【摘要】 在水—乙醇介质中,稀土与偶氮胂Ⅲ在pH为1.2～2.1的酸度范围内可形成1∶2的紫红色络合物,摩尔吸光系数高达8.2×10⁴l·mol·cm^-1,含稀土总量为0～50μg/25ml范围内服从比尔定律。铁的干扰采用EDTA掩蔽,避免了复杂的分离手续。该方法具有较高的灵敏度,选择性、重现性良好,用于稀土硅镁合金中稀土总量的测定,分析结果满意,已用于生产。更多还原

【Abstract】 A rapid sensitive and selective spectrophotometric method for the determination of total amount of the rare earth elements in the ferroalloy of containing rare earth silicon and magnesium has been developed. A purplish red complex which has ratio of RE to Arsenazo-Ⅲ to be 1:2 can be formed in the range of pH 1.2-2.1 in the ethanol aqueous solution (λmax=648nm,λ648 = 8.2×041 mol-1cm-1). Beer’s law is obeyed in the concentration range of 0 to 50μg/25ml.The interference of Fe(Ⅲ) can be covered with EDTA.更多还原