Catalytic decomposition of hydrogen peroxide in the presence of alkylpyridines:: Runaway scenarios studies

A number of runaway scenarios of the excess of hydrogen peroxide used during the N-oxidation of alkylpyridines, under closed and open conditions, were examined. It was found that, in most cases, if the volume of the liquid hydrogen peroxide solution occupies more than 10% of the total volume of a closed system (e.g. reactor and vent line between reactor and blockage), the production of gases raises the pressure so quickly that evaporation is completely suppressed. Higher than 70% filling levels result in complete expansion of the liquid. The MTSR(t) of the system falls rapidly if the normal process temperature is high, but if a runaway occurs exactly at the end of dosing, MTST will be very high and secondary decompositions will rapidly develop. The results of this study are currently being used to critically assess the current approaches and further the study of inherently safer designs. (c) 2005 Elsevier Ltd. All rights reserved.