Patent GB-865636-A (GB)
Title: Preparing lubricating oils using radiation
IPC: C07C9/14
Filed: 1958-01-01
Abstract: <PICT:0865636/IV (b)/1> Lubricating oil fractions in the boiling range 750-950 DEG F., and showing a maximum viscosity index at an intermediate viscosity, are obtained by irradiating a paraffinic feed boiling in the range 100-700 DEG F. with high energy radiation, at a temperature between the pour point of the feed and 700 DEG F., until at least 5 X 10-3 but not more than 1 KWH per pound of feed of radiation has been absorbed, to obtain a conversion of at least 1 weight per cent. of feed per pass.  The product is fractionated to recover an intermediate lubricating oil fraction of boiling range 750-950F., having a viscosity in the range 35-70 SSU at 210 DEG F. and a viscosity index above 120.  Lower boiling product may be recycled to the radiation zone.  In the apparatus shown the feed is irradiated in zone 2 and the product fractionated in zone 4. Part of the product may be recycled before fractionation by line 10.  High boiling products from zone 4 may be cracked thermally, catalytically or by irradiation in a separate part of zone 2 or used as lubricants of the cylinder or bright stock type having a viscosity at 210 DEG F. of 150 SSU.  Desired product of intermediate range is removed at line 5, or after a further separation, e.g. by dewaxing or removal of aromatics, removed in two streams of higher and lower viscosity index by lines 5 and 8.  Part of the line 5 product may be returned to a separate part of zone 2 by line 11 to obtain a further increase in viscosity.  Light products are removed at 6.  In Examples: (1) 600 c.c. of nhexadecane were irradiated in a nuclear reactor at 260 DEG F., under a flux of 3 X 1012 neutrons per sq. cm. per sec and 1.6 megaroentgens per hour of gamma radiation, for two days until 300 X 10-3 KWH per pound had been absorbed.  The product, which showed a viscosity index maximum at a viscosity of 40 SSU, was fractional to give a product boiling in the range 700-900 DEG F. having a viscosity of 38.5 SSU at 210% a viscosity index of 145 and a +40 DEG F. pour point which reduced to 0 DEG F. after dewaxing.  (2) cetane was irradiated in a nuclear reactor at a dose rate of 4 X 10-3 KWH/lb./hour for about 5 hours at 200-400 DEG F.  The product was fractionated and the viscosity and viscosity index of the fractions measured.  Maximum viscosity index occurred at a viscosity of 40 SSU at 210 DEG F.  Reference has been directed by the Comptroller to Specifications 802,552, 814,562, 823,099 and 840,825.ALSO:<PICT:0865636/III/1> Lubricating oil fractions in the boiling range 750-950 DEG F., and showing a maximum viscosity index at an intermediate viscosity, are obtained by irradiating a paraffinic feed boiling in the range 100-700 DEG F. with high energy radiation, at a temperature between the pour point of the feed and 700 DEG F., until at least 5 X 10-3 but not more than 1 KWH per pound of feed of radiation has been absorbed, to obtain a conversion of at least 1% weight of feed per pass.  The product is fractionated to recover an intermediate lubricating oil fraction of boiling range 750-950 DEG F., having a viscosity in the range 35-70 SSU at 210 DEG F. and a viscosity index above 120.  Lower boiling product may be recycled to the radiation zone.  In the apparatus shown the feed is irradiated in zone 2 and the product fractionated in zone 4.  Part of the product may be recycled before fractionation by line 10. High boiling products from zone 4 may be cracked thermally, catalytically or by irradiation in a separate part of zone 2 or used as lubricants of the cylinder or bright stock type having a viscosity at 210 DEG F. of 150 SSU.  Desired product of intermediate range is removed at line 5, or after a further separation, e.g. by dewaxing or removal of aromatics, removed in two streams of higher and lower viscosity index by lines 5 and 8.  Part of the line 5 product may be returned to a separate part of zone 2 by line 11 to obtain a further increase in viscosity.  Light products are removed at 6.  In Examples: (1) 600 c.c. of n-hexadecane were irradiated in a nuclear reactor at 260 DEG F., under a flux of 3 X 1012 neutrons per sq. cm. per sec. and 1.6 megaroentgens per hour of gamma radiation, for two days until 300 X 10-3 KWH per pound had been absorbed.  The product, which showed a viscosity index maximum at a viscosity of 40 SSU, was fractionated to give a product boiling in the range 700-900 DEG F. having a viscosity of 38.5 SSU at 210 DEG F., a viscosity index of 145 and a +40 DEG F. pour point which reduced to 0 DEG F. after dewaxing.  (2) cetane was irradiated in a nuclear reactor at a dose rate of 4 X 10-3 KWH/lb./hour for about 5 hours at 200-400 DEG F.  The product was fractionated and the viscosity and viscosity index of the fractions measured.  Maximum viscosity index occurred at a viscosity of 40 SSU at 210 DEG F.  Reference has been directed by the Comptroller to Specifications 802,552, 814,562, 823,099 and 840,825.