浅议《石墨化学分析方法(GB/T 3521-2008)》

A discussion on the 2008 edition of "standard" method for chemical analysis of graphite

对2008版《石墨化学分析方法》标准与1995版进行了比较,分析了新版标准在技术要求与指标上的变化。同时结合工作实践,对标准中关于挥发分、灰分及硫含量的测试要求提出了自己的一些见解,希望引起同行的关注。建议:①进行挥发分测试时,将装载试样的敞口石英舟改为带盖的石英坩埚;②进行高纯石墨试样灰分测试时可通过适当加大称样量的方式来提高测试结果的精确度和可靠性。同时,按样品灰分的不同对灰分平行测定结果的绝对误差允许值范围进行细化;③进行硫含量测试时,将炉温升至1 400～1 450℃,根据样品中硫含量范围选择不同浓度的碘酸钾标准溶液,测高、低硫样品的燃烧管分别使用。同时,按样品硫含量的不同对硫含量平行测定结果的绝对误差允许值范围进行细化。

The 2008 edition of ＂standard＂ method for chemical analysis of graphite and the 1995 edition are compared, and the technical requirements and index of changes in the new standard are analyzed. Combined with the work practice, opinions of the test requirements for volatile matter, ash and sulfur content are proposed. Suggestions include： ① Take a cover to the sample container, such as quartz crucible, when taking a volatile test. ② To high pure graphite sample, appropriately increase the sample weight to improve the accuracy and reliability of the ash content test result. At the same time, the allowed values of the absolute error range of the parallel determination results of ash content should be further partitioned. ③To sulfur content test, increase the temperature from 1400 ℃ to 1450 %, and select standard solution of potassium iodate with different concentration according to the sulfur content of the sample. Combustion tubes for samples with different sulphur content should be used separately. At the same time, the allowed values of the absolute error range of the parallel determination results of sulfur content should be further partitioned.