以聚乙二醇 -硫酸铵 -铝试剂体系萃取分离干扰离子 ,采用铬天青S -溴化十六烷基三甲胺为显色体系测定重油中的铁。考查了萃取分离的条件和测定条件。人工合成样品回收率为 98 8%～ 1 0 4 2 % ,配合物最大吸收波长位于 675nm ,表观摩尔吸收系数为 7 78× 1 0 4 L/(mol·cm) ,Fe3+ 量在 0～ 5μg/2 5ml内服从比尔定律。方法简单 ,可靠 ,并且整个萃取操作具有安全、无毒、快速的特点。 The interference ions were extracted and extracted by polyethylene glycol - ammonium sulfate - aluminum reagent system, and the determination of iron in heavy oil was carried out by using chromocyanin S - cetyltrimethyl ammonium bromide as chromogenic system. Examined the extraction conditions and determination conditions. The recovery rate of artificial synthetic samples was 98 8% ~ 1 0 4 2%, the maximum absorption wavelength of the complex was at 675 nm, the apparent molar absorption coefficient was 7 78 × 10 4 L / (mol · cm), the amount of Fe 3 + was 0 ~ 5 μg / 2 5ml Oral obey Bill’s law. The method is simple and reliable, and the whole extraction operation is safe, non-toxic and rapid.