Direct Conversion of Shale Gas Alkanes to Commodity Chemicals

Direct conversion of shale gas to useful chemicals or fuels has faced the central challenge that reaction rates and product yields high enough to be economic are accompanied by overreaction to full combustion products in either conventional or unconventional approaches. We are developing an integrated process combining alkane activation via oxidative coupling to form ethylene or higher alkene oligomers, which will be followed by direct-fed integrated ethylene to fuels process. A viable direct shale gas to fuels and/or chemicals process offers substantial energy savings with significantly reduced process complexity and capital intensity, as compared to industrially practiced large-scale indirect routes which include methane-steam reforming, followed by watergas shift, and then methanol synthesis or Fischer-Tropsch upgrading. While extensively investigated, this direct pathway is problematic due to reaction engineering constraints. Common features of both the oligomerization and ethylene polymerization reactions include potential to overreactions, especially to combustion products or waxy polymers, reaction rate limitations related to mass transfer, or need to moderate reaction rates due to excessive adiabatic heat of reactions. PCIs reactor technology has been developed to overcome these limitations while maintaining effectiveness of the catalysts. In Phase I we completed proof-of-concept testing that demonstrated the viability of our approach. Specifically, for reactions involving an overly reactive component, in this case oxygen, we were effective in limiting overreaction to carbon dioxide and carbon monoxide, enhancing the yields of ethylene, while maintaining overall methane conversion levels, creating a pathway towards developing a economically viable process that will perform equally well in both small and larger scale projects. In Phase II, we will further develop our reactor technology for long term robustness, conduct small-scale pilot unit testing, and develop modeling tools directed at developing a process design package. The overall goal of the Phase II program will be to develop the design and operating specifications to enable a pilot-scale demonstration of our CMT reactor technology for the ethylene synthesis component of a shale-gas to gasoline or chemicals project. Success would simultaneously cut the costs of transportation fuels while also improving American energy independence and reduce greenhouse gas emissions.