A Novel Chemical Heater System for Mustard Detection in the XM256 Chemical Agent Detector Kit

摘要

A Chemical heater formulation was developed for use in the XM256 chemical agent detector kit for the detection of mustard (H) by the 4-(p-nitrobenzyl)pyridine (DB3) test. Previous experience had indicated that a temperature of 100C maintained for 6 seconds is required to bring the first step of the H-DB3 reaction to completion in order to obtain the optimum color development under the conditions utilized in the kit. To attain this temperature, an external chemical heater is placed adjacent to the test strip. As presently constituted, the heater employs a 30% cupric chloride solution that is added to aluminum powder to produce a reaction with the evolution of heat. This investigation is centered solely around the exothermic, displacement reaction of copper from cupric chloride by aluminum. As compared to a peak temperature of 90C by employing a 30% aqueous cupric chloride solution, a novel system was devised whereby a peak temperature of 156C was attained and a temperature of 100C or higher was maintained for 11/2 minutes. This unique formulation composed of cupric chloride, a wetting agent, water, and ethylene glycol remained a dark green homogeneous solution after standing in a freezer for over 30 days. (Author)