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YW_1合金成份是W、Ti、Nb,目前测钛广泛采用的是铝片还原法,本法有W、V、Cr、Sn、Sb、Mo、Ag、Nb)等元素干扰。在YW_1合金中,钨可在用氢氧化钠中和沉淀钛时得以分离,而铌却形成铌酸和钛一起沉淀而干扰。因为铌的低价态不太稳定,不一定定量与Fe~(3+)作用,无法扣除,靠加入草酸来掩蔽,效果不好,也有人用氢氧化钾沉淀钛以排除铌的干扰,但效果不理想。本法基于Nb(+5)/Nb~(+3)(-0.34伏)与Fe~(2+)/Fe(-0.44伏)很接近,在强酸介质中,可用铁粉还原钛,Nb就不被还原而达到分离。其次溶液中存在大量Fe~(2+)而使Ti~(3+)被空气氧化的速度减缓,可减少加入硫酸铵的量。此法用于YW_1合金中钛(含钛7～25%)的测定效果很好。
YW_1 alloy composition is W, Ti, Nb, the current titanium is widely used aluminum reduction method, the law W, V, Cr, Sn, Sb, Mo, Ag, Nb) and other elements of interference. In the YW-1 alloy, tungsten can be separated while neutralizing precipitated titanium with sodium hydroxide, whereas niobium interferes with the precipitation of niobic acid and titanium. Because the low valence state of niobium is not very stable, it is not necessarily quantified as Fe 3+ and can not be deducted. However, if oxalic acid is used to mask it, the effect is not good. Some people use titanium hydroxide to precipitate titanium to eliminate the interference of niobium. The effect is not satisfactory. This method is based on the close relationship between Nb (+5) / Nb ~ (+3) (-0.34 volts) and Fe2 + / Fe (-0.44 volts). In strong acid medium, Not be restored to achieve separation. Secondly, there is a large amount of Fe2 + in the solution and the Ti3 + is oxidized by the air, so that the amount of ammonium sulfate can be reduced. This method is used for YW_1 alloy titanium (containing 7 ~ 25% titanium) determination of good effect.