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While Fischer-Tropsch synthesis (FTS) using coal and natural gas in conventional reactors is an almost well-established technology, the production of liquid hydrocarbons from syngas obtained from biomass is in its preliminary stages of commercialization in countries like Germany. With concerns about global warming and ways of disposing of CO2 being searched for, CO2 hydrogenation using FTS to liquid hydrocarbons can act as a CO2 sink. A brief review of FTS using CO2-rich syngas is given in this paper, looking at FTS as a technology that can help reduce global warming and as a process integration alternative. The reverse water gas shift (r-WGS) reaction is vital for CO2 hydrogenation. We have studied the effect of this using an FT kinetic model and have proposed a new flow sheet alternative for FTS using CO2-rich syngas. Simulations suggested that this new process gives better conversion of CO2. The product selectivity and yields from an FT plant are vital to make the process viable economically.

In this paper, we study the potential of entrainer in reactive distillation involving high boiling reactants to decrease the reactive stage temperature and for separation of one of the products to enhance the conversion. Esterification of ethylene glycol with acetic acid in the presence of Amberlyst 36 with 1,2-dichloro ethane (EDC), as an entrainer, is chosen as the model reaction. The effect of different parameters on selectivity of diacetate of ethylene glycol (DAEG) in entrainer based reactive distillation (EBRD) has been studied both through experiments and simulations. The results show that, by using entrainer, it is possible to obtain close to 100% selectivity toward diester even with a stoichiometric mole ratio, which is otherwise not possible in a conventional reactor.

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Fischer-Tropsch synthesis (FTS) is an area that is receiving revived interest worldwide as a technology alternative to produce transportation fuels as well as chemicals from syngas. SASOL and Shell are two of the major players who operate FT reactors on a commercial scale. To have a balance between gasoline and diesel production, one needs to have both the low temperature (LTFT) and high-temperature (HTFT) processes operating in parallel. Heat-removal from the exothermic FT reactions was the main driver in the development of conventional FT reactors (fixed-bed, fluidized bed, or slurry type). However, the focus has recently shifted toward the product distribution as well. Reactive distillation (RD) is a proven reactive separation method that can enhance yields as well as improve product selectivity in multiple reactant/product systems. This paper aims to check if FTS is feasible in RD from a theoretical viewpoint. In-built thermodynamic procedures and power-law kinetics of Aspen Plus, along with a simplified kinetic model that predicts product distribution, were used in performing the simulations. Simulation results of the conventional reactors are compared with RD, and it is seen that the performance of RD is at par or better than the conventional reactors in terms of conversion, yield, and product distribution. Within the RD mode for FTS, results of some of the alternate column configurations are presented. The results indicate that FTS can be a potential candidate to be implemented using RD.

The search for alternative sources of transportation fuels and energy security have revived an interest in the Fischer−Tropsch Synthesis (FTS) technology. Over the years, the main driver in FT reactor development has moved from the exothermic heat removal to the product distribution and selectivity. Reactive distillation (RD), a proven reactive separation method that can enhance yields and improve product selectivity in multiple reactant/product systems, was shown to be feasible for FTS in our earlier paper using a simplified kinetics [Srinivas, et al. Feasibility of Reactive distillation for Fischer−Tropsch Synthesis. Ind. Eng. Chem. Res. 2008, 48, 889−899]. This paper looks at the feasibility using a detailed kinetics incorporating olefin readsorption. In-built thermodynamic procedures of Aspen Plus, along with a detailed kinetic model that predicts product distribution, were used in performing the simulations. Some insight is given on the thermodynamics and kinetics used in performing the simulations. Conversion, yield, olefin-to-paraffin ratio, and product distribution are the parameters used for comparison among the different reactor types. Simulation results of the conventional reactors are compared with RD and it is seen that the performance of RD is at par or better than the conventional reactors.

A series of Ti02-Zr02 mixed oxide supported vanadia catalysts with various V2O5 loadings ranging from 1 to 16 wt W were prepared by a wet impregnation method and were characterized by means of solid-state slV and 'H NMR spectroscopic techniques. The solid-state 51V NMR spectra of V205/TiO2-ZrOZ catalysts reveal the existence of two types of dispersed surface vanadium oxide complexes in a tetrahedral oxygen environment at lower vanadium loadings and a tbird thrediensional crystalline V2O5 in distorted octahedral environment at higher vanadium contents. The proton NMR results provide evidence for the existence of metal oxide support interaction through the support surface hydroxyl groups.