Study on Bridge Formation Mechanism between NaCl Crystals and Functions of Anti-caking Agents

DOI Web Site 17 References
  • Mineo Hayato
    Department of Applied Chemistry, Graduate School of Science and Engineering, Chuo University
  • Saito Yuiko
    Department of Applied Chemistry, Faculty of Science and Engineering, Chuo University
  • Ohno Ayako
    Department of Applied Chemistry, Faculty of Science and Engineering, Chuo University
  • Nakamura Kazumasa
    Department of Applied Chemistry, Faculty of Science and Engineering, Chuo University
  • Shindo Hitoshi
    Department of Applied Chemistry, Graduate School of Science and Engineering, Chuo University Department of Applied Chemistry, Faculty of Science and Engineering, Chuo University

Bibliographic Information

Other Title
  • NaCl結晶間架橋のメカニズムと固結防止剤の作用
  • NaCl ケッショウ カン カキョウ ノ メカニズム ト コケツ ボウシザイ ノ サヨウ

Search this article

Description

As a model for the caking of salt particles, bridge formation processes between NaCl single crystals were observed using optical microscopy. Starting with a liquid bridge of NaCl aq. connecting two crystal plates, NaCl crystal growth was observed during the evaporation of water at room temperature, both on the liquid surface and at three-phase boundaries on the substrates. In a rare case, under lower relative humidity (32%), small crystals formed on the liquid surface connected with one another, forming a tubular solid bridge. In most cases, however, the crystal growth occurred mainly at the three-phase boundaries on the substrates. The crystals grew along the liquid surface, finally forming a tubular solid bridge. The bridge contained a substantial amount of solution inside, which later caused efflorescence growth along the contact line of the tubes grown from both sides. In low temperature experiments at –10°C with the same experimental setup, growth of NaCl·2H2O crystals were observed in the solution. A mechanism for low temperature caking due to the crystal formation. With the addition of K4 [Fe(CN)6], an anti-caking agent, at room temperature, lots of pores were formed on the tubular wall of the NaCl bridge. Due to stabilization of {120} faces, the growth front of the wall most probably took a rugged shape, resulting in the formation of a fragile bridge. The functions of other anti-caking agents, namely, the water-retaining effect of CaCl2 and isolation effect of basic magnesium carbonate, were also studied.

Journal

References(17)*help

See more

Related Projects

See more

Keywords

Details 詳細情報について

Report a problem

Back to top