Patent GB-596162-A (GB)
Title: Improved process for the catalytic synthesis of normally liquid hydrocarbons
IPC: B01J37/02
Filed: 1945-07-23
Abstract: Catalysts for the synthesis of liquid hydrocarbons from CO and H2 are prepared by impregnating a washed silica or silica-alumina hydrogel in jelly form with aqueous solutions of a salt of a hydrogenating metal of Group 8, e.g., Fe, Co or Ni, and of a salt of a metal forming a difficultly reducible oxide, e.g., Mg, Th, Ce, U, Mn or Al, the first named metal being present in greater amount, the impregnated jelly then being drained, dried and heated sufficiently to convert the second named metal to its oxide, and the group 8 metal oxide reduced to the metal. Alternatively, after impregnation, the separated jelly may be treated with sufficient alkali carbonate to precipitate the carbonates of the metals, the mass then being washed, dried to a water content of about 6-10 per cent., and reduced.  The catalysts are resistant to attrition and can be prepared as a powder of suitable size for "fluidized" operation.  The initial silica hydrogel is formed by reacting aqueous sodium silicate with sulphuric, hydrochloric or nitric acid and allowing to set. Silica-alumina gels are made by simple admixture, co-setting or treatment of silica gel with aluminium salt solution followed by ammonia.  Reduction of the Group 8 oxide is effected with hydrogen at about 600-800 DEG F. generally after grinding to the desired particle size.  The carrier may be prepared in spherical particles by mixing the silicate and acid solutions by means of a restricted jet, adding an emulsifying agent, and passing through a second jet wherein the sol. is emulsified with 2-20 times its volume of a substance at least partially immiscible such as butyl alcohols, ether, naphtha, or light gas oil, at temperatures up to 280 DEG F. and pressure up to 50 lb. sq. in.  The sol. is allowed to set while subjecting to constant turbulence.  The spherical hydrogel particles are separated by adding water.  Attrition tests show the low loss of cobalt and thoria in the fines produced from a catalyst prepared from silica hydrogel containing cobalt and thoria and ground to suitable size for fluidized operation, i.e., containing less than 25 per cent. of a size below 20 microns.  The catalysts may contain about 15-40 per cent.  Group 8 metal and 2-10 per cent. metal oxide.  Conditions for the synthesis reaction are those customarily used, temperatures being 325-400 DEG F. for solid bed operation, and 325-550 DEG F. with Co or Ni, 375-700 DEG F. with Fe for fluidized operation.ALSO:Liquid hydrocarbons are synthesized from CO and H2 using a catalyst prepared by impregnating a washed silica or silica-alumina hydrogel in jelly form with aqueous solutions of a salt of a hydrogenating metal of Group 8, e.g. Fe, Co or Ni, and of a salt of a metal forming a difficulty reducible oxide, e.g. Mg, Th, Ce, U, Mn or Al, the first named metal being present in greater amount, the impregnated jelly then being drained, dried, and heated sufficiently to convert the second named metal to its oxide, and the Group 8 metal oxide reduced to the metal. Alternatively after the impregnation, the separated jelly may be treated with sufficient alkali carbonate to precipitate the carbonates of the metals, the mass then being washed, dried to a water content of about 6-10 per cent, and reduced.  The catalysts are resistant to attrition and can be prepared as a powder of suitable size for "fluidized" operation.  The initial silica hydrogel is formed by reacting aqueous sodium silicate with sulphuric, hydrochloric or nitric acid and allowing to set. Silica-alumina gels are made by simple admixture, co-setting or treatment of silica gel with aluminium salt solution, followed by ammonia.  Reduction of the Group 8 oxide is effected after grinding to the desired particle size.  The carrier may be prepared in spherical particles by mixing the silicate and acid solutions by means of a restricted jet, adding an emulsifying agent, and passing through a second jet wherein the sol is emulsified with 2-20 times its volume of a substance at least partially immiscible such as butyl alcohols, ether, naphtha or light gas oil, at temperatures up to 280 DEG  F. and pressures up to 50 lb./sq. in.  The sol is allowed to set while subjecting to constant turbulence.  The spherical hydrogel particles are separated by adding water.  Attrition tests show the low loss of cobalt and thoria in the fines produced from a catalyst prepared from silica hydrogel containing cobalt and thoria and ground to suitable size for fluidized operation, i.e. containing less than 25 per cent of a size below 20 microns.  The catalysts may contain about 15-40 per cent Group 8 metal and 2-10 per cent metal oxide.  Conditions for the synthesis reaction are those customarily used, temperatures being 325-400 DEG  F. for solid bed operation; and 325-550 DEG  F. with CO or Ni, 375-700 DEG  F. with Fe for fluidized operation.