A method for selectively reclaiming yttrium in crt fluorescent powder for doping to prepare ternary composite oxide catalyst

Abstract

The invention belongs to the technical field of environmental catalysis, and particularly relates to a method for selectively recovering yttrium in CRT fluorescent powder for doping to prepare a ternary composite oxide catalyst. Alkali fusion products are obtained; ammonia water is used to leach alkali fusion products, and the main impurity zinc is removed by solid-liquid separation; after leaching with dilute hydrochloric acid, two-step precipitation is used to enrich and recover rare earths, and dilute hydrochloric acid is used for secondary leaching to obtain rare earth leachate ; Obtain yttrium oxalate by photochemical method combined with chemical precipitation method; finally prepare ternary composite oxide catalyst by co-precipitation method. The invention is a method for selectively recovering yttrium in CRT fluorescent powder for doping to prepare a ternary composite oxide catalyst, which can efficiently separate, extract and fully utilize the rare earth elements in waste CRT fluorescent powder, and the doping of yttrium can obviously improve the efficiency of the catalyst. Low-temperature denitrification performance, lower catalyst production costs, and truly realize waste treatment with waste.

Description

technical field [0001] The invention belongs to the technical field of environmental catalysis, and in particular relates to a method for selectively recovering yttrium in CRT fluorescent powder for doping to prepare a ternary composite oxide catalyst. Background technique [0002] Nitrogen oxides (NO X ) In addition to directly damaging human health as a primary pollutant, it will also produce a variety of secondary pollution (such as acid rain, photochemical smog). NO X Control technology and countermeasures have been included in the key environmental science and technology issues for regional air pollutant control. my country's current NO X The emissions mainly come from automobiles, boiler combustion, industrial production, etc. Different fuels have different effects on NO X The contribution of emissions is different. According to statistics, among various fuels, coal combustion is the most X The largest source of emissions, accounting for more than 60% of total emi...

AI Technical Summary

Problems solved by technology

Catalyst is the biggest core of denitrification technology. At present, coal-fired power plants are widely using V 2 o 5 -WO 3 / TiO 2 SCR denitrification technology is a catalyst, which has high denitrification efficiency, strong anti-poisoning, and can meet environmental protection requirements, but the production cost is high and the activation temperature is high (300-430°C). The following flue gas treatment capacity is limited, and V 2 o 5 Toxic and easy to cause secondary pollution

Iron-based SCR catalysts have the advantages of cheap development, non-toxicity, and low pollution, but they also have the problem of low denitrification activity at low temperatures, which limits their large-scale industrial application.

Rare earth elements themselves have certain catalytic properties. Existing studies have found that the addition of rare earths cerium, lanthanum, and yttrium can improve the performance of the catalyst, but the addition of rare earths will also increase the cost of the catalyst.