(741c) Adsorption of Biomass-Derived Value-Added Chemicals in a Micro-Packed-Bed Reactor. a CFD Study

Utilizing cellulosic biomass conversion technologies towards the production of fuels and chemicals is of topical character. Among those technologies, a series of reactions to convert hexoses to value-added intermediates such as 5-Hydroxylmethylfurfural (5-HMF), is of great importance.¹ However, intensifying these processes requires the integration of advanced processes including integrative reaction-separation schemes such as the one proposed in this study. This work discusses a continuous flow reactor where adsorption and reaction occur in a single packed bed reactor unit. Experimental and computational studies^2,3,4 are used to elucidate the critical parameters that affect the design of micro-packed bed reactor for enhanced adsorption of 5-HMF.

A three-dimensional computational fluid dynamics (CFD) model of a packed bed microreactor is developed in order to study the adsorption of 5-Hydroxylmethylfurfural (5-HMF), a valuable intermediate in the production of para-xylene (PX) from biomass sources. The ultimate goal of this work is to provide information about the design parameters that need to be controlled in order to implement a temperature swing reactive adsorption microreactor using a carbon adsorbent (BP 2000). In this work, we will discuss in detail the effects of the microreactor dimensions, the operating conditions, and the porous media on the flow patterns as well as adsorption. Towards this, we perform CFD simulations at different void fractions, porosity as well as particle diameter. Particle scale geometries and uniform porous zone scenarios are studied thoroughly for comparison. The optimal design is decided based on output parameters including pressure drop, residence time, and outflow velocity. In addition, a set of simulations will be discussed where reactive adsorption and desorption of biomass-derived chemicals of interest take place on the packed bed particles. A combination of adsorption experiments at different flow conditions is used to validate our simulations.

1. Van Putten, R.J., Van Der Waal, J.C., De Jong, E.D., Rasrendra, C.B., Heeres, H.J. and de Vries, J.G., 2013. Hydroxymethylfurfural, a versatile platform chemical made from renewable resources. Chemical reviews, 113(3), pp.1499-1597.
2. Partopour, B. and Dixon, A.G., 2016. Computationally efficient incorporation of microkinetics into resolved-particle CFD simulations of fixed-bed reactors. Computers & Chemical Engineering, 88, pp.126-134.
3. Rebughini, S., Cuoci, A. and Maestri, M., 2016. Handling contact points in reactive CFD simulations of heterogeneous catalytic fixed bed reactors. Chemical Engineering Science, 141, pp.240-249.
4. White, J., 2013. CFD simulation of silica gel and water adsorbent beds used in adsorption cooling system(Doctoral dissertation, University of Birmingham).