采用基于BET吸附理论的静态容量法测定硬脂酸镁比表面积
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摘要
以氮气为吸附质,采用基于BET吸附理论的静态容量法测定硬脂酸镁的比表面积。由于在生产、处理和贮存过程中,硬脂酸镁表面会吸附一些其他气体或蒸汽,导致测定结果有波动。因此在测定前应进行加热和脱气预处理。分别考察了加热温度、取样量和减压时间等预处理条件对硬脂酸镁比表面积测定结果的影响,确定本法测定脂酸镁的预处理条件为:加热温度75℃,取样量3 g,减压处理2 h。本法的重现性和耐用性试验结果均较好。测得3批硬脂酸镁的比表面积均值分别为3.743、4.014和3.857 m~2/g,RSD分别为2.9%、3.0%和2.5%(n=5)。
The specific surface area of magnesium stearate was determined by static volumetric method based on BET adsorption theory with nitrogen as the adsorbate. During manufacture, processing and storage, some gases or vapours could be adsorbed by magnesium stearate, which caused fluctuations of determination results. As a result, the samples should be pretreated by heating and degassing before determination. The effects of pretreatment conditions, such as heating temperature, sampling amount and evacuation time on the determination results of specific surface area were investigated. The results showed that the optimal conditions were as follows: 3 g of magnesium stearate was heated at 75 ℃ and evacuated for 2 h. The method had good reproducibility and durability. The specific surface areas of three batches of magnesium stearate were 3.743, 4.014 and 3.857 m~2/g with RSDs of 2.9%, 3.0% and 2.5%(n=5), respectively.
The specific surface area of magnesium stearate was determined by static volumetric method based on BET adsorption theory with nitrogen as the adsorbate. During manufacture, processing and storage, some gases or vapours could be adsorbed by magnesium stearate, which caused fluctuations of determination results. As a result, the samples should be pretreated by heating and degassing before determination. The effects of pretreatment conditions, such as heating temperature, sampling amount and evacuation time on the determination results of specific surface area were investigated. The results showed that the optimal conditions were as follows: 3 g of magnesium stearate was heated at 75 ℃ and evacuated for 2 h. The method had good reproducibility and durability. The specific surface areas of three batches of magnesium stearate were 3.743, 4.014 and 3.857 m~2/g with RSDs of 2.9%, 3.0% and 2.5%(n=5), respectively.
引文
[1]Rowe RC,Sheskey PJ.药用辅料手册[M].郑俊民,译.4版,北京:化学工业出版社,2005:407—410.
[2]王涛,张铭辉,殷光玲.几种直压辅料的可压性及其对硬脂酸镁的敏感性[J].今日药学,2014,24(2):99—101.
[3]郭仁庭,覃忠富,傅长明,等.硬脂酸镁的性质、应用及市场前景综述[J].企业科技与发展,2011,(7):15—17.
[4]柳翱,巴晓微,刘颖,等.BET容量法测定固体比表面积[J].长春工业大学学报:自然科学版,2012,33(2):197—199.
[5]宋军,王鉴,汪丽,等.容量法测定载体活性炭的比表面积[J].化学工程,2011,39(10):19—21.
[2]王涛,张铭辉,殷光玲.几种直压辅料的可压性及其对硬脂酸镁的敏感性[J].今日药学,2014,24(2):99—101.
[3]郭仁庭,覃忠富,傅长明,等.硬脂酸镁的性质、应用及市场前景综述[J].企业科技与发展,2011,(7):15—17.
[4]柳翱,巴晓微,刘颖,等.BET容量法测定固体比表面积[J].长春工业大学学报:自然科学版,2012,33(2):197—199.
[5]宋军,王鉴,汪丽,等.容量法测定载体活性炭的比表面积[J].化学工程,2011,39(10):19—21.