新显色剂间甲酰基偶氮氯膦稀土胶敏络合物的吸光光度研究

新显色剂间甲酰基偶氮氯膦稀土胶敏络合物的吸光光度研究 SPECTROPHOTOMETRIC STUDY OF MICELLAR SENSITIZED COMPLEXES OF NEW COLOR REAGENT m-FORMYL CHLOROPHOSPHONAZO—RARE EARTHS-CETYL TRIMETHYL AMMONIUM BROMIDE 罗庆尧 first-author 史广昭 陈震华 张华山 曾云鹗 <正> 近年来,存阳离子表面活性物质存在下,稀土元素胶敏络合物的吸光光度法研究得到了迅速的发展。迄今为止,这类络合反应所用的螯合剂主要是含有多个羟基的三苯甲烷类染料,其优点是对比度大,灵敏度高,但反应酸度多偏碱性或中性,选择性不够理想。近年来发现某些变色酸双偶氮衍生物可以在较强酸度下与稀士元素形成胶敏络合物。反应的选择性和灵敏度均有所提高。我们合成的不对称变色酸双偶氮衍生物间甲酰基偶氮氯膦也具有这种性质。试剂的结构及名称如下: In a 0.1N hydrochloric acid medium, m-formyl chlorophosphonazo（m-FCP） sharp reacts with rare earths and cetyl trimethyl ammonium bromide（CTAB） in the presence of ethyl alcohol to form the blue-violet ternary association complexes. Their absorption maximum are at about 680nm. The contrast of the color reactions is about 120nm. The sensitivity is very high, under the experimental conditions the apparent molar absorptivity of cerium group rare earths（La, Ce, Pr, Nd）being（1.5-1.7）×10 5 mol -1 . cm -1 . Beer’s law is obeyed over 0--20 μg RE/25ml. The absorbance of complex was stable for at least 1.5 hours. As the result of the mole ratio method, slope ratio method and continuous variation method the composition of the complex is estimated to be 1:4（La:m--FCP）and 1:8（La:CTAB）. The micro-amount of cerium in a high-alloy steel was determined by this method. 1982-02-01 2021-04-01 2