Patent GB-704145-A (GB)
Title: Method for the fractionation of mixtures containing dicyclo-pentadiene and other materials boiling below dicyclopentadiene
IPC: B01D3/14
Filed: 1950-07-20
Abstract: In the treatment of the forerunnings of crude benzole and other liquid mixtures which contain dicyclopentadiene, the light components, such as carbon disulphide, are removed either by passing an inert gas through the mixture or by distilling it under reduced pressure, the temperature of the mixture in either method being maintained below 105 DEG C. and preferably below 25 DEG C.; and the liquid residue is submitted to distillation, preferably steam p distillation, to separate dicyclopentadiene.  The process obviates the decomposition of dicyclopentadiene into monocyclopentadiene. Crude benzole from tank 1 is treated with lime or milk of lime in mixer 2 in order to remove <PICT:0704145/IV(b)/1> hydrocyanic acid and hydrogen sulphide.  The oil is then heated at 80 DEG C. for four hours in closed container 3, into order to convert mono-into dicyclopentadiene.  The oil is then conveyed to thermally-insulated container 5, wherein it is aspirated for 5-hours with cleaned coke oven gas at 15 DEG C. introduced at the rate of 5 cubic metres per minute through duct 6.  The temperature of the liquid in container 5 decreases to less than 0 DEG C. owing to volatilization of the light components.  The residue from container 5, which contains benzene and dicyclopentadiene, is passed through pipe 41 to still 42 where it is separated into its components by steam distillation, the steam being introduced through pipe 43, and the distillate being condensed in condenser 45.  The vapour laden gas leaving container 5 is passed to adsorption chambers charged with activated coal or silica gel.ALSO:In the treatment of the forerunnings of crude benzole and other mixtures which contain dicyclopentadiene, the light components, such as carbon disulphide, are removed either by passing an inert gas through the mixture or by distilling it under reduced pressure, the temperature of the mixture in either method being maintained below 105 DEG C., and preferably below 25 DEG C.; and the liquid residue is submitted to distillation, preferably steam-distillation, to separate dicyclopentadiene.  The method obviates the decomposition of dicyclopentadiene into monocyclopentadiene.  Crude benzole from tank 1 is treated with lime or milk-of-lime in mixer 2 in order to remove hydrocyanic acid and hydrogen sulphide.  The oil is then heated at 80 DEG C. for four hours in closed-container 3. in order to convert mono-into dicyclo-pentadiene.  The oil is then conveyed to thermally-insulated container 5, wherein it is <PICT:0704145/III/1> aspirated for 5 hours with cleaned coke oven gas at 15 DEG C., introduced at 5 cubic metres per minute through duct 6.  The temperature of the liquid in container 5 decreases to less than 0 DEG C. owing to volatilization of the light components.  The vapour-laden gas leaving container 5 is passed to a group of adsorption containers (10, - - - 13) which are brick lined and are charged with activated coal arranged on hurdles.  The bottom of each container is connected to the top of the next through a cooler 19, which is used to cool the gas to 15 DEG C.  The gas leaving adsorber 13 is passed through pipe 25 to scrubber 26 where it is treated with sulphuric acid; and the scrubbed gas, after being cooled in cooler 27, is partly returned to container 5 via blower 28 and ducts 29, 6.  After the adsorber group (10, - - - 13) has been on-steam for 2 hours, valve 8 is shut and valve 9 is opened, so that the gas from container 5 passes to the lower adsorber group (14, - - - 17).  The adsorption containers in the upper group are then individually regenerated, one after another, by introducing steam for 1 hour through pipe 32; and the expelled vapours, mixed with steam, are passed through line 34 to condenser 35.  In this way, four different fractions are obtained.  The adsorbers are dried by passing coke oven gas, heated to 110 DEG C. by heater 37, into them from pipe 39; and this is followed by cold coke oven gas so that the adsorbers are cool before being put on-steam again.  The residue from container 5, which contains benzene and dicyclopentadiene, is passed through pipe 41 to still 42 where it is separated into its components by steam-distillation, the steam being introduced through pipe 43, and the distillate being condensed in condenser 45.  Silica gel is also mentioned as a suitable adsorbent.