Method for recovering mercury from waste mercury catalyst

Abstract

The invention discloses a method for recovering mercury from a waste mercury catalyst. The method comprises the following steps that (1) through the water solubility of HgCl2, the waste mercury catalyst is pretreated through water, the leaching reaction time is 80.0-90.0 min, the leaching reaction temperature is 50.0-80.0 DEG C, the liquid-solid ratio is (20.0:1.0)-(10.0:1.0), the magnetic stirring speed is 200.0 r / min, the pH value is 0.5-1.5, and at this time, the leaching rate of Hg2+ in the waste mercury catalyst is 85.5-93.2%; and (2) a leaching solution containing the Hg2+ is filtered bythe step (1), a suitable flow carrier, surfactant and solvent are selected, emulsion is made under high-speed stirring and mixing, and low-speed stirring for mass transfer is conducted with an external water phase containing the Hg2+ for a period of time. According to the method, an emulsion membrane system is adopted as a chemical separation method for recovering the mercury, the advantages of high efficiency, environmental protection, new type, easy operation and good selectivity are achieved, meanwhile, the operation flow is short, the operating conditions are mild, the operation cost andthe equipment cost are low, and the mercury in the waste mercury catalyst can be efficiently and quickly recovered.

Description

technical field [0001] The invention relates to the technical field of recycling waste mercury catalysts, in particular to a method for recycling mercury from waste mercury catalysts. Background technique [0002] The traditional production process of using waste mercury catalyst to recover recycled mercury is to first soak or boil the waste mercury catalyst with a certain concentration of alkali, and then indirectly heat it to 700 ℃ ~ 800 ℃ to separate it into Mercury vapor is condensed to recover metal mercury. Although this process has achieved industrial production, the mercury recovery rate is low, only about 65%. The pyrometallurgy process brings high energy consumption, risk of mercury vapor escape, and mercury furnace gas. There are many technical problems such as the combination of more dust and metallic mercury to form mercury soot. At present, the new technology of recycling mercury chloride in waste mercury catalyst by oxygen-controlled carbonization is the most ...

AI Technical Summary

Problems solved by technology

[0002] The traditional production process of using waste mercury catalyst to recover recycled mercury is to first soak or boil the waste mercury catalyst with a certain concentration of alkali, and then indirectly heat it to 700 ℃ ~ 800 ℃ to separate it into Mercury vapor is condensed to recover metal mercury. Although this process has achieved industrial production, the mercury recovery rate is low, only about 65%. The pyrometallurgy process brings high energy consumption, risk of mercury vapor escape, and mercury furnace gas. There are many technical problems such as the combination of more dust and metallic mercury to form mercury soot. At present, the new technology of recycling mercury chloride in waste mercury catalyst by oxygen-controlled carbonization is the most advanced. It uses the principle of high-temperature sublimation of mercury chloride to directly The recovery of mercuric chloride in mercury-containing activated carbon avoids the disadvantages of many conversion processes and low recovery rate. The overall recovery efficiency of mercuric chloride can reach more than 99%. The recovered mercuric chloride can be processed to produce new mercuric chloride catalyst. , but the dry distillation method is still a patent protection technology at present, and the investment and operation cost of production equipment is relatively high. , solidification / chemical activation method treatment, recycling and production of recycled mercury catalysts are also research hotspots, but most of the process steps are complicated and difficult to realize industrialization