Patent GB-1036562-A (GB)
Title: Process for continuous concentration or separation of at least one component of a fluid mixture by contact thereof with solid particles
IPC: F28C3/12
Filed: 1963-05-15
Abstract: Hydrocarbons are separated or purified by selective sorption on a solid sorption agent arranged in a number of beds in a simulated countercurrent process, in which the solid is stationary and the fluid inlet and outlet points are moved, by introducing the feed into a fluid circulating through the beds, removing raffinate downstream while allowing a portion to circulate on to the next portion of the beds, further downstream effecting desorption with a desorbent at a temperature different from the sorption temperature, removing desorbate still further downstream while allowing a portion to circulate on to the next portion of the beds and thence into the sorption section and progressively moving all fluid inlet and outlet points downstream.  In Fig. 1 the sorbent is arranged in a number of interconnected beds B1-B20 each of the interconnections being connected to a control valve 2 the inner core of which is rotated to change the liquid inlet and outlet points producing the simulated counter flow effect.  The feed is introduced by line 4 <PICT:1036562/C4-C5/1> through the valve channel 5 into bed B4 joining fluid flowing from bed B5.  A raffinate is removed by valve channel 11 and line 12 while a portion is passed by line 13 and pump 3 into bed B20. In the case where desorption is effected at a higher temperature the fluid is heated in beds B20 and B19 by the desorbed sorbent which has previously been heated in the desorption section and is flowing effectively upstream into the sorption section.  In some cases the fluid leaving bed B19 is used as desorbent and for this purpose is taken by valve channel 23, heated in heater 27 and returned by valve channel 29 into bed B17.  An extraneous desorbent may alternatively be introduced. The desorbent may be heated again in heater 38 during its passage through the desorption section. Desorbate is removed by line 46 after bed B10, part of the fluid being allowed to flow through beds B9-B5 where it heats the sorbent almost to desorption temperature, while itself being cooled by the sorbent flowing effectively upstream; thence the fluid flows into the sorption section.  In certain embodiments desorption is effected at a lower temperature when heaters 27 and 38 are replaced by coolers and the heat exchanges effected in sections B20-B19 and B9-B5 are reversed. The beds of sorbent may be arranged one above the other or in a horizontal arrangement. The amount of circulating fluid passed from the sorption zone when an external desorbent is used and from the desorption zone may be such that interstitial fluid in the next following bed is incompletely, completely, or more than completely washed into the succeeding bed by the next change of inlet and outlet points.  Polar impurities are removed from petroleum fractions with silica gel or activated charcoal, aromatic hydrocarbons or olefins are separated from hydrocarbon mixtures with silica gel activated alumina or charcoal and straight chain hydrocarbons are separated using a molecular sieve. In another embodiment a solvent for aromatic hydrocarbons such as diethylene or triethylene glycol is carried in a porous solid such as silica gel, alumina or charcoal by means of which aromatic hydrocarbons are separated from mixtures and recovered by desorption at a lower temperature. In examples, propylene is selectively sorbed in liquid phase on a 5<\>rA molecular sieve to separate it from propane and the sieve desorbed with heated n-butane, aromatics are recoved from a reformed naphtha with silica gel desorbed with heated raffinate and bicyclic aromatics are recovered from a reformed kerosene with charcoal infused with triethylene glycol desorbed with cool n-hexane.ALSO:An ion-retentive resin is prepared by absorbing methacrylic acid in a porous anion exchange resin, containing trimethylbenzyl ammonium chloride groups in a styrene-divinyl benzene copolymer in an amount of about one mol of methacrylic acid per aromatic nucleus and polymerizing the methacrylic acid by heating to 90 DEG  C. at 6.8 atmospheres pressure. The product is used for purifying sea water.