摘要
In pH 2.0-3.0 medium,niobium(v)forms molybdoniobic acid with sodium molybdate.A spectrophotometric method has been developed for the determination of niobium based on the formation of ion-associate compound of molybdoniobate with butyl Rhodamine B in aqueous solution in the presence of polyvinyl alcohol and 0.4-0.7 mol/L H_2SO_4.The molar absorptivity is 7.5×10~5 L.mol^(-1).cm^(-1) for niobium at 585 nm.
In pH 2.0-3.0 medium,niobium(v)forms molybdoniobic acid with sodium molybdate.A spectrophotometric method has been developed for the determination of niobium based on the formation of ion-associate compound of molybdoniobate with butyl Rhodamine B in aqueous solution in the presence of polyvinyl alcohol and 0.4-0.7 mol/L H_2SO_4.The molar absorptivity is 7.5×10~5 L.mol^(-1).cm^(-1) for niobium at 585 nm.
