Assessment of propionic acid adsorption performance on the phase transformation of calcium sulfate hemihydrate to dihydrate

Polat S. , Sayan P.

SEPARATION SCIENCE AND TECHNOLOGY, cilt.53, ss.1966-1978, 2018 (SCI İndekslerine Giren Dergi) identifier

  • Cilt numarası: 53
  • Basım Tarihi: 2018
  • Doi Numarası: 10.1080/01496395.2018.1442862
  • Sayfa Sayıları: ss.1966-1978


The adsorption of propionic acid during the transformation process of calcium sulfate hemihydrate to calcium sulfate dihydrate was studied in a batch-type crystallizer with respect to contact time, additive concentration and temperature in pure media, and in the presence of propionic acid used as an additive. The adsorbent was characterized by X-ray diffraction, scanning electron microscopy and thermogravimetric analysis combined with a Fourier-transform infrared spectrometer and a mass spectrometer. The adsorption characteristics were also investigated by means of evaluating the isotherm, kinetic and thermodynamic properties. The results of this investigation showed that propionic acid can serve as a good accelerator for the transformation process from calcium sulfate hemihydrate to dihydrate.