| Autor: |
Takaizumi, Katsuko |
| Zdroj: |
Journal of Solution Chemistry; May 2005, Vol. 34 Issue: 5 p597-612, 16p |
| Abstrakt: |
Abstract The freezing–thawing process of aqueous ethanol solutions has been studied by differential scanning calorimetry (DSC) in an intermediate concentration range higher than about 30 wt% of the alcohol. Two kinds of ethanol hydrate solid were confirmed to exist: EtOH⋅4.67H2O with a melting peak (D1∗) at −64.5∘C and EtOH⋅4.75H2O with a melting peak (D2∗) at −63.1∘C. The peak D1∗ appears just after mixing ethanol and water. However, the peak curiously shifts to the D2∗ peak after storage for a few days or more at room temperature. The phenomenon was accelerated by heating or by repetition of the freezing–thawing process. The origin of the phenomenon has been discussed in relation to the state of solution. |
| Databáze: |
Supplemental Index |
| Externí odkaz: |
|
Full text from SpringerLink