A KINETIC-STUDY OF THE THERMAL DEHYDRATION OF CALCIUM SULFITE HEMIHYDRATE

被引：10

作者：

ANDERSON, C

GALWEY, AK

机构：

[1] QUEENS UNIV BELFAST,SCH CHEM,BELFAST BT9 5AG,ANTRIM,NORTH IRELAND

[2] QUEENS UNIV BELFAST,CTR QUESTOR,BELFAST BT9 5AG,ANTRIM,NORTH IRELAND

来源：

CANADIAN JOURNAL OF CHEMISTRY-REVUE CANADIENNE DE CHIMIE | 1992年 / 70卷 / 09期

关键词：

D O I：

10.1139/v92-312

中图分类号：

O6 [化学];

学科分类号：

0703 ;

摘要：

An isothermal kinetic study of the dehydration of orthorhombic calcium sulphite hemihydrate is reported: CaSO3 . 1/2H2O(s) --> CaSO3(s) + 1/2H2O(g) Fractional reaction (alpha)-time curves exhibit the sigmoid shape characteristic of nucleation and growth reactions proceeding in the solid state. Yield-time data exhibit a very satisfactory obedience to the Avrami-Erofe'ev (n = 2) equation [-1n(1 - alpha)]1/2 = kt Rate studies were concerned with the temperature interval 573-673 K and the calculated activation energy was 173 8 kJ mol-1, showing the hydrate to be thermally relatively stable. The mechanism of dehydration is discussed and reference is made to the dehydration of calcium hydroxide with which it shows close similarities.

引用

页码：2468 / 2475

页数：8

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