SU939044A1 - Adsorbent for cleaning gas from hydrogen sulphide - Google Patents

Description

(5) ABSORBENT FOR CLEANING GAS FROM HYDROGEN

The invention relates to the field of gas purification from hydrogen sulfide by absorbents to obtain elemental sulfur and can be used in the gas processing and chemical industries. Existing absorbents for the purification of gas from hydrogen sulfide, despite their effectiveness, have significant drawbacks. For example, in the Stretford process, the following components are used as the absorber: soda, sodium metavanadate, sodium tartrate, and the isomer of 2,7-anthraquinone disulfonic acid. At the stage of absorption, hydrogen sulfide is rapidly absorbed by the medium, then a slower oxidation of hydrosulfide ion to elemental sulfur occurs under the influence of five-valent vanadium. It takes about 10 minutes to complete the reaction. For this purpose, the solution is kept either in the lower part of the absorber or in a special container. The Stretford process provides deep gas cleaning from hydrogen sulfide (mg / m) and obtaining fused sulfur with a purity higher than 99.5% GO. The main and significant drawback of the process is the formation in the absorption solution of a by-product of the reaction, thiosulfate, about 20%, as well as a low regeneration rate. The closest to the proposed technical essence and the achieved result is an absorbent for gas purification from hydrogen sulfide based on an aqueous solution of dimethylformamide with the addition of dimethylamine, taken from Goty at the following weight ratio of components, parts by weight: dimethylformamide 100 and dimethylamine 0.05 5, 0 2 Despite the simplicity of the technological scheme of the cleaning process using the specified absorbent is not without drawbacks, which limits its use. For example, for complete regeneration of the dnmethylformamide solution, it is necessary to contact it with molecular oxygen, followed by treatment of the absorbent with formic acid. Periodic addition of dimethylamine is necessary to maintain the absorption capacity of the dimethylformamide solution. The absorption capacity does not exceed 1.4 g / l. The efficiency of extraction of hydrogen sulfide with dimethylformamide decreases sharply due to incomplete regeneration of hydrogen sulfide and is (70-80). The regeneration rate is also low (50 min), which reduces the capacity of the plants, and the resulting sulfur is difficult to remove from the solution. The purpose of the invention is to develop an absorbent for the purification of gas from hydrogen sulfide, which has an increased absorption capacity. This goal is achieved in that the absorbent for gas purification from hydrogen sulfide based on aqueous solution Example 2. Gas containing 0.5% hydrogen sulfide is fed to a scrubber for cleaning, where it is irrigated with a solution containing,%: dimethylformamide 30; diethanolamine 0.1, polyphthalo-55 cyanine cobalt 0.05 and water 69.85. The scrubber achieves the degree of gas purification from hydrogen sulfide, which

is 99.930%. Absorbency of the absorbent is 1.9 g / l.

The solution from the scrubber enters the reactor (bubbling machine) and is blown with air. When this occurs, the almost complete oxidation of absorbed hydrogen sulfide (99.9) of dimethylformamide with the addition of an amine as an amine contains diethanolamine and additionally contains cobalt polyphthalocyanine in the following ratio of components, weightD: Dimethylformamide30-50 Diethanolamine 0.1-1.0 05 WaterOther Use of the proposed absorbent leads to an increase in the absorption capacity (by 20-30), an increase in the regeneration rate of the solution by a factor of 3, and also an almost complete conversion is achieved. bsorbirovannogo hydrogen sulphide into sulfur. The resulting high quality sulfur (99.9) is easily removed from the system. Example 1 An absorbent is prepared by mechanically mixing dimethylformamide, diethanolamine, and cobalt polyphthalocyanine with water in appropriate ratios. Data on the absorption capacity of the absorbent at various ratios of the components are presented in the table.,

and flotation of the resulting sulfur. The regeneration time is 25 minutes.

Example 3. According to example 1 with the composition of the absorber D: dimethyl forms and kQ of diethanolamine 0, S polyphthalocyanine 0.01 and water. Absorbency of absorbent 2.0 g / l. The degree of gas purification from hydrogen sulfide is. Regeneration temperature. Regeneration time 20 min. The conversion of hydrogen sulfide to sulfur is 99.99.

Example 4. In example 1, with the composition of the absorber,%: dimethylformamide 50, diethanolamine 1; cobalt polyphthalocyanine 0.005 and water 8.995. Absorbency of absorbent is 2.1 g / l. The degree of gas purification from hydrogen sulfide is 99i99%. The regeneration temperature is 20 s. Regeneration time 10 min. The conversion of hydrogen sulfide to sulfur is 99.99%.

The economic effect of the introduction of the proposed absorber in the national

The household is 1.5 million rubles. in year.

Claims (2)

1. Cole A.L. and Rizenfeld, F.S. Gas cleaning. M., Nedra, 1968, with 218 .. 2.US Patent ff 3777010, cl. 23-2, published in 1973 (prototype).