FLASH DEHYDRATION OF ULEXITE AND INVESTIGATION OF DEHYDRATION KINETICS FROM THERMOGRAVIMETRIC DATA

ERSAHAN H., TUNC M., EKMEKYAPAR A., YAPICI S.

THERMOCHIMICA ACTA, vol.250, no.1, pp.125-135, 1995 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 250 Issue: 1
  • Publication Date: 1995
  • Doi Number: 10.1016/0040-6031(94)01978-p
  • Journal Name: THERMOCHIMICA ACTA
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.125-135
  • Inonu University Affiliated: Yes

Abstract

The flash dehydration of a ulexite mineral in an entrained flow reactor was investigated. Flash dehydration experiments were carried out in the range 400-700 degrees C with material of particle size -425+300 mu m. The weight loss at 700 degrees C dehydration temperature was measured as 22%. A thermal gravimetric method was used to obtain the activation energy and rate constants for the dehydration of ulexite. The activation energy was in the range 48.2-53 kJ mol(-1) for different particle sizes. The rate constants for different particle sizes were found to vary between 1.8 x 10(-4) and 1.35 s(-1) in the temperature range 110-530 degrees C.