|
|
|
| Development Purifying Device for CRM of Benzoic Based on Zone Melting |
| SUN Guo-hua, LI Jia, WU Bing, WANG Hai-feng, MENG Fan-min |
| National Institute of Metrology, Beijing 100013, China |
|
|
|
|
Abstract The purifying device based on zone melting designed by the National Institute of Metrology (NIM) is described. The calorific primary reference material of benzoic is purified by the device. For improving the quality of highly purified sample,a new design of twin heater is employed. The crackle of glass tube due to inner tension is avoided by the new design of angle controller which can increase cross sectional area. The purity of benzoic is determined by the national primary standard instrument of coulometry. The result of benzoic purified by the device is 99.999%,which expanded uncertainty is 0.016 %(k=2). It proves the device meet the primary reference material requirements of purification.
|
|
|
|
|
|
[1] 孟凡敏,孙国华,李佳.国家燃烧热基准的技术改造[J].化学分析计量,2004,13(6):83-85.
[2] 孟凡敏,孙国华,李佳. 国家燃烧热基准技术改造研究报告[R].中国计量科学研究院,2006.
[3] Pfann W G. 区域熔化[M]. 刘民治,译. 北京:科学出版社,1962.
[4] Pal N L. 区域提纯及有关技术[M]. 李华昌,黄正荣,译. 上海:上海科学技术出版社,1963.
[5] 李佳,孙国华,王海峰,等.绝对法测量燃烧热标准物质苯甲酸的国际比对研究[J].计量学报,2010,31(5A):151-153.
[6] Friedenberg R,Jannke P J,Hilding W. Theoretical considerations in the zone melting of organic substances: Analysis of the diffusion gradient[J].Talanta,1966,13(2):245-263.
[7] 吴鑫干,陈舒伐. 苯甲酸的合成和精制[J].现代化工,2000,20(8):10-14.
[8] Ma L. Determination of the purity of potassium iodate by constant-current coulometry[J]. Accreditation and Quality Assurance,2002,7(4):163-167.
[9] 吴冰,马联弟. 基准试剂纯度国家基准技术改造研究报告[R]. 中国计量科学研究院,2010. |
|
|
|
2014, Vol. 35 
