This paper was presented at the 4th Micro and Nano Flows Conference (MNF2014), which was held at University College, London, UK. The conference was organised by Brunel University and supported by the Italian Union of Thermofluiddynamics, IPEM, the Process Intensification Network, the Institution of Mechanical Engineers, the Heat Transfer Society, HEXAG - the Heat Exchange Action Group, and the Energy Institute, ASME Press, LCN London Centre for Nanotechnology, UCL University College London, UCL Engineering, the International NanoScience Community, www.nanopaprika.eu.The Fischer-Tropsch (FT) reaction is a highly exothermic reaction. The high exothermicity
combined with a high sensitivity of product selectivity to temperature, constitute the main challenges in the
design of FT reactors. The use of micro-encapsulated- Phase Change Material (PCM) in conjunction with the
supervisory temperature control mechanism has been suggested as an effective way of mitigating these
challenges. A 2-dimensional, pseudo-homogeneous, steady-state model, with the dissipation of the enthalpy
of reaction into an isothermal PCM sink, in a fixed bed reactor is presented. Effective temperature control
with the PCM shows a shift in thermodynamic equilibrium favouring the selectivity of C5 to the
disadvantage of CH4 selectivity - a much desired outcome in the hydrocarbon Gas-to-Liquid industry
