Composition for use in a magnetically fluidized bed

As a composition of matter, a particulate material which can be oriented within, and formed into a magnetically stabilized fluidized bed to provide high magnetization at a low applied field which comprises particles of geometrically elongate shape which have a major axis at least 1.2 times the length of the minor axis, the particles being of average diameter (minor axis) ranging from about 10 .mu.m to about 4000 .mu.m and contain a nonferromagnetic component, composited with a plurality of elongate ferromagnetic components, the ferromagnetic components being multidomain, having dimensions of at least 1 .mu.m in all directions, elongated in two directions, and having a length:diameter (L/D) ratio of at least 2 and not more than 313, the nonferromagnetic component being comprised of alumina within which said ferromagnetic components are dispersed as inclusions within the interior of the composite particles, and aligned with the major axis of said particles the ferromagnetic components being oriented with their long dimensions essentially parallel, the ferromagnetic components constituting at least 0.5 percent, but not more than .pi./2(L/D+1), of the total volume of each particle, where L/D is the average ratio of the longest dimension of a ferromagnetic inclsuion relative to the shortest dimension, and, in said magnetically stabilized fluidized bed, the particles can rotate, or turn to line up said ferromagnetic components essentially parallel to the direction of the field, and wherein a catalytically effective amount of a catalytically active metal is dispersed on the surface of the composite, and the composite particles are catalytically active.