The objective of this work was to establish fixed bed sorption enhanced reactors (SER) and simulated moving bed reactors (SMBR) for the production of high purity biodiesel (fatty acid methyl ester, FAME) using esterification reactions between fatty acids (FA) in used oils and methanol. This study has demonstrated that these processes have tremendous potential in terms of overcoming the low conversion and separation difficulties that are faced in conventional biodiesel production processes. Additionally, the SMBR process operating conditions can be optimized to produce FAME at a desired purity in a continuous mode. The novelty of this work lays in the development of generic and comprehensive dynamic simulation and systematic parametric analysis frameworks. These were used to deduce the following operating conditions for achieving more than 90% conversion of FA and 80% purity of FAME, from an SMBR process: switching time of 900 s, length of 0.25 m, and feed, raffinate, and eluent flow rate ratios of 0.41, 0.49, and 0.75, for a given velocity of 2.4 × 10−4 m/s in the reaction zone.

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The heterogeneously catalysed transesterification reaction for the production of biodiesel from Triglycerides was investigated for reaction mechanism and kinetic constants. Three elementary reaction mechanisms Eley-Rideal (ER), Langmuir-Hinshelwood-Hougen-Watson (LHHW), andHattori with assumptions such as quasi steady state conditions for the surface species and methanol adsorption, and surface reactions as the rate determining steps were applied to predict the catalyst surface coverage and the bulk concentration using a multi-scale simulation framework. The rate expression based on methanol adsorption as the rate limiting in LHHW elementary mechanism has been found to be statistically the most reliable representation of the experimental data using hydrotalcite catalyst with different formulations.

in Wiley InterScience (www.interscience.wiley.com).A multiscale simulation and characterization framework has been developed for sorption enhanced reaction processes with heterogeneous multifunctional catalysts with sorption properties. Particles with in situ catalytic and sorption functionalities have obvious advantages in achieving high-purity and productivity. These processes are strongly limited by diffusion inside particle. In order to tackle this problem a more detailed characterization at particle level is essential, which is the main objective here. A unified framework has been developed that integrates continuum model at bulk scale with the diffusion-reaction-sorption model at particle porous scale in a fixed-bed reactor. At bulk scale the objectives of purity and productivity are sensitive to various design and operating variables, such as wall temperature, bed voidage and feed compositions, etc. Two important particle level characteristics are also identified: distribution of catalyst and sorbent inside particles, and the ratio of pore radius to tortuosity. It has been demonstrated that considering detailed diffusivity model at porous level offers better insights into catalyst design and process intensification. Natural gas reforming reaction with sorption producing pure hydrogen for fuel cell and combustion applications has been used as a case study to establish the effectiveness of the methodology.

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