Patent GB-1041965-A (GB)
Title: Improvements in and relating to zone refining
IPC: C30B13/00
Filed: 1965-07-09
Abstract: Naphthalene is freed from benzthiophene by passing a plurality of molten zones through a rotating annular body of the material contained in a vessel of cylindrical or frusto-conical shape, a plurality of separate tubes or a cylindrical spiral, the container(s) being only partially filled with the material.  The molten zones may be moved longitudinally and/or transversely with respect to the axis of rotation.  The heater(s) may be located within or outside the material.  The material may be introduced in powdered or molten form. The products may be withdrawn in molten form.  According to Figs. 1 and 2 (not shown), a plurality of annular radiant heaters surround an annular rotary vessel, the heaters being slowly raised one place and then quickly dropped to their original places by means of a cam.  The annular vessel may be replaced by a plurality of tubes arranged in a circle with their axes downwardly converging (Fig. 3, not shown). According to Figs. 4 and 5 (not shown), a cylindrical spiral and a plurality of longitudinal external radiant heaters are rotated at different speeds.  According to Figs. 6 and 7 (not shown), the outer wall of a frusto-conical vessel and a spiral immersion heater are rotated at different speeds.  The spiral heater may be replaced by a plurality of separate heaters (Fig. 8, not shown). According to Fig. 9 (not shown), the vessel has a longitudinal partition and is surrounded by a plurality of longitudinal heaters.  According to Figs. 10 and 11 (not shown), a shallow cylindrical vessel and a pan-cake immersion heater are rotated at different speeds so as to move the molten zones inwards or outwards.  The outer wall may be provided by the material itself. According to Figs. 12-14 (not shown), a rotary vessel contains a stack of pan-cake coils, means being provided for passing hot and cold water in turn through successive batches of coils so as to pass a plurality of zones vertically through the vessel.ALSO:Napthalene is freed from benzthiophene by passing a plurality of molten zones through a rotating annular body of the materal contained in a vessel of cylindrical or frusto-conical shape, a plurality of separate tubes or a cylindrical spiral the container(s) being only partially filled with the material.  The molten zones may be moved longitudinally and/or traversely with respect to the axis of rotation.  The heater(s) may be located within or outside the material.  The material may be introduced in powdered or molten form.  The products may be withdrawn in molten form.  According to Figs. 1 and 2 (not shown), a plurality of annular radiant heaters surround an annular rotary vessel, the heaters being slowly raised one place and then quickly dropped to their original places by means of a cam.  The annular vessel may be replaced by a plurality of tubes arranged in a circle with their axes downwardly converging (Fig. 3, not shown). According to Figs. 4 and 5 (not shown), a cylindrical spiral and a plurality of longitudinal external radiant heaters are rotated at different speeds.  According to Figs. 6 and 7 (not shown), the outer wall of a spiral immersion heater are rotated at different speeds. The spiral heater may be replaced by a plurality of separate heaters (Fig. 8 not shown).  According to Fig. 9 (not shown), the vessel has a longitudinal partition and is surrounded by a plurality of longitudinal heaters.  According to Figs. 10 and 11 (not shown), a shallow cylindrical vessel and a pan-cake immersion heater are rotated at different speeds so as to move the molten zones inwards or outwards.  The outer wall may be provided by the material itself. According to Figs. 12-14 (not shown), a rotary vessel contains a stack of pancake coils, means being provided for passing hot and cold water in turn through successive batches of coils so as to pass a plurality of zones vertically through the vessel.