Determination of the Acid-Base Dissociation Constant of Acid-Degradable Hexamethylenetetramine by Capillary Zone Electrophoresis

• TAKAYANAGI Toshio

  Graduate School of Science and Technology, Tokushima University

• SHIMAKAMI Natsumi

  Graduate School of Advanced Technology and Science, Tokushima University

• KURASHINA Masashi

  Graduate School of Science and Technology, Tokushima University

• MIZUGUCHI Hitoshi

  Graduate School of Science and Technology, Tokushima University

• YABUTANI Tomoki

  Paper Industry Innovation Center, Ehime University

Abstract

The acid-base equilibrium of hexamethylenetetramine (hexamine) was analyzed with its effective electrophoretic mobility by capillary zone electrophoresis. Although hexamine is degradable in a weakly acidic aqueous solution, and the degraded products of ammonia and formaldehyde can be formed, the effective electrophoretic mobility of hexamine was measured in the pH range between 2.8 and 6.9. An acid-base dissociation equilibrium of the protonated hexamine was analyzed based on the mobility change, and an acid dissociation constant of pK_a = 4.93 ± 0.01 (mean ± standard error, ionic strength: 0.020 mol dm^–3) was determined. The monoprotic acid-base equilibrium of hexamine was confirmed through comparisons of its electrophoretic mobility with the N-ethylquinolinium ion and with the monocationic N-ethyl derivative of hexamine, as well as a slope analysis of the dissociation equilibrium.

Journal

• Analytical Sciences

  Analytical Sciences 32 (12), 1327-1332, 2016

  The Japan Society for Analytical Chemistry

Keywords

• Hexamethylenetetramine
• acid-base equilibrium
• capillary zone electrophoresis
• acid degradation

Details

• CRID: 1390001204259841664
• NII Article ID: 130005433404
• NII Book ID: AA10500785
• DOI: 10.2116/analsci.32.1327
• ISSN: 13482246
• ISSN: 09106340
• NDL BIB ID: 027778666
• PubMed: 27941263
• Web Site: https://repo.lib.tokushima-u.ac.jp/114221
• Web Site: https://ndlsearch.ndl.go.jp/books/R000000004-I027778666
• Web Site: https://link.springer.com/content/pdf/10.2116/analsci.32.1327.pdf
• Web Site: https://link.springer.com/article/10.2116/analsci.32.1327/fulltext.html
• Web Site: https://www.jstage.jst.go.jp/article/analsci/32/12/32_1327/_pdf
• Text Lang: en
• Data Source:
  • JaLC
  • IRDB
  • NDL
  • Crossref
  • PubMed
  • CiNii Articles
  • KAKEN
• Abstract License Flag: Disallowed