0.8 85.5 14.5 790 6.7 6.0 0.7 89.6 10.4 810 8.5 7.8 0.7 91.8 8.2

EXAMPLE 16

Except using IrCl(CO)(PPh3)2 ^' PPhs / α-AbOs ( 2 t% Ir ) as

catalyst, same method of example 12 is used and the distribution of resultant product is as following Table 5.

Table 5

Reaction

Conversion Yield (%) Selectivity (%) Temp. %

*CO Ethylene Ethane Ethylene Ethane

710 2.0 1.2 0.8 60.0 40.0

730 3.1 2.3 0.8 74.2 25.8

750 4.5 3.7 0.8 82.2 17.8

770 5.2 4.5 0.7 86.5 13.5

790 6.6 5.9 0.7 89.4 10.6

810 8.2 7.6 0.6 92.7 7.3

EXAMPLE 17

Except using Pd(PPh3) - PPha α-Al ₂ O ₃ (2wt% Pd) as catalyst, same method of example 12 is used and the distribution of resultant product is as following Table 6.

Table 6

Reaction

Conversion Temp. Yield (%) Selectivity (%) %

Ethylene Ethane Ethylene Ethane

710 1.7 1.1 0.6 64.7 35.3 730 2.6 2.0 0.6 76.9 23.1 750 4.1 3.4 0.7 82.9 17.1 770 5.5 4.8 0.7 87.3 12.7 790 6.7 6.0 0.7 89.6 10.4 810 8.6 7.9 0.7 91.9 8.1

EXAMPLE 18

Except using Pt(PPhs) ^• PPhs/ α-Al ₂ O ₃ (2wt% Pt) as catalyst, same method of example 12 is used and the distribution of resultant product is as following Table 7.

Table 7

Reaction

Conversion Yield (96) Selectivity (96) Temp. %

Ethylene Ethane Ethylene Ethane

710 1.1 0.7 0.4 63.6 36.4 730 2.2 1.5 0.7 68.2 31.8 750 3.2 2.5 0.7 78.1 21.9 770 4.7 4.0 0.7 85.1 14.9 790 6.0 5.4 0.6 90.0 10.0 810 7.5 7.0 0.5 93.0 6.7

EXAMPLE 19

Except using RuCl ₂ (PPh3)s ^' PPh--/ MgO (2wt% Ru) as catalyst, same method of example 12 is used and the distribution of resultant product is as following Table 8.

Table 8

Reaction

Conversion Yield (96) Selectivity (96) Temp. %

*( ^° C ) Ethylene Ethane Ethylene Ethane

710 2.3 1.3 1.0 ' 56.5 43.5 730 3.2 2.2 1.0 68.8 31.2 750 4.1 3.3 0.8 80.5 19.5 770 4.4 3.6 0.8 81.8 18.2 790 6.3 5.5 0.8 87.3 12.7 810 6.4 5.9 0.5 92.2 7.8

EXAMPLE 20

Except using RuCl ₂ (PPh3)s " PPhs / α-AkOs (0.5wt96 Ru) as catalyst, same method of example 12 is used and the distribution of resultant product is as following Table 9.

Table 9

Reaction

Conversion Yield (96) Selectivity (96) Temp. %

Ethylene Ethane Ethylene Ethane

710 1.3 0.7 0.6 53.8 46.2 730 1.9 1.2 0.7 63.2 36.8 750 3.0 2.3 0.7 76.6 23.4 770 4.6 3.9 0.7 84.8 15.2 790 7.1 6.4 0.7 90.1 9.9 810 8.2 7.5 0.7 91.5 8.5

EXAMPLE 21

Except using RuCl ₂ (PPh3)s ' PPhs / α-Al ₂ Os (4.0wt96 Ru) as catalyst, same method of example 12 is used and the distribution of resultant product is as following Table 10.

Table 10

Reaction

Conversion Yield (96) Selectivity (96) Temp. 96

Ethylene Ethane Ethylene Ethane

710 2.4 1.6 1.0 66.7 33.3

730 3.5 2.5 1.0 71.4 28.6

750 49 3.9 1.0 79.6 20.4

770 6.3 5.4 0.9 85.7 14.3

790 7.7 6.8 0.9 88.3 11.7

810 10.5 9.6 0.9 91.4 8.6

EXAMPLE 22

Except using RuCl. ^' χH ₂ O ^• PPhs / C.-AI2O3 (2wt96 Ru) as catalyst, same method of example 12 is used and the distribution of resultant product is as following Table 11.

Table 11

Reaction

Conversion Yield (96) Selectivity (96) Temp. 96

Ethylene Ethane Ethylene Ethane

710 0.4 0.0 0.4 0.0 100.0 730 1.1 0.5 0.6 45.5 54.5 750 1.8 0.9 0.9 50.0 50.0 770 2.6 1.7 0.9 65.4 34.6 790 4.4 3.5 0.9 79.5 20.5