Accelerating rate calorimeter, reactive

Accelerating rate calorimeters (ARC) are customarily used to determine the overall reactivity of compounds. One limitation of these instruments is that pressure data at pre-exotherm temperatures are not recorded. However, such information may be important for the analysis of reactive systems in which pressure events are observed prior to the exotherm. An ARC has been modified so that pressure data can be acquired and stored for kinetic analysis by interfacing with a personal computer. Results are presented using this technique for the study of the decomposition chemistry of 4,4 -diisocyanatodiphenylmethane (MDI). 

Several commercial calorimeters are available to characterize runaway reactions. These include the accelerating rate calorimeter (ARC), the reactive system screening tool (RSST), the automatic pressure-tracking adiabatic calorimeter (APTAC), and the vent sizing package (VSP). Each calorimeter has a different sample size, container design, data acquisition hardware, and data sensitivity. 

ARC = Accelerating Rate Calorimeter (Columbia Scientific Instrument Corp.) DSC = Differential Scanning Calorimeter DTA = Differential Thermal Analysis RC1 = Reactor Calorimeter (Mettler-Toledo Inc.) RSST = Reactive System Screening Tool (Fauske and Associates) VSP = Vent Size Package (Fauske and Associates) ... 

Peroxide compounds are usually very reactive and flanunable. They have caused many catastrophic accidents around the world because of their reactive potential. Conventional methods to assess risk of such a reactive chemical have been done by experiments with precision machine such as DSC (differential scanning calorimeter), ARC (accelerating rate calorimeter), etc., but they need more finance, concentration and charge of danger. To overcome that, computer aided prediction method using group contribution method was used in this study. Some essential thermodynamic properties of chemicals were evaluated by this method, and then adiabatic temperature rise for each decomposition steps of peroxide compound were obtained, which can be a good index of the hazardousness of reaction. The result was approximate to other experimental and simulation data from references. 

---