JPS5950651B2 - How to convert carbon monoxide - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for converting carbon monoxide, and more particularly to a method for converting carbon monoxide and hydrogen into lower hydrocarbons and hydrogen.

and a method for co-producing lower alcohols. Several methods have been proposed for producing hydrocarbons from carbon monoxide and hydrogen, including the Fischer-Tropitssch process [for example, Catalytic Reaction (1) Hydrogenation, Catalyst Engineering Course 6, pl2l-182 , Chijinshokan (1965)], there are problems such as large variations in the number of carbon atoms in the hydrocarbons produced and a large amount of carbon dioxide produced as a side reaction. The first method for producing alcohol from carbon monoxide and hydrogen is methanol synthesis.

Current industrial manufacturing methods, for example,
According to No. 1-44715, methanol is selectively produced and useful as a chemical raw material. However, in order to use methanol as an energy source such as fuel, it is desirable that it contains an alcohol with two or more carbon atoms, and a synthesis method for methanol suitable for these purposes has yet to be industrially established. Not yet.
Recently, a method for producing alcohol using a rhodium-based catalyst has been disclosed, for example, in Japanese Patent Publication No. 55-27891, but it has not been put into practical use due to the complexity of preparing or recovering the catalyst. The present inventors conducted intensive research to solve the problems in the conventional method, and as a result, they arrived at the present invention.

That is, in the present invention, a rhenium compound containing only rhenium as a metal component or metal rhenium is supported on a refractory metal oxide or a natural product or activated carbon containing a refractory metal oxide in the presence of a catalyst. This is a method for converting carbon monoxide, which is characterized by co-producing lower hydrocarbons and lower alcohols from carbon monoxide and hydrogen.

The catalyst used in the present invention has a rhenium compound containing only rhenium as a metal component and metal rhenium as catalyst components, and this catalyst component is combined with a refractory metal oxide or a refractory metal oxide as a carrier. It is a catalyst supported on natural products or activated carbon containing .

The rhenium compound that is a catalyst component is not particularly limited as long as it contains only rhenium as a metal component, but usually rhenium oxide, rhenium trichloride, rhenium pentachloride, ammonium perrhenate, etc. are used. Preferably used.

There are no particular restrictions on the refractory metal oxides, but oxides of zinc, aluminum, lanthanum, cerium, silicon, germanium, titanium, zirconium, thorium, vanadium, and chromium are practically used.
Preferably used. These refractory metal oxides may be used alone or in mixtures as a carrier. Natural products containing these refractory metal oxides, such as diatomaceous earth, activated clay and brick tiles, can also be used as carriers. A carrier prepared by a general method can be used, for example, as shown in Table 1 below.
A carrier prepared by the method described above is used.

The supporting method may be any conventional method, such as the impregnation method or the precipitation method. Any wet method, dry method such as mixing method, ion exchange method, etc. are employed.

Of these, the impregnation method is most preferred in practice. There is no particular limit to the amount of catalyst supported on the carrier, but it is usually 0.5 wt% as rhenium oxide (Re2O7) on the carrier.
Preferably it may be 1 to 20 wt%.

For example, 10wt of Re2O7 with rhenium as a carrier.
% of the supported catalyst can be obtained by immersing the support in an aqueous solution of ammonium perrhenate in a corresponding amount. It is preferable that the catalyst thus obtained be reduced prior to the reaction before use.

The conditions for reduction may be normal conditions, for example, the reduction temperature is 20°C.
It is said to be about 0 to 300°C. The conditions for converting carbon monoxide are as follows.

The ratio of carbon monoxide and hydrogen supplied to the reaction system is not particularly limited, but in practice it is preferably 0.5 mol or more of hydrogen per 1 mol of carbon monoxide, and 1 to 5 mol. It is particularly preferable that

The reaction pressure is preferably in the range of normal pressure to 300 kg/CITl2, particularly preferably in the range of 10 kg/- to 150 kg/mash. The reaction temperature is usually 180°C or higher, preferably 200 to 350°C.

The contact time with the catalyst varies depending on the reaction temperature and the like, and can be selected as appropriate.

The carbon monoxide conversion reaction of the present invention can be carried out by a continuous method or a batch method.

Carbon monoxide is thus converted to lower hydrocarbons and lower alcohols.

These lower hydrocarbons are mainly C1-4 aliphatic hydrocarbons, and methane is particularly abundant. The lower alcohols are mainly C1-4 aliphatic alcohols, and methanol and ethanol are particularly common. The ratio of lower hydrocarbon to lower alcohol can be controlled by selecting catalyst components, carriers, reaction conditions, and the like.

In the present invention, a catalyst that is easy to prepare and recover is used, and a mixture of lower alcohol and lower hydrocarbon suitable as an energy source can be easily obtained.

Hereinafter, the present invention will be explained in more detail with reference to Examples.
EXAMPLE A method for preparing a catalyst using SiO2.ZnO (5%) as a carrier will be described.

SiO2 was added to a solution of 1.28 g of Zn(NO3)2 6H (0.35 g as ZnO) dissolved in 50 ml of water.
(ID type 20-42 mesh) 7 g was introduced, water was evaporated using a rotary vacuum evaporator, and then dried at 100°C for 3 hours to support Zn(NO3)2 on SiO2.

NH4HCO3l. The above SiO2.Zn(NO3)2 was added to a solution of 5 g dissolved in 20 ml of water, stirred for about 5 minutes, filtered and washed, and dried at 80° C. for 15 hours. This was fired at 450° C. for 2 hours using a Matsufuru furnace to obtain a carrier. Next, ammonium perrhenate (NH4ReO4) 0.
95 g was dissolved in 50 ml of water, the above-mentioned carrier was added to this aqueous solution, water was evaporated using a rotary vacuum evaporator, and then dried at 80° C. for 15 hours to obtain a catalyst.

Prior to the reaction, catalysts with rhenium supported on various carriers,
Reduction was carried out at 240-300° C. for 2 hours using gas with a H2/CO molar ratio of 2-3. A reaction was carried out using the catalyst thus obtained, and the results shown in Table 2 were obtained. Comparative Example Reaction No. 2 in Table 2 was carried out using only a carrier that did not support rhenium as a catalyst. As a result of carrying out the same reaction as in 1, the reaction hardly proceeded.

Claims (1)

[Claims] 1 A rhenium compound containing only rhenium as a metal component or metal rhenium is mixed with carbon monoxide in the presence of a catalyst supported on a refractory metal oxide or a natural product or activated carbon containing a refractory metal oxide. A method for converting carbon monoxide, characterized by co-producing lower hydrocarbons and lower alcohols from hydrogen.