The effect of procedural variables on TG, DTG and DTA curves of calcium carbonate

TLDR: The effect of procedural variables, including sample mass, heating rate, particle size and partial pressure of carbon dioxide, on TG, DTG and DTA curves for the decomposition of A R calcium carbonate and limestone has been studied as discussed by the authors.

Abstract: The effect of procedural variables, including sample mass, heating rate, particle size and partial pressure of carbon dioxide, on TG, DTG and DTA curves for the decomposition of A R calcium carbonate and limestone has been studied Such variables have a marked effect, similar in magnitude for both DTG and DTA The effect of sample mass, or depth of undiluted sample, is shown to be due to an increase in the partial pressure of carbon dioxide within the reacting powder and has been called the bed-depth effect This effect is most pronounced in nitrogen but is much reduced in carbon dioxide Inert diluents have little effect on the TG curves but changing the composition of the inert carrier gas causes variations which are correlated with the thermal conductivity of the gas Water vapour causes a lowering of the DTG and DTA peak temperatures