水酸化物分離,酢酸アミル抽出,Oxineによる比色
鉄鋼中のセリウムの定量法-II
1958 年 44 巻 7 号 p. 762-767
詳細
1958 年 44 巻 7 号 p. 762-767
In the first paper, the authors reported Knorr'es method could be applied to determine Ce in the steel treated with Misch-metal added. In Knorre's method, however 1m. gr. is the utmost limit to determinable Ce amounts, and it needs to get 5grs as sample from the steel containing 0.03%. Ce. If weights of sample from high grade stainless steel will reach to 5 grs., it will be very difficult to dissolve in sulphric acid solution and will be needed a long time to electrolyze. Investigatin, therefore, must be taken about colorimetry by which sample is enough of relatively small amounts and micro contents of Ce can be determined.
About micro contents of Ce in stainless steel added Misch-metal during melting period, the authors carried out colorimetric determination with separating as follows:
(i) All rare earth metals were separated as oxide by HF as reported in first paper.
(ii) Oxide was dissolved with acid solution, then hydroxide precipitated, from which Ce(OH)4 was separated with difference of PH and. CeO2 was produced by heating.<Br>(iii) CeO2 was dissolved again with acid solution, then pure CeO2 was produced by HF separating.
iv) Pure CeO2 was dissolved with acid solution, extracted with amyle acetate, then carried out colorimetric determination with oxine.
