Catalytic Spectrophotometric Determination Of Trace Rare Earth Elements

Rare earth elements are a group of typical metal elements which have special characters, They can be used in traditional industries of metallurgy, nonferrous metal smelting, petrochemicals, glass, ceramics and household appliances. And now they can be used in six high-tech industries which are information, biology, new materials, new energy, space and ocean. REE is an essential functional material for high-tech and international cutting-edge technology. Therefore, the strengthening of China's rare earth determination is of great significance to the development of rare earth industry. Most of the measurement of trace rare earth elements which are widely used at home and abroad are complicated, and some analysis methods require expensive analytical instruments and reagents, the cost are high.This paper establishes a new method which use catalytic kinetic photometry to determine rare earth elements directly. It preliminary study of the reaction mechanism and has a new system of rare earth elements analysis. It has satisfactory results. (1) crystal violet-potassium periodate-La (Ⅲ)-Sulfuric Acid System. The limit of detection is 1.75 X 10-6g/L,the linear range is 0.01-0.05μg/ml.The existence of a large number of metal ions have no impact on the experiment. The recovery is between 97%and 100%.The relative standard deviation is between 2.75%and 3.51%.It has satisfactory results.(2) Methyl violet-potassium bromate-Sm(III)-Sulfuric Acid System. The limit of detection is 6.5 X 10-8g/L, the linear range is 0.05-0.2mg/L.The sensitivity of this experiment is high and the rate of the response is quick. The existence of a large number of usual ions have no impact on the experiment. (3) potassium periodate-CPA mA-Sc-hydrochloric acid system. The linear range is 0.008-0.320mg/ml, the limit of detection is 3.04 X 10-6g/L. Also we studied the interference of other ions to the experiment. It is found that the presence of a large number of common ions has less impact on the experiment. It can be directly measured without any masking agents.