SU47681A1 - The method of obtaining sulfuric acid andihydride from sulfates - Google Patents

Description

The invention aims to develop the chlorine industry, which will allow the processing of such types of local raw materials as gypsum, anhydride, Glauber's salt, whose reserves are estimated at hundreds of millions of tons.

The proposed method consists in the following. Sodium or potassium sulphates of the Earth-metal, in the presence of additives (see below) or a mixture of alkaline-earth sulphate with sodium or potassium sulphate, with or without additives, are affected by excess chlorine at a temperature of about 750-950 °. The following reactions proceed according to the following schemes:

MS04 + Cl2 - MClg + SOa + O, (M - alkaline earth metal)

MgSO., + Cla- 2MS1 - + - SOa + O

(M - alkali metal).

The gases SOg, Cla and Og released from the furnace are sent to an acid-resistant bed washed with water to oxidize the sulfurous anhydride to sulfuric with the simultaneous formation of sulfuric and hydrochloric acid by the reactions:

1. 302 + Н20: Н280з. 2. Cls + HjOI HCl-f NOS1.

3. NOS1 + N25Oz: N, 5O, NS.

As the water of the absorption tower is saturated with sulfuric and hydrochloric acids, the resulting acid solution is continuously drained from the bottom of the tank into the evaporators, where hydrogen chloride gas is separated, which is absorbed by the usual method, and 90-95% sulfuric acid remains in the evaporators. acid.

The proposed method allows to obtain pure hydrochloric and technical sulfuric acid. As additives used in quantities of 5-10% by weight of sulfate, take: for alkaline earth KC1, NaCl, KoSOi, MpCl, MnO or pyrolusite, NiSO, NiClg, ReaOz, FegOi or iron ore, MnSO4, MnCla and in quantities of 30 -250% SiO of any modification or, for alkaline, the same additives in amounts of 4-10%, as for alkaline-earth, except for KoSO and NajSO and 30-250% of SiOg of any modification.

With the addition of 5–10% of the catalyst, they are: KCl, NaCl, K2SO4, MnCl2, MnOo, pyrolusite, NiSO, Fe, Oz, FesSO. iron ore, MgSO4, MgClo, and 30-250% SiOg of any modification or Na2SO4, at temperatures of 750-950 give the following SO2 outputs.

in the presence of 5-10%

1. KCI, NaCl and KGZ O

2.MnClg, MnO3 and pyrolusite

3.NiSOi and NiCla

4. Fe2O8, FesO.i and yellow. ore

5. MgSOi and MgCla

6. 30-250 th NaaSOj or SfOg

The role of additives is reduced to the release of activated chlorine, which is known to have a higher chemical activity than ordinary chlorine gas. For example, at a temperature of 300 ° C, CuSO4 is chlorinated

CuSOi + Cla - CuCls + SOg + Og

in the presence of a substance capable of combining with chlorine, at a temperature of 460 °, the CuClg decomposes to a greater or lesser degree:

2CuCl2-Cu2Cl2 + aKT. Cl

with the release of activated chlorine, which is the reason for increasing the yields of SOs, since it accelerates the decomposition of sulfates.

Formed with free chlorine reacts and gives CIC, which again releases activated chlorine, etc.

When SO is obtained from CaSO in the usual way (with the addition of clay and coal), the gas concentration reaches a maximum of 7.2% by volume with a low oxygen content (up to 1%); thus, in order to oxidize the resulting SOa to 5O3, it is necessary to dilute it accordingly with air. KpOiVie addition, to simultaneously obtain Portland cement (receiving output SOj for alkaline sulfates in AND f "

18.5 36.6.

92.1-100 70.0

 100 21.3 90-98.2 23.6 95.0-100 92.1

/ - 100 in the presence of 30-250 4 SiOg

In an amount of 50% clinker versus a conventional method of producing it, a temperature of 1450-1470 is required, while with the proposed method the process can be carried out at a temperature of 750-950 °.

The subject matter of the invention.

Claims (3)

1. A method for producing sulfur dioxide from alkali metal and alkaline earth metal sulphates, characterized in that said sulfates at a temperature of about 750-950 ° in the presence of additives KCl, NaCl, MnClj, pyrolyzite NiSO, iron ore, MgSOi, SIO2, taken individually or in combination, they are chlorinated. 2. A method according to Claim 1, characterized in that, in the preparation of sulfur dioxide from alkaline earth metal sulfates, in addition to these additives, potassium or sodium sulfates are used, or both, or in combination with the additives listed in the first paragraph. 3. Acceptance of the method according to paragraphs. 1 and 2, characterized in that the gases released from the furnace are directed to irrigated towers in order to obtain sulfuric and hydrochloric acids.