Three-phase fixed-bed reactors are very often encountered in industrial applica- tions for carrying out different chemical reactions between gaseous and liquid reactants on porous catalysts, in processes such as, hydrogenation, hydrotreating, purification, the Fischer–Tropsch synthesis, and in many others. These processes form the basis for production of a large variety of intermediate and ultimate products in refinery, bulk and fine chemistry, in manufacture of monomers, sol- vents, pharmaceuticals, fragrances, fuels, food additives, etc
