Solvent selection for commercial supercritical Fischer–Tropsch synthesis process

This paper describes a preliminary in-depth analysis of the techno-economic criteria for solvent selection for the supercritical fluids Fischer–Tropsch synthesis (FTS). Both conventional media (i.e. gas phase FTS and liquid phase FTS) as well as non-conventional media (near-critical and supercritical phase FTS) were examined, with an emphasis on non-conventional media FTS for the design and commercialization purposes of a novel FTS reactor technology. A wide array of hydrocarbon solvents were reviewed, ranging from propane to decane, with numerous blends of two or more of the mentioned paraffins; several fuel cuts were studied as well, such as light and heavy naphtha and diesel. Also, the interaction of the solvents with in situ reaction mixture and products were studied to further insure single phase operation and process feasibility. A concurrent examination of the techno-economic analysis for solvent selection was carried out; this is of utmost importance since the economic incentives as well as the technical conquest (i.e. overcoming design limitations) are the basis for the novel approach to the reactors design and commercialization of this novel technology.

Research Highlights
► Search appropriate solvents for commercial supercritical Fischer-Tropsch process.
► Selection criteria: phase behavior, availability, and technoeconomic considerations.
► Data was cross referenced with AspenTech® AspenPlus simulation software.
► Equations-of-State & mixing rules were verified & phase behavior studies executed.
► Either unreformed or light Naphtha was found to be the best compatible solvent.