Patent GB-670423-A (GB)
Title: Improvements in and relating to the separation of catalysts from liquid products
IPC: C07C45/50
Filed: 1949-01-24
Abstract: In the reaction of organic compounds with CO and H2 in the liquid phase and under super-atmospheric pressure, wherein the products contain compounds of the ferromagnetic metals with CO\sBH2, the partial pressure of CO over the product is reduced to precipitate the metal which is separated by subjecting to a magnetic field.  Olefins, especially aliphatic C2-C12 mono-olefins, may be carbonylated to aldehydes using as catalyst a metal carbonyl, added as such or formed in situ.  With lower olefins, an organic compound is added to provide the liquid phase.  The magnetic field may be applied by permanent or electromagnets, and a series of fields of increasing strength in the direction of liquid flow may be used.  Magnetic filters as described in Specification 527,771, [Group II], wherein a field is set up in gaps lying in the fluid but out of the stream of flow, the extracted particles being retained in the gaps, may be used.  Reduction of the partial pressure of CO may be effected by reducing the total pressure or by passing inert gas or hydrogen through the liquid product. Pressures of 150-300 atmos. are suitable, and temperatures are chosen so that substantially zero pressure of CO is rapidly attained, e.g. 150-170 DEG  C., at 250 atmos.  A long tubular vessel containing a string or strings of cylindrical magnets threaded on a non-magnetic rod and separated by non-metallic cylinders, each magnet provided with mild steel polepieces having rounded edges may be used.  The metal in the separator may be treated with CO and an organic liquid, and the solution of carbonyl returned to the reactor.  The purified products such as aldehydes may be hydrogenated at the same pressure to alcohols.  In an example, di-isobutene is carboxylated at 155 DEG C. and 250 atmos., the liquid product treated with hydrogen, and the cobalt produced separated by a series of cylindrical magnets. Specification 655,339 also is referred to.ALSO:In the reaction of organic compounds with CO and H2 in the liquid phase and under superatmospheric pressure with a metal carbonyl, added as such or formed in situ, as catalyst, and wherein the products contain compounds of the ferro-magnetic metals with CO \sB H2, the partial pressure of CO over the product is reduced to precipitate the metal which is separated by subjecting to a magnetic field, and may be treated with CO and an organic liquid to form a solution of metal carbonyl which is returned to the reactor.  The magnetic field may be applied by permanent or electromagnets, and a series of fields of increasing strength in the direction of liquid flow may be used. Magnetic filters as described in Specification 527,771, [Group II], wherein a field is set up in gaps lying in the fluid but out of the stream of flow, the extracted particles being retained in the gaps, may be used.  Reduction of the partial pressure of CO may be effected by reducing the total pressure or by passing inert gas or hydrogen through the liquid product.ALSO:In the reaction of organic compounds with CO and H2 wherein the products contain compounds of the ferromagnetic metals, the partial pressure of CO over the product is reduced to precipitate the metal which is separated by subjecting to a magnetic field.  The magnetic field may be applied by permanent or electromagnets, and a series of fields of increasing strength in the direction of liquid flow may be used.  Magnetic filters as described in Specification 527,771, wherein a field is set up in gaps lying in the fluid but out of the stream of flow, and extracted particles being retained in the gaps, are suitable.  A long tubular vessel containing a string or strings of cylindrical magnets threaded on a nonmagnetic rod and separated by non-metallic cylinders, each magnet provided with mild steel pole pieces having rounded edges may be used.