SU886955A1 - Method of cleaning gases from mercury vapour - Google Patents

Description

The invention relates to methods for the purification of gases, in particular hydrogen, from mercury vapor.

Known methods of cleaning waste gas from mercury vapor by absorbing them with a solution of sodium disulfide 1.

The disadvantage of this method is the low degree of purification (91.5-98%).

The closest result to that proposed by the technical essence and to achieve fm y is a method of purifying gases from mercury by contacting them with ferric chloride solution containing hydrogen chloride in an amount of 5-50 g / l 2.

The degree of gas purification according to this method is 99.2-99.5%, i.e. it does not provide complete recovery of mercury.

The aim of the invention is to achieve 100% gas purification from mercury vapor and reduce the cost of the cleaning process.

The goal is achieved by the fact that mercury is absorbed from gas by the production of silicon tetrachloride — a solution of chlorides of the following composition, weight. %:

ReС1з

9.0-21.0

Solution 0.4-0.8

A1С1з 5.0-14.0

HC1 1.0-3.0

SiOa 0.8-2.2

IGO Else

The extraction of mercury is based on the reaction of its interaction with metal chlorides.

Under industrial conditions, the method is carried out as follows. 5 A gas contaminated with mercury vapor is passed through a column with Raschig rings, filled with a 21% solution of metal chlorides. At the outlet of the column, the gas is analyzed for 10 mercury content.

N p and meer. A room-temperature gas with an average mercury content of 5-8.5 mg / m is sent to a laboratory column 25 mm in diameter with a height of the solution layer in a steady state of 250 mm (the amount of solution is 100 mm). The concentration of the solution in 1 and 2 experiments is as follows; a, weight. % (minimum components taken): PeClg - 9.0; P-eC-0,4; AlCU- 5.0; HC1-1.0; SiO2-0.8; the rest is water. The concentration of the solution for experiments 3 and 4 was taken with the average values of the components, wt. %: PeClg - 15.0; FER - 0.6;

25 AlCl3 - 10.0; HC1 - 2.0; SiOa - 1.5; the rest is water.

For experiments 5 and 6, the concentration of the prepared solution is as follows, weight. % (maximum values of components are taken): ReCl3 - 21.0; FER - 0.8; A1С1з -

14.0; HCl - 3.0; SiOa - 2.2; the rest is water.

The gas flow rate through the column is 1 l / min. The purified gas is analyzed for mercury content by a colorimetric method. Data on the degree of gas purification of vapor from mercury are presented in the table.

The table shows that the proposed method provides 100% gas purification from mercury vapor, and an increase in the concentration of the solution leads to an increase in the saturation time of the solution with mercury. The proposed method of purifying mercury from a gas reduces the cost of the purification process, since for this purpose, waste from the production of tetrachloride, p, and pure silicon, a solution of metal chlorides is used.

Claims (2)

1. USSR author's certificate number 325980, cl. B 01 D 53/14, 1971. 2. USSR author's certificate number 326969, cl. On 01 D 53/14, 1970.