Determination of arsenic in ilmenite by graphite furnace atomic absorption spectrometry after microwave digestion and ion exchange resin separation
ZHANG Li*1,2,HAN Guo-cai1(1. Basic Course Apartment,Lanzhou Polytechnic College,Lanzhou 730050,China;2.College of Chemistry and Chemical Engineering,Northwest Normal University,Lanzhou 730070,China)
A method for the determination of arsenic in ilmenite by graphite furnace atomic absorption spectrometry (GFAAS) with microwave digestion and ion exchange resin separation was established.The experimental conditions that influence the sample separation and enriching such as pH of solution,elution conditions and so on were investigated and optimized.At pH 6.0,arsenic was retained on the strong base type ion exchange resin of 717 type,then eluted with 0.3 moL/L nitric acid and determined by GFAAS.The method could avoid the disturbance of impurity in the sample,and was proved to be accurate and reliable. The linear range of the method is 0.33 μg/L to 100 μg/L,and the detection limit is 0.10 μg/L.The method has been applied to the determination of arsenic in standard reference samples and the results are in good accordance with certified values.The method has been applied to analyze the sample with the RSDs of 2.85%-7.82% and the recoveries of 98.0%-104.0%.