CS200414B3 - Catalyst for cleavage of the earth gas and gaseous hydrocarbos by the water wapour - Google Patents

Description

The invention is dependent on US. No. 125473 and relates to a catalyst for the cleavage of natural gas and gaseous hydrocarbons by steam, prepared according to U.S. Pat. No. 125473 by saturating the corundum support with a nickel-aluminum nitrate solution.

Catalysts for the digestion of natural gas and gaseous hydrocarbons with water vapor in cyclically and continuously operated plants for producing hydrogen-rich gas are known.

The prior art catalyst supports have always met only the main requirement of the technology for which they were intended. Ceramic supported catalysts containing above 10% of silica and, in addition to aluminum oxide in formě-form, also active in the catalyst were determined for cleavage in cyclic plants where the heat resistance and compressive and abrasion strength requirements of the catalyst were not so high. form. The catalysts operate at temperatures of 750 to 850 ° C. Higher and lower temperatures degrade it, especially by spinel formation. Such a catalyst is the catalyst according to U.S. Pat. No. 125473.

The catalyst support intended for cleavage in cyclically operating equipment, in which it is thermally and mechanically stressed, consists mainly of corundum, which ensures high thermal stability and mechanical resistance to compression and abrasion. The binder used, such as kaolin, feldspar, bentonite and preparation technology, do not allow higher porosity above 25%. As a result, the nickel content after one carbonation is low and reaches 1 to 3%. Catalyst activity is lower and the operating temperature is above 750 ° C. The catalyst can also be operated at po200 414

200,414 at very high temperatures above 900 ° C, without the formation of nickel spinel threatening its activity.

Disadvantages of said supports and catalysts are eliminated by the invention, characterized in that the corundum carrier consists of 80 to 95 wt. at a temperature of 1400 to 1450 ° C, it contains 1 to 15%, preferably 3 to 5% boron trioxide as a binder as a binder.

This catalyst can operate from low operating temperatures of 550 ° C to high temperatures of 900 ° C without reducing its activity by nickel spinel formation.

The basic component of the catalyst support is corundum in an amount of 80 to 95% by weight, obtained by firing alumina at a temperature of 1750 ° C. After crushing, the corundum grains are re-atomized with the binder additive, which is glass borate frit in an amount of 1 to 15% by weight, preferably 3 to 5% by weight. Another component is a filler, namely cork, crushed stones or plastics, which give the carrier the necessary porosity after firing. After forming and firing at 1400 to 1450 ° C, the bearer has a high corundum content which, in conjunction with the binder, provides it with a compressive strength above 20 MPa and a high abrasion strength, thermal stability allowing at least 15 abrupt cooling by immersion in water and inactivnoat and active ingredients, in particular nickel. At the same time, this method of preparation allows the porosity of the carrier to be selected in the range of 20 to 70%. Suitable fillers can be further treated in a wide range of 5 to 10 to 1 macroporosity and microporosity. Macroporosity allows easy access of the gas to the interior of the catalyst at high spatial velocity while providing a high and high nickel content within the catalyst. 8 to 10%.

The binder used, a glass borate frit, allows to achieve high porosity and strength with a relatively small amount of binder, which therefore does not substantially increase the silica content of the catalyst. Low silicon dioxide content in the range of 0.5 to 10% ensures the resistance of the catalyst to the formation of irreversible SiOg - NiO compounds at temperatures above 900 ° C. Another very important function of boron oxide in the carrier is to replace alumina in the i-form. The carrier components are capable of catalytically promoting the cleavage of the feedstocks. The carrier itself is composed of alumina in the .beta.-form whose catalytic ability to cleave the C-C and C-H bonds in hydrocarbons is very low. Boron oxide, on the other hand, supports this carrier, so that the support acts as an active ingredient in the catalyst.

The catalyst itself is prepared by saturating the support with solutions of dicalates of the respective metals. The high porosity of the carrier allows 8 to 10% nickel in the catalyst to be achieved with one satiety. The higher nickel content of the catalyst favorably affects its activity, especially at low temperatures, and ensures a sufficient catalyst life.

Catalysts intended for resolution at low temperatures are prepared by saturating the support according to Art. No. 147495 and No. 147119. The active ingredient in addition to nickel is aluminum oxide in its' form in an atomic mass ratio of 1 Al to 15 Ni, preferably 1: 6.

200 414 calcium lichen that protects active nickel from spinel formation.

The higher temperature cleavage catalysts are prepared by saturating solutions in which the active ingredient is nickel or cobalt, and the promoter is magnesium and has, on the one hand, protecting the active nickel and promoting its reduction.

Example

The catalyst support is prepared from a mixture of 90% by weight corundum and 10% by weight glass boron frit. 40% of the basic mixture of cork pulp is added to the mixture. The whole mixture is thoroughly mixed and formed by cutting the cast wet plate into a 15 mm cube. This is followed by drying at 100 ° C and firing at 1450 ° C.

The catalyst support has basic physical properties:

Bulk density Porosity

Specific surface Strength

Abrasion

900 gA 30 «below 1 m / g above 20 MPa%

The catalyst itself is prepared by saturating the support in a solution of nickel, aluminum and calcium nitrate in which the individual components are in an atomic mass ratio of 6 to 1 to 0.1. After saturation, the catalyst was rapidly fired at 500 ° C.

The catalyst contains 8.95 wt. nickel

Bulk density 1000 gZL

Other carrier values remain unchanged.

Claims (1)

Catalyst for the cleavage of natural gas and gaseous hydrocarbons by steam, dependent on MS. No. 125473, prepared by saturating a corundum carrier with a solution of nickel and aluminum nitrate in an atomic mass ratio of 4 to 9 to 1 and calcium and strontium, barium and uranium in an atomic mass ratio of 1 to 0.1 to 0.4, characterized in that The corundum carrier, composed of 80 to 95% by weight of Λ-alumina, prepared by melting at 1750 ° C, crushing to a grain of 100 to 200 nm and re-cementing at 1400 to 1450 ° C, contains glass boron frit as a binder in an amount of 1 to 15% _t , preferably 3 to 5% boron oxide.