Jonas Model Applicability for Predicting Organic Vapor/Gas Cartridge Performance: Theory, Method, and Preliminary Findings

摘要

An evaluation was undertaken of the Jonas kinetic model for routinely evaluating the performance of organic vapor (OV) cartridges. The model could be useful in predicting OV breakthrough characteristics for untested vapors by predicting cartridge life against a wide range of compounds. Commercially available OV respirator cartridges were tested in a stacked configuration to resemble packed columns of varying bed length and sorbent weight to evaluate the applicability of the approach. The Jonas model has shown that the kinetic adsorption capacity and gas adsorption rate of a packed charcoal sorbent bed is described by the linear relationship between gas breakthrough time and sorbent weight as predicted by a modified Wheeler equation. The modified Wheeler equation was a simple mathematical formulation relating breakthrough time with two adjustable parameters, the capacity parameter and the kinetic parameter. The kinetic parameter was uncertain and depended on the method of data analysis employed, a limitation of the method until the influences on this parameter can be better identified. Further study is needed at other than baseline conditions before conclusions can be drawn as to the adaptability of the method for wider usage.