2022 Volume 15 Issue 2 Pages 123-130
A thermal lag in reaction calorimeters could cause an underestimation of the rate of heat generation. Therefore, investigating the correction method used to estimate the thermal lag is essential. In general, a controlled heat source and time constants are the variable parameters used to estimate the correction. This paper reports an improved correction method for estimating the thermal lag in reaction calorimeters using heat pulses and higher-order time constants. It was observed that thermal lags occurred when the sample vessels containing water were exposed to heat pulses. Our studies revealed that the accuracy of the correction improved with an increase in the order of time constants. The effect of the position of the heat source on the higher-order time constants was determined. It was observed that the heat sources, when located outside the sample vessels, contributed to the underestimation of the heat generation rate due to the lack of correction of thermal lags in the sample vessel. For heat generation by the dissolution of sodium hydroxide, changing the position of the heat source yielded widely different heat generation rates, thereby proving that a suboptimal placement of the heat source led to an underestimation of thermal hazards.
