论文部分内容阅读
本工作改进了希土-偶氮胂酸Ⅲ有色络合物的显色及其测定条件,提高了测定方法的灵敏度;用增加掩蔽剂磺基水杨酸和抗坏血酸的浓度的办法来提高干扰元素的允许量。从而拟定了不必经过分离而直接测定核纯石墨中痕量总希土的方法。此外,为了测定纯度较差的石墨中的总希土,亦研究了应用8-羟基喹啉-氯仿溶液萃取分离其他杂质的条件。此两种方法均较准确、快速,全部分析手续可在3—4小时内完成。控制试验表明,总希土的平均回收率分别为98%和93%。按取样量为1克计算,方法的测定下限为1×10~(-5)%。
This work improved the color of rare earth-arsenazoic acid Ⅲ colored complex and its determination conditions to improve the sensitivity of the determination method; with increased masking agent sulfosalicylic acid and ascorbic acid concentration to improve the interference elements The allowable amount. Thus, a method for direct determination of trace total rare earth in pure graphite without separation has been drawn up. In addition, in order to determine the purity of graphite in the total rare earth, also studied the use of 8-hydroxyquinoline - chloroform extraction of other impurities conditions. The two methods are more accurate and fast, all the analysis procedures can be completed within 3-4 hours. Control tests showed that the average recovery rate of total rare earth were 98% and 93% respectively. According to the sampling amount of 1 gram, the lower limit of the method is 1 × 10 ~ (-5)%.