Adsorptive separations have gained considerable importance in process industry. A generic simulator has been developed in this work for Pressure Swing Adsorption (PSA) processes. Several simple and complex, conventional and unconventional PSA cycles have been studied using this simulator. Distinction has been made between PSA processes where a raffinate stream richer in the weakly adsorbed component as compared to the feed is the desired product as against processes where extract stream richer in the strongly adsorbed component is the desired product. These are termed as raffinate PSA and extract PSA respectively. Extract PSA is an unconventional process variation. The studies include several simple and complex PSA cycles for raffinate and extract PSA of industrial importance. The studies are aided by a generic simulator for all PSA process variations developed for the purpose. The simulator is equally applicable to Vacuum Swing Adsorption (VSA), Pressure Vacuum Swing Adsorption (PVSA), rapid cycle PSA processes, etc.