Abstract：The ion selective electrode-reverse Gran graphics was proposed for the determination of fluorine ion in testing solution by adding the testing solution containing fluorine ion into standard solution of fluorine ion and was applied to the determination of fluorine ion concentration in AZ91D magnesium alloy microarc oxidation decay electrolyte. The interference ion and elimination method test indicated that,Zn2+、Cu2+、Ni2+ and Fe3+from magnesium alloy matrix into strongly alkaline micro-arc oxidation electrolyte could be removed in form of precipitae. The interference of Mg2+ and Al3+ could be eliminated using ionic strength reagent TISAB. The SiO32- and excessive Al3+ were masked with C4O6H2KNa and EDTA. OH-, Na+ and K+ in solution did not interfere in the determination of fluorine. The proposed method was applied to the determination of fluorine ion concentration in aged magnesium alloy micro-arc oxidation electrolyte with recoveries of 99.7 %-101.9 %. The fluorine ion concentration in microarc oxidation decay electrolyte of two magnesium alloy samples was determined by this method and ion selective electrodestandard curve method. The precision and accuracy of determination results were analyzed. It indicated that the precision of this method was better than that of ion selective electrodestandard curve method. The correctness of two methods was consistent. The proposed method could be applied to the direct determination of fluorine ion in complicated solution system containing fluorine ion mass concentration higher than 1.9 g/L.
马颖*,杨新龙,郝远. 离子选择性电极-逆格氏作图法测定镁合金微弧氧化衰变电解液中氟离子浓度[J]. 冶金分析, 2012, 32(5): 57-61.
MA Ying*,YANG Xin-long,HAO Yuan. Determination of fluorine ion concentration in magnesium alloy micro-arc oxidation decay electrolyte by ion selection electrode-reverse Gran graphics. , 2012, 32(5): 57-61.
