A hydrotreating process with a composition which exhibits high induced magnetism in a small applied magnetic field when formed into a magnetically stabilized fluidized bed and which comprises particles containing a nonferromagnetic component, or components, composited with a plurality of elongated ferromagnetic components, randomly oriented and present in each of said particles in relatively low concentration, based on the total volume of the particles; a process for formation of said compositions and a process wherein such composite particles are formed into a magnetically stabilized fluidized bed and contacted with a fluid, preferably gas.