TiCl3 slurry is a vanadium removal reagent in the process of removing vanadium from crude titanium aluminum tetrachloride powder, among which AlCl3 plays a catalytic role and is one of the key factors affecting the quality of vanadium removal reagent. TiCl3 slurry is a kind of purplish red solution, which also contains Fe3+, Fe2+, V3+, V5+ and other colored metal ions. If AlCl3 is measured by conventional complexometric titration or spectrophotometry, these non-ferrous metal ions will cause serious interference, and it is difficult to accurately judge the end point of titration. In the experiment, the co-existing ions such as Ti4+, V5+ and Fe3+ in the sample solution were removed by hydroxide precipitation method, and Al in the sample solution was determined by NH4F displacement titration method. The effect of solution pH on separation results of coexisting ions was investigated. The experimental conditions including titration method, indicator and displacer were obtained. The interference tests of coexisting ions showed that the coexisting ions in solution had no influence on the determination when the relative error of measurement results was controlled within ±2.0%. The proposed method was applied for the determination of AlCl3 in TiCl3 slurry. The relative standard deviation (RSD, n=8) was less than 3.0%. The recoveries were between 96% and 102%. This method effectively solved the determination of Al in complex matrix. Meanwhile, it could also provide a reference for the composition analysis in other similar samples with complex matrix.
MIAO Qing-dong,LI Kai-hua,HE An-xi,et al.Preparation and application of TiCl3 slurry used in Al-Powder vanadium removal of crude TiCl4[J]. Chinese Journal of Rare Metals,2017,41(12):1369-1373.
LI Liang,LI Kai-hua,MIAO Qing-dong,et al.Preparation and application of vanadium removing reagent in refining crude TiCl4[J].Chinese Journal of Rare Metals,2015,39(7):666-671.
MIAO Qing-dong,LI Kai-hua,CHEN Ai-xiang.Effect of dissolved Cl2 in crude TiCl4 on vanadium removal by aluminum powder[J].Iron Steel Vanadium Titanium,2018,39(2):14-18,31.
CHEN Rui,LIU Yang,SUN Ya-li.Determination of trace aluminum in titanium tetachloridy by aluminium-chrome azurol (S)-ctmab spectrophotometry[J].Chemical Analysis and Meterage,2008,17(5):60-62.
ZHANG Tian-jiao.Determination of aluminum oxide in cobalt-chromium-aluminum-yttrium-tantalum coating by mechanical peeling-EDTA titrimetry[J].Metallurgical Analysis,2016,36(6):13-17.
SONG Guang-lin,GUO Peng-ran,LI Jin-qing,et al.Determination of trichloroacetyl chloride in refine titanium tetrachloride by acid hydrolysis and ion chromatography[J].Chinese Journal of Analytical Chemistry,2015,43(6):909-913.