To become more competitive and to diversify their raw material supplier base, polypropylene plants are constructing propylene/propane splitter units, in order to purify refinery grade propylene into polymer grade propylene. The economic analysis presented in this report is based upon the installation of a propylene purification unit inside a polypropylene plant located in US Gulf, China and Germany. For the first two regions, this was demonstraded to be an attractive opportunity. An analysis of the improvement being installed inside a refinery was also developed, making possible the sell of a more valuable product.