Abstract: The adiabatic calorimeter apparatus disclosed herein is designed for chemical hazard research, particularly the study of self-heating reactions, which can result in a runaway situation. The reaction vessel and associated components in this apparatus closely simulate the structure and operation of a typical chemical plant reactor. The reaction vessel is fitted into a metal shell and the entire unit is suspended in an insulated oven. During the exothermic reaction the adiabatic temperature rise and pressure rise is simultaneously monitored and recorded as a function of time. A first stage control system maintains the temperature of the reaction vessel in equilibrium with the reaction mix and utilizes electrical energy to compensate out the heat capacity effect of the reactor. A second stage control keeps the temperature of the oven and the reaction vessel at the same level, to insure that the reaction is taking place in an adiabatic environment.

Abstract: A novel adiabatic reaction calorimeter useful for measuring the energy change in a chemical reaction is disclosed. In a specific application, the calorimeter is used to measure the heat energy derived in a chemical reaction. The device includes a reaction vessel which is thermally isolated in the geometric center of a sealed spherical chamber. The chamber, which is filled with a gas atmosphere, is defined within a box structure fabricated of a ceramic foam or plastic foam. An auxiliary vessel is positioned in the chamber adjacent to the reaction vessel and is connected to the reaction vessel by a transfer conduit.In a typical operation, prior to initiating the reaction, one reactant is contained in the reaction vessel and another reactant in the auxiliary vessel. The vessels and the gas atmosphere are heated to a predetermined temperature by electrical power units, with regulation by a temperature control unit.