SU311493A1 - - Google Patents

Description

The invention relates to the adsorption purification of gases from mercury vapor and can be used for sanitary and technological purification of air and gases from mercury vapor.

A known method for purifying gases from mercury vapors by adsorption on a cation exchanger in silver form, followed by decomposition of the resulting silver amalgam with nitric acid and the separation of silver and mercury.

However, this method is characterized by the need to use significant amounts of precious metal in the process and the difficulty of regenerating the sorbent, which requires the separation of metals with similar properties, in particular, complete purification of mercury from silver.

The purpose of the invention is to simplify the regeneration of the resin and reduce the cost of the process. For this, in the proposed method, cation exchanger in mercury () form is used.

When this sorbent interacts with mercury ions, a reaction occurs: + -fHg ° - R2ng2 + (R is the radical of the functional group of the cation exchanger).

Regeneration of the cation exchanger is carried out by leaching of mercury with nitric acid (5-10% HNOZ), followed by release of mercury from its nitrate solution by known methods and treatment of the cation exchanger in the H-form with a solution of salt or direct displacement of Hg2 +

from caponite salt solution

ng2 +.

The total capacity of the cation exchanger but mercury vapor is equal to the amount of bivalent mercury contained in it, and for KH-2 sulfonic cation exchanger it is about 30 wt. % (by weight of sorbent). Under dynamic conditions, when air containing mercury vapor is passed through a layer of cation exchanger in the Hg + form (3.5–4.5 mg eq / g, the bed is 30–35 mm in height before the mercury slip into the outgoing gas equal to 0 , 01 mg / nm, absorbs 150–200 mg of mercury per 1 g of sorbent (15–20 wt.%).

PRI me R. For purification of gases containing X from 10 to 60, -g / nm of mercury, the KU-2 slot cation exchanger containing from 3.5 to 4.5 mg is used strongly. mercury per g matrix.

In a glass tube with a diameter of 8. ". N, 1 g of caponite KU-2 containing 230 mg of Hg- + is placed. The height of the layer is 35 mm, the grain size is 0.4-0.5 mm. Air containing mercury in a concentration of from 20 to 40 mg / nm (relative humidity 90% at 20 ° C) is passed through a layer of ion exchanger at a rate of 2 AJ.MUH (0.7. As the gas passes, dark transparent nonite grains acquire a bright, opaque shade, which gradually spreads along the length of the ion exchanger in the direction of the gas flow. Mercury leakage (0.01 mg / m occurs after 45 hours of work,

when 5.53 nm of air is missed and 152 mg of mercury is absorbed. Prior to the alignment of mercury mercury at the inlet and outlet of air from the column, 8.9 lg of gas are passed in and 234 mg of mercury are absorbed, i.e., 15 weight is absorbed by mercury. % by weight of sorbent, to saturated sorbent - 23 wt. %

Mercury is desorbed from the ion exchanger by passing 5% HNOs, 460 mg of mercury is detected in the resulting solution, which corresponds to the complete displacement of the original and absorbed mercury. In order to regenerate the polyurethane, half of the obtained solution of 10 g / l HO- (N03) 2 is passed through cation exchanger, and 230 mg of mercury is recycled.

Repetition of mercury sorption from the air on the regenerated ion exchanger yields results, and the last n are shown.

Formula and 3 about b ete n and

The method of purifying gases from mercury vapor by the adsorption of e of a cation exchanger used in reactive form and by regenerating it with an aqueous solution of nitric acid, characterized in that, in order to simplify the regeneration of nitrite and the reduction of the process, cation exchange resin is used in the form of bivalent mercury.