US EPA

6763113 

Journal Article 

Determination of trace uranium in epoxy resin for semiconductor devices by fluorescence spectrometry after anion exchange separation and thenoyltrifluoroacetone liquid-liquid extraction 

Mitsumata, H; Kita, Y; , 

2005 

1 

Bunseki Kagaku / Analysis Chemistry
ISSN: 0525-1931 

JAPAN SOC ANALYTICAL CHEMISTRY 

TOKYO 

1101-1105 

WOS:000234116600009 

We have established a method for ppb levels of uranium in epoxy resins. This method involves the following procedure: 1) After 10 g of sample is decomposed at 800 degrees C, hydrofluoric acid and hydrochloric acid decomposition is achieved. 2) Sodium carbonate and potassium carbonate are added to the residue, followed by fusion. 3)The sample solution (in 8 N HCl) for anion exchange is passed through the column with packed the Muromacl-X8, so that uranium is adsorbed on the Muromac. Uranium is eluted with 0.5 N hydrochloric acid. The collected effluent is used to prepare a sample solution for thenoyltrifluoroacetone (TTA) extraction. 4) After adjusting the pH of the sample solution to approximately 7, 0.2 14 TTA/benzene extraction is achieved. The organic layer is stripped, and then the aqueous layer is heated to dryness. 5) The mixed flux (sodium fluoride + sodium carbonate + potassium carbonate) is added, followed by fusion. By using an obtained cake sample, the quantity of uranium is assayed by fluorescence spectrometry. Research has clarified that this method can assay ppb levels of uranium in epoxy resin for semiconductor devices.