Comer carbides

Therefore, when operating in the filter cake mode, the axial velocity should be maintained at a level such that an adequate shear force exists along the filter media to prevent excessive caking of the catalyst that could cause a blockage in the down-comer circuit. For the separation of ultrafine catalyst particles from FT catalyst/wax slurry, the filter medium can easily become plugged using the dynamic membrane mode filtration. Also, small iron carbide particles (less than 3 nm) near the filter wall are easily taken into the pores of the medium due to their low mass and high surface area. Therefore, pure inertial filtration near the filter media surface is practically ineffective. 

The centers of these icosahedra are located on each of the comers of the rhombohedron as shown in Fig. 7.9 for boron carbide. 

Silicon carbide is a semiconductor material that is why it is a potential catalyst of thermal oxidation and pyrolysis processes. The silicon carbide partieles have sharp comers and it allows to expect the appearance of physical and chemical activity in the processes of adsorption and chemical reactions (due to Ihe presence of unpaired electrons and excess surfece energy). Silicon carbide also can be used as so ealled microbarrier because of its plastic forms on the surface layers of the material. But the usage of silicone carbide in elastomeric materials is poorly understood. 

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