CuSO4 chromogenic tracing for migration and crystallization of salt solution in porous materials

The migration and crystallization of CuSO 4 solution characterized by color change property on the surface of glass of hydrophobic property, capillaries and porous resin materials were observed online in real time. The research results indicated that under the condition of stable environment, crystals generated by CuSO 4 droplets were relatively complete, and crystals would also easily be accumulated both inside and outside of the capillaries, in particularly, the crystal morphology inside the capillaries altered along with the change of solution state. Meanwhile, there were parabolic migration and crystallization of the salt solution in the porous material samples, and the samples with saturated salt solution had a wide range of crystal areas when the salt solution had been completely crystallized in the porous samples, while the crystal belt in the interior samples was produced with less salt solution. In this paper, the parabola with opposite direction in the process of salt solution migration and crystallization, as well as the distribution of whitespace and crystal belt were found for the first time.