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高速钢中锰含量较低,而铬量较高,同时含有大量的钨,要想用连续容量法进行锰铬钒的测定是有一定困难的。我们采用硫磷混酸溶样后,以高氯酸加热冒烟氧化,锰铬钒分别被氧化为三、六、五价,以二苯胺磺酸钠为指示剂,用亚铁溶液滴定锰铬钒总量。然后补加磷酸,加热冒烟并驱尽高氯酸,此时大部分铬又成三价状态,而只是锰钒被氧化,继加亚砷酸钠还原部分高价铬,再以亚铁溶液滴定锰钒合量。最后于室温下用高锰酸钾氧化钒,测得钒量,并用差减法求得
High-speed steel in the lower manganese content, while the higher chromium content, while containing a lot of tungsten, in order to use continuous volume method for the determination of manganese chromium vanadium is a certain difficulty. We use phosphoric acid mixed acid sample, the perchloric acid heating smoke oxidation, manganese chromium vanadium were oxidized to three, six, five price, with sodium diphenylamine sulfonate as indicator, with ferrous solution titration manganese chrome vanadium Total amount. Then add phosphoric acid, heat smoke and drive perchlorate, most of the chromium into the trivalent state, but only manganese and vanadium is oxidized, followed by sodium arsenite reduction part of the high price of chromium, and then ferrous solution titration Manganese vanadium content. Finally, at room temperature with potassium permanganate vanadium oxide, vanadium measured, and calculated by subtraction