Abstract
Water content in solid materials is usually measured by loss on drying and Karl Fischer titration (KFT) methods. The validation of KFT methods requires the certified reference materials (CRMs) for the water content in solids, especially those with lower water content. In the present study, two mixtures of sodium tartrate dihydrate and 4-methoxybenzoic acid were prepared using the gravimetric method and then used as candidates of CRMs with water content of 10.0 and 1.0 mg·g−1, respectively. Furthermore, the CRM of lactose monohydrate and that of 4-methoxybenzoic acid were also developed. The stability against the humidity of the raw materials was characterized using water sorption isotherms. The thermal stability of the raw materials was characterized by the thermogravimetric analyzer. These four CRMs for water content were certified using Karl Fischer coulometric and volumetric titration. To make the water content traceable, both KFT methods were calibrated using a home-made water content standard prepared by the gravimetric method. The average value of the two methods was used as the certified value. The certified water contents and their expanded uncertainties (U, k = 2) of four CRMs were (50.7 ± 0.6) mg·g−1, (9.90 ± 0.2) mg·g−1, (0.878 ± 0.044) mg·g−1 and (0.142 ± 0.013) mg·g−1, respectively. This series of CRMs were suitable for the validation of KFT methods for the water contents in solids.
Similar content being viewed by others
References
M. Butt, M. Nasir, S. Akhtar, K. Sharif, Internet J. Food Saf. 4, 1 (2004)
L. Frink, C. Weatherly, D. Armstrong, J. Pharm. Biomed. Anal. 94, 111 (2014)
C. Skaar, Wood-water relations (Springer-Verlag, Berlin Heidelberg, 1988)
ISO 1928–2009, Solid mineral fuels—determination of gross calorific value by the bomb calorimetric method and calculation of net calorific value (ISO, Geneva, 2009)
K. Ishikawa, N. Hanari, Y. Shimizu, T. Ihara, A. Nomura, M. Numata, T. Yarita, K. Kato, K. Chiba, Accred Qual. Assur. 16, 311 (2011)
P. Miao, S.A. Bell, M. Rujan, M. Georgescu, C. McIlroy, Report on literature review of recent development in loss on drying method for moisture determination, NPL REPORT ENG 52, March 2014
E. Scholz, Karl Fischer Titration (Springer Verlag, Heidalberg, 1984)
W. Fetzer, Anal. Chem. 23, 1062 (1951)
W. Whalley, T. Dean, P. Izzard, J. Agr. Eng. Res. 52, 147 (1992)
T. Williams, J. Hydrol. 46, 385 (1980)
C. Corredor, D. Bu, D. Both, Anal. Chim. Acta 696, 84 (2011)
S. Bell, P. Miao, P. Carroll, Int. J. Thermophys. 39, 50 (2018)
W. Lück, Feuchtigkeit (R. Oldenbourg Verlag, Munich, 1964)
S. Bell, P. Miao, P. Carroll, New reference materials for calibration of moisture analysers, (2016). https://www.dropbox.com/sh/yixc7iusk8qad2k/AABkr2SwqZHWOUC4zVQaQlJja/Workshop%20Taastrup?dl=0&preview=02+-+S+Bell+New+reference+materials+20160510.pdf&subfolder_nav_tracking=1
W. Liu, H. Wang, X. Gu, C. Quan, X. Dai, Anal. Methods 8, 2845 (2016)
M. Medvedevskikh, A. Sergeeva, M. Krasheninina, O. Shokhina, Measur. Tech. 62, 475 (2019)
ISO Guide 35, Reference materials-general and statistical principles for certification (ISO, Geneva, 2006)
H. Wang, K. Ma, W. Zhang, T. Huang, X. Dai, J. Li, G. Sun, H. Li, Accred Qual. Assur. 17, 589 (2012)
S. Margolis, M. Levenson, Fresenius J. Anal. Chem. 367, 1 (2000)
S. Inagaki, M. Numata, Y. Kitamaki, N. Hanari, R. Iwasawa, Accred Qual. Assur. 21, 361 (2016)
H. Wang, K. Ma, W. Zhang, J. Li, G. Sun, H. Li, Food Chem. 134, 2362 (2012)
Acknowledgments
This study was supported by the National Quality Infrastructure Program of China (No. 2017YFF0205300) and the Ability Promotion Program of the National Institute of Metrology of China (No. 31-ANL1814).
Author information
Authors and Affiliations
Corresponding author
Additional information
Publisher's Note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Selected Papers of the 14th International Symposium on Temperature and Thermal Measurements in Industry and Science.
Rights and permissions
About this article
Cite this article
Zhi, X., Wang, H., Wu, Z. et al. Development of Four Certified Reference Materials for Water Content in Solids. Int J Thermophys 41, 50 (2020). https://doi.org/10.1007/s10765-020-02634-7
Received:
Accepted:
Published:
DOI: https://doi.org/10.1007/s10765-020-02634-7