流动注射化学发光法测定食品添加剂丙酸钙中铅和铬-化学(分析化学)专业论文.docxVIP

摘要本论义在文献的熬础上用流动渡射化学发光法测定以鸡激壳为原料制备的 摘要 本论义在文献的熬础上用流动渡射化学发光法测定以鸡激壳为原料制备的 食品添热剂覆酸钙中斡痰羹镪(II)和铬。 话(11)催纯过氧化氢氧仡番米诺和邻菲眵啉鹩亿学发光体系，发光强度与 铅(II)的浓度在一定瓶围内呈线蚀关系．但此体系不稳定。糟密度较差。程此 发光体系巾加入表嚣添性荆睦温．20，使体系稳定，穰密度较好；蔼且对体浆寿 增敏作用，使检测下限降低；氆使待测铅(11)液的p壬壬范溺由3拓宽至3～8， 对化学发光强度没有影响，方便了检测。用717烈强碱性阴离予氯型树脂吸附丙 酸钙中豹痰量镑(il)，与样晶中大羹静钙离子、少量豹等镁蒜子分开，然艨洗 脱被吸附酌锻(11)，掰上述纯学发光体系测定，络莱令人满意。 选用铬(m)催化道氧化氢氧化鲁米诺的化学发光体系检钡4痕量铬(Ⅵ)和 铬珏1)。用717型强碱性阴离子氯熬树I旨吸驸礞黢钙中的铬(Ⅵ)，面不吸附 铬(瑾)，使铬(硪)麓蓑俸分离，膈羧经过荤C纯筑还原洗脱梭吸附的铬(碱)， 铬(Ⅵ)被还原为铬(111)而从柱予上洗脱下来，用上述发光体系测定铬(IH)， 间接测定了丙酸钙中的锚(Ⅵ)；化学发光法测定铬(Ⅲ)对，由于样品丙黢锷 中存在的锈翔镁等离予对铬(戮)静铯学发光法灏定均产生予挽，量717塑滋碱 性阴离子氯型树脂只吸附铬(VI)，而不吸附铬(m)，故用谶硫酸铵将丙酸钙 中铬(磁)氧化成铬(Ⅵ)，再用上述同样方法鲶理、铡定舜黢钙中的铬(飘I) 盼含羹。淡脱褥驱上蔽辩豹铬(磙)遴常莠l抗舔搬羧和亚硫酸鬣镳溶液，毽：孝 在洗脱液中难以除去。干扰化学发光测定。本实黢用酸性过氧化氯作为还原洗脱 液，洗脱效果良好。过豢的过氧化甄疑加热分勰除去，避免了洗腻液中其它离子 辩纯学发党测定懿干扰。 关键词 流动注射 化学发光 鲁米诺 过裁化氢 铅 铬 丙酸钙 表嚣活性荆 In In this paper,the determinations of trace lead and chromium in calcium propionate synm韶ized from egg shell which acts a8 the food additives by using Flow inj∞tion chemiluminescence(FI·CL)are realized based on the literatures． Lead(II)sensitizes the weak CL induced by the oxidation of luminol with hydrogen peroxide in presence of l，10-phenanthroline．A linear relationship between CL intensity and the lead(II)concentration existed．However,the CL system is unstable and the determination precision is poor．In this work，surfactant Tween-20 w∞introduced in the above-mentioned CL system．n地obtained results showed that the system Was more stable and the sensitivity Was improved．Additionally the system Was enhanced and the detection precision Was good in the presence of Tween-20． Furthermore．the introducing of Tween-20 broadened the pH from 3 to 3～8 for the determination of lead(II)，which facilitated the detection．Trace lead(II)Was separated from the matrix and adsorbed by 717-strong basic chloric type anion-exchange resin,while plenty of calcium and magnesium cations co·existed in sample were not adsorbed by the resin．Salisfactory results were obtained when using t