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Abstract: Sorption enhanced methane reforming (SER), employing a CaO-based solid as a high temperature CO2 sorbent, is generally considered to be a promising route for H2 production. In this paper we present a dynamic pseudo-homogeneous model to describe the operation of a packed bed reactor in which the SER reaction is carried out under adiabatic conditions. This reactor can be implemented according to several process schemes, including a novel Ca/Cu looping process for hydrogen generation with inherent CO2 capture. The proposed SER model is based on the well-established principles of gas–solid contact and heat transfer in fixed-bed reactors and on the kinetic expressions published in the literature that describe the main reactions involved in the process. The resulting model describes the transient performance of the SER reaction and confirms the theoretical viability of this critical reaction stage in a large scale H2 production facility. It is demonstrated that the SER process can yield a CH4 conversion and H2 purity of up to 85% and 95%, respectively, under operating conditions of 923K, 3.5MPa, a steam/carbon ratio of 5 and a space velocity of 3.5kg/m2 s. [Copyright &y& Elsevier]

Abstract: This paper considers a new approach of improving the efficiency of adsorption–catalytic removal of volatile organic compounds (VOCs) from waste gases based on the use of a combined structured fixed bed consisting of a coarse-grained adsorbent–catalyst and a microfiber catalyst. Numerical mathematical modeling showed that during high-temperature oxidative regeneration of the adsorbent–catalyst, the microfiber catalyst (∼0.01mm in diameter) is heated much faster than large pellets (∼2–20mm in diameter) of the adsorbent–catalyst due to the significantly higher external specific surface area (∼500–5000 times greater). This allows one to efficiently oxidize unoxidized VOCs desorbed from the surface of the adsorbent–catalyst, thus minimizing the desorption losses and significantly increasing the degree of gas purification (up to 99%). [Copyright &y& Elsevier]