Application of inductively coupled plasma atomic emission spectrometry in phase analysis of manganese carbonate,manganese oxide and manganese silicate in manganese ore
1. Shandong Institute of Geological Sciences,Ji'nan 250013,China; 2. Shandong Provincial Key Laboratory of Metallogenic Geological Process and Resource Utilization,Ji'nan 250013,China
Abstract:There is a great variety of manganese-containing minerals in manganese ore,and the classification is complex.However,the current methods for phase analysis of manganese ores have some disadvantages such as tedious operations,inconsistent procedures,and lack of detail description.In experiments,the manganese ores with different types and contents from various mining areas were selected.The monomineral test was conducted to select the leaching agent.Manganese carbonate was leached with 50 g/L aluminum nitrate in boiling water bath for 60 min.Manganese oxide was leached with 30 g/L hydroxylamine sulfate-1% (V/V) sulfuric acid in boiling water bath for 60 min.The residue was decomposed with acid to obtain manganese silicate.The content of manganese in treated solution was determined by inductively coupled plasma atomic emission spectrometry(ICP-AES).The method for the chemical phase analysis of manganese ore was established.The limits of detection were (in manganese):0.000 3% for manganese carbonate phase,0.000 5% for manganese oxide phase,and 0.000 3% for manganese silicate phase.One manganese carbonate raw ore and one manganese oxide raw ore were determined according to the experimental method.The relative standard deviations(RSDs,n=12) of determination results were less than 5.0%,which could meet the quality management requirements in DZ/T 0130.3-2006 The specification of testing quality management for geological laboratories.The proposed method was applied for the determination of certified reference materials of manganese ore for chemical phase analysis,i.e.,GBW(E)070256(manganese carbonate ore) and GBW(E)070258(manganese oxide ore).The relative errors(REs) of determination results of main phases were less than 1%.For other phases,the REs were less than 10%,which also could meet the requirements in DZ/T 0130.3-2006.