Fluid catalytic partial oxidations

Fluid-solid MSR have been extensively used particularly for gas-solid reactions such as catalytic partial oxidations, selective hydrogenations, dehydrogenations, dehydrations, and reforming processes [57, 58]. Similarly to the other reactions carried out in MSR, the main objective was to achieve better temperature control in order to prevent selectivity loss, catalyst deactivation, hot spot formation and, thus, allowing safe processing with high throughput. 

The volatile products from the soaking drum enter the fractionator where the distillates are fractionated into desired product oil streams, including a heavy gas oil fraction. The cracked gas product is compressed and used as refinery fuel gas after sweetening. The cracked oil product after hydrotreating is used as fluid catalytic cracking or hydrocracker feedstock. The residuum is suitable for use as boiler fuel, road asphalt, binder for the coking industry, and as a feedstock for partial oxidation. 

Foams were proved to be highly suitable as catalytic carrier when low pressure drop is mandatory. In comparison to monoliths, they allow radial mixing of the fluid combined with enhanced heat transfer properties because of the solid continuous phase of the foam structure. Catalytic foams are successfully used for partial oxidation of hydrocarbons, catalytic combustion, and removal of soot from diesel engines [14]. The integration of foam catalysts in combination with microstructured devices was reported by Yu et al. [15]. The authors used metal foams as catalyst support for a microstructured methanol reformer and studied the influence of the foam material on the catalytic selectivity and activity. Moritz et al. [16] constructed a ceramic MSR with an inserted SiC-foam. The electric conductive material can be used as internal heating elements and allows a very rapid heating up to temperatures of 800-1000°C. In addition, heat conductivity of metal or SiC foams avoids axial and radial temperature profiles facilitating isothermal reactor operation. 

Yuan, R, Cheng, Z., Jiang, W., et al. (2005). Catalytic desulfurization of residual oil through partial oxidation in supercritical water, J. Supercrit. Fluid, 35, pp. 70-75. 

Partial wet oxidation or controlled wet oxidation is, in a sense, similar to that of catalytic oxidation. Catalytic oxidation provides a conventional catalyst in order to boost and control the oxidative reaction, whereas wet oxidation provides a favored atmosphere for the reaction to occur. More accurately, catalytic oxidation provides a surface upon which intimate contact between the reactants takes place compared to the thermodynamic (or fluid dynamic) contact provided by wet oxidation. In wet oxidation, it can be said that the supercritical water phase acts as the "catalyst for the reaction. 

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