We have developed and evaluated a carbon filter to remove dimethyl sulfoxide (DMSO) vapor from the exhaust of the W79 HE (high explosive) Dissolution Workstation. A series of laboratory tests were conducted on eight different carbon samples to establish the vapor breakthrough curves and to select the best sample. Empirical equations were developed to predict the breakthrough curve for various air flows and bed thickness, These equations were used to design the filter cartridge. The filter

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... ts of a cylindrical cartridge 12 inches high and 6 and 10 inches inside and outside diameter and has a pressure drop of 0.8 inches of water at 50 cfm. Experiments and computations verified the efficiency of the filter cartridge is greater than 99% at 35 cfm, and the carbon filter can process 60 HE assemblies while maintaining greater than 90% efficiency before the carbon must be replaced. This study describes the development of a carbon filter that is a component of the exhaust system for the W79 HE Dissolution Workstation as shown in Figure 1 . The Workstation is designed to support the DOE nuclear weapons dismantlement program in which hot DMSO sprays are used to dissolve the HE from HE assemblies. The description of the W79 Workstation and the complete air cleaning system is given in a previous report (I). We developed the carbon filter because commercially available units were either designed for much larger ventilation systems or had excessive pressure drops. The typical ventilation filter has a 2' x 2' cross sectional area and is designed for flow rates of 1,000 cfm or greater. Smaller annular cartridge filters were developed for military vehicle applications but have pressure drops that greatly exceed the requirement of less than one inch of water at 50 cfm. In addition to the lack of suitable carbon filter units, there also is no information on the performance of carbon filters for removing DMSO vapors. Thus, we had to establish the basic adsorption characteristics in addition to the design parameters to develop the DMSO carbon filter. The initial step was to demonstrate that activated carbon was effective in removing DMSO vapors. ----1------1----^--1____I____D____I_____----------------------------