CS46291A2 - Method of gases catalytic reverse cleaning and equipment for this method realization - Google Patents

Description

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BACKGROUND OF THE INVENTION The present invention relates to the catalytic purification of gas, in particular to organic impurities.

There is a known method of purifying gases by cyclically passing the uncleaned gases through two layers of the same catalyst located between two layers of ceramic or metal. The gas permeation takes place in two different directions and a steady supply of heat required to initiate the reaction occurring in the central portion of the apparatus (Polish Patent No. 126,861). So far, platinum and oxide catalysts have been used in the catalytic purification of gases. Platinum catalysts have a higher efficiency, but are more expensive than oxidation catalysts, which are less efficient.

The present invention is based on the fact that a mixture of gases containing impurities, in particular organic compounds, is passed through catalytic bearings of different activity, wherein the catalytic bearings are preheated from the space between them. Advantages of the invention over the prior art are that high efficiency is achieved at a substantially lower cost of the catalyst. Positive properties of the platinum and oxide catalysts are complementary to the method of the invention, and the invention has no disadvantages.

According to the invention, the purified gases are discharged by two catalysis bearings of varying efficiency located between the two heat-storing filler layers. The release of purified gases occurs in cyclically changing directions. Between the two catalytic bearings there is a heat source needed to pre-heat the k and a. Bearing bearings. For the first catalysis, a catalyst with a higher activity, e.g., platinum, is used, and a lower activity catalyst, e.g. an oxide catalyst or a low platinum catalyst, is used for the second catalyst bed. The volumes of the catalytic deposits can be advantageously different, for example, the ratio of the more active catalyst deposit to the less active is at least 4: 15 or more. The volume of both catalytic bearings is given by their height with the same foundation or cross-sectional area of both bearings, but this is not a condition; the change in volume can also be due to a change in cross-section or change in both cross-section and height. The height of the heat accumulating fillers may be different on the side of one catalytic bearing against the filler side of the second catalyst bearing. An important condition for the high efficiency of the two catalysts used is the location of each catalyst, i.e., both the higher efficiency catalyst and the lower efficiency catalyst in the catalyst catalyst itself. A heat source is placed between these bearings. Bearing 3 with a more active catalyst becomes the initiator of the whole system at a relatively low temperature. The initiation of the reaction in the more active catalyst bed causes heat to be excreted and the second temperature increased to a less active catalyst, which increases activity. In the short term, after initiation of the reaction in the more active catalyst deposit, the introduction of the two catalysts is accompanied by an accompanying deposit in which the activity of the two catalyst beds is almost equivalent.

In the accompanying drawing, an exemplary embodiment of the invention is illustrated in a schematic cross-section, using the present invention. In the catalyst reactor 11, e.g., cylindrical with a diameter of, for example, 250 mm, there are two heat-storage layers 2, 2, e.g., ceramic, formed by aluminum silicate with grains having a diameter of about 6 mm. The height of the filler layers, 2 in this case, is 40 cm, but may vary. The first catalyst bearing 4 with a less active catalyst has a height of, e.g. 15 cm, the second catalyst deposit 2 G the more active catalyser has eg a height of 4 cm. A heating chamber 13 with an electric heater 6 and a thermal sensor 8 is provided between the two catalyst supports 4, 5. From both sides, the reactor 2 is fed upstream of the filling layers 1, 2 and 3, respectively. > 20 ('fan') pipe 14s with pairs of closed and opened valves 9, 11, 11, 12 and outlet 5. The first catalyst layer 2 on the catalyst side with the higher activity is smaller than the second filling layer 3 on the catalyst side. Examples of utilization of the inventive method are as follows: Example 1 (comparative): In both catalyst deposits 4, a granular platinum catalyst (according to Polish Patent No. 146,901) containing 0.06% platinum was used. 1 / h of air containing 1.0 q / m 2 acetone The valves 9, 10, 11, 12 caused a change in flow every 4 minutes, closed and opened two times, and the power of the electric heater 6 was 0.8 kW. 270 DEG C., the conversion of acetone was 95% on average, Example 2 (comparative): The experiment of Example 1 was carried out using a copper-zinc catalyst according to the invention. It was found that at 270 ° C the conversion of the acetone was 25 °, the conversion of 95% was achieved at 350 ° C. Example 3: The same experiment was repeated with a platinum catalyst in catalyst bed 5 and a copper-zinc catalyst in catalyst bed 2. At 270 ° C, the acetone conversion was 93%, 95% at 283 ° C.

Similar results have been obtained in the catalyzing of other organic compounds (xylene, gasoline, ethylene). The 95% conversion of these compounds was at temperatures close to when it was. used in both catalyst bearings 4 ·? 2, a platinum catalyst, as well as the use of platinum catalyst and copper catalyst in the 4- (5) catalysts, where only the oxidation catalyst was used, the temperature of the conversion was 9% higher by 50 ° C. ° C - 100 ° C. Analoqic dependence was found when a platinum catalyst containing 0.06% platinum and 0.03% platinum was used in one or more bearing bearings A, 5. In other experiments, it has been found that the use of both types of catalysts at a less effective and less potent ratio in the above experiments causes the activity of both catalysts to be approached with higher activity.

Conversely, when the ratio of platinum catalyst to oxide or catalyst is less than A: 15, a rapid approach of the activity of both catalysts was found to activate the oxide catalyst.

The process for carrying out the process of catalyzing impurities in the airfoil of the invention allows for good, perfect catalytic nearly equivalent technical effects. At the same time, it significantly reduces gas cleaning costs by using catalysts with less activity but cheaper than higher activity but more expensive catalysts. '

Claims (7)

/ y uifi CLAIMS 1. A process for the catalytic reverse gas purification using impurities in the cyclically varying proportions of two catalyst deposits located between two heat-storing filler layers, characterized in that the gas mixture containing impurities, especially organic compounds, is discharged. two catalyzed bearings of different activity, with both catalytic bearings being preheated from between. 2. A process according to claim 1, wherein a higher activity catalyst and a lower activity catalyst deposit catalyst are used for one catalyst bed. 3. A process as claimed in claim 1 or 2, characterized in that the catalyst deposit with the lower activity forms an oxidized catalyst and the higher-activity catalyst deposit forms a platinum catalyst. 4. The method of claim 1 or 2, wherein the lower activity catalyst deposit is a platinum catalyst with a lower platinum content and the higher activity deposit is a platinum catalyst with a higher platinum content. 5. A method according to claim 1 or claim 2, wherein the method is as follows. that the volume ratio of more active catalysis 1 to less active is at least 4: 15. 6. Apparatus for carrying out the process according to claim 1, characterized in that two catalyst deposits (4, 5) are arranged in the catalyst reactor (1) between two heat-storage filling layers (2, 3), one of which has higher activity and the other with lower activity and an electric heater (6) is provided between them. 7. An apparatus as claimed in claim 6, wherein the first catalyst-filling layer (2) with higher activity is smaller than the second catalyst-filler layer (3).