NIOSHTIC-2 Publications Search

Dolomite for determining atmosphere control in thermal analysis.

Authors
Smith-JW; Johnson-DR; Muller-Vonmoos-M
Source
Thermochim Acta 1974 Jan-Feb; 8(1-2):45-56
NIOSHTIC No.
10010795
Abstract
A generally applicable test using dolomite to detect effects of atmosphere self-generation and to determine atmosphere control in thermal analysis is demonstrated. Either differential thermal analysis (DTA) or thermogravimetry (TG) can be used. In a CO2 atmosphere dolomite produces two separate thermal decompositions, but in a CO2-free atmosphere dolomite decomposes in a single reaction. If two peaks or a shoulder appear on the decomposition response in air, effects of self-generated CO2 are proven. If the reaction in air is not complete by 800 degrees C, self-generated CO2 around the sample is strongly indicated. The dolomite decomposition at lower temperature in CO2 essentially independent of CO2 pressure, can be used to establish a temperature reference point for this atmosphere testing. Thin layers of sample and a gas stream flowing over the sample are shown to be necessary for atmosphere control in thermal analysis.
Keywords
Thermal-effects; Thermal-reactions; Gases
CODEN
THACAS
CAS No.
124-38-9
Publication Date
19740101
Document Type
OP; Journal Article
Fiscal Year
1974
Identifying No.
OP 54-74
Issue of Publication
1-2
ISSN
0040-6031
NIOSH Division
LERC
Source Name
Thermochimica Acta
State
WY
Page last reviewed: March 11, 2019
Content source: National Institute for Occupational Safety and Health Education and Information Division