A method for extracting rare earth phosphors from spent cathode ray tubes by using microorganisms

Abstract

The invention relates to a method for recovering rare earth from waste cathode ray tube fluorescent powder through microbial leaching. The method is characterized by comprising the steps of (a), performing pretreatment: drying fluorescent powder until constant weight is achieved, and grinding the dried fluorescent powder with constant weight into fine powder with a grinding instrument for standby application; (b), performing microbe selection and culturing: selecting funguses or bacteria as leaching microbes, and selecting liquid cane sugar culture mediums and beef extract peptone culture mediums as culture mediums for separately culturing the funguses and the bacteria; (c), performing leaching treatment: adding levigated fluorescent powder into the culture mediums containing strains, putting the culture mediums with the levigated fluorescent powder into a vibrating culturing box, performing culturing for some time, performing filtration, obtaining waste slags, collecting thalli, and decomposing the thalli so as to obtain a leaching solution containing rare-earth elements. Through the adoption of the method, not only can the innocent treatment of the waste fluorescent powder be realized, but also rare earth resources can be recovered.

Description

technical field [0001] The invention belongs to the field of hazardous waste treatment and comprehensive utilization, in particular to a method for extracting rare earth elements from waste cathode ray tube (CRT) fluorescent powder by using microorganism wet method. Background technique [0002] CRT phosphors are coated with rare earth phosphors on the inner surface of the cathode ray tube screen glass according to a certain structure. my country is a big country in the production and use of cathode ray tube (CRT) displays, and the output of CRT accounts for about 60% of the total output in the world. According to statistics, there are about 400 million CRT TVs and nearly 20 million computers in China. With the acceleration of updating of electronic products, new displays replace traditional CRT displays, resulting in more and more CRT displays being eliminated. It is estimated that the obsolete numbers of TVs and computers are more than 5 million units each year, and the ...

AI Technical Summary

Problems solved by technology

Due to the different occurrence states of rare earths in different phosphors, and the different non-rare earth components; although the research on the recovery of rare earths in phosphors has achieved certain results, there are often complex processes, low rare earth recovery rates, high costs, and low economic benefits. and other issues, the content of rare earth components in waste phosphor powder is often low, and it is necessary to use acid and other reagents to remove a large amount of impurities in the process of recycling rare earth, which may cause a greater degree of secondary pollution