Patent GB-731806-A (GB)
Title: Method and apparatus for carrying out chemical reactions in the liquid phase
IPC: C07C2/62
Filed: 1951-10-02
Abstract: Isoparaffinic hydrocarbons are reacted with olefins in the presence of a liquid acid catalyst to form branched chain hydrocarbons boiling in the gasoline range, free from polymerization products, by feeding to a confined reaction zone an emulsion of the liquid catalyst and the major portion of the isoparaffin feed, and a mixture of the remaining isoparaffin feed and recycled reactants and reaction products free from catalyst, discharging the emulsion and mixture through opposed coaxial nozzles to impinge on each other, introducing fresh olefin feed into the reaction zone either in admixture with the said mixture, or as a separate stream directed towards the region of impingement of the streams of emulsion and mixture, withdrawing liquid from the reaction zone and separating it into a heavy, catalyst component which is recycled with the isoparaffin feed and a lighter fractionable component part of which is withdrawn for product recovery, the major portion being recycled with the remaining isoparaffin, to the reaction zone.  As shown in Fig. 1, isobutane is fed at 29 and passed by pump 25 to a pipe 8 and header 9 in the lower portion of a reactor 1 which is divided into two chambers 1a, 1b by a <PICT:0731806/IV (b)/1> <PICT:0731806/IV (b)/2> plate 2 which carries a series of opposed nozzles 5.  Acid catalyst joins the isobutane feed either from line 30 or line 24b and is optionally emulsified in a device 26 or heated at 27.  The emulsion is discharged from chamber 16 through pipe 3 and nozzle 5 as a jet in chamber 1a.  Olefin feed, e.g. butylene, enters at 28 together with a minor amount of isobutane and, mixed with catalyst free liquid from line 20, enters the reaction chamber through pipes 7, 6, 6a and 4 to be discharged by the other nozzle 5.  Reaction products withdrawn at 10 are separated at 12 into a heavy catalyst containing component which passes down pipe 24 to join the main isobutane feed, and a lighter component, catalyst free and containing reaction products and excess isobutane reactant which leaves at 13.  The major portion of this is recycled by line 20 to take up the olefin feed from 28 and a minor proportion is passed through separators 14 and 15 to a fractionating column 18 for product recovery.  Catalysts employed may be sulphuric acid or mixtures thereof with phosphoric acid, hydrofluoric acid, or aluminium chloride boron fluoride complexes. 90 to 98 per cent sulphuric acid is preferred and reaction temperatures of 30 DEG  to 60 DEG  F. are specified.  The total feed may comprise 15 per cent butylene, 70 per cent isobutane, the olefin feed preferably containing at least 40 per cent butylene and the paraffin feed containing at least 85 per cent of isobutane.  The isobutane feed is preferably cooled to 25 DEG  to 40 DEG  F. in a cooler 32 and, to prevent freezing, a small amount of acid may be added at 30.  The olefin feed may also be at the same temperature.  The isobutane feed is preferably heated to 40 DEG  to 80 DEG  F. by heater 27 before entering the reactor through pipe 8. Alternatively, temperature control may be effected by allowing a portion of the materials fed to the reaction vessel to vaporize, and after recompression, recirculating them to produce an auto-refrigeration effect at the point of contact of the reactants in the reactor. The retention time in the zone X between the nozzles may be from 0.10 to 10 seconds and the residence time in the reactor 0.5 to 5 minutes.  In a modification, Fig. 2, the emulsion of catalyst and isoparaffin from chamber 16 passes through pipe 3 to be discharged at nozzle 5 whilst recycled reactants enter pipes 7, 6a, 4 and are discharged through the other nozzle 5.  The olefin is then fed from pipe 32 to a pipe 31 terminating at a point between the nozzles 5.  The invention is applicable to the use of fast reacting olefins such as propylene, amylene and isobutylene, whilst as paraffins, isopentane may also be used.  Specification 731,815 is referred to.ALSO:Liquid reactants are contacted in a reaction zone in the presence of a liquid catalyst, immiscible therewith by emulsifying the liquid catalyst with a major portion of the least reactive of the fresh feed materials, mixing the remaining and minor proportion of said least reactive reactant with a major portion of the <PICT:0731806/III/1> <PICT:0731806/III/2> reactant materials withdrawn from the zone after contact therein and separation of catalyst, and injecting said emulsion and mixture into the reaction zone as coaxially opposed jetted streams impinging on each other within a body of said materials maintained in the zone, and introducing the most reactive material of the fresh reactant feed either in admixture with said stream of the mixture of the least reactive component and the recycled reactant materials or as a separate stream directed towards the region of impingement of the streams of emulsion and mixture.  The method is particularly applicable to the reaction of isoparaffinic hydrocarbons with olefines to form branched chain saturated hydrocarbons boiling in the gasoline range, and to avoid undesired polymerization reactions.  As shown in the Figure, a closed reactor 1 is divided into two chambers 1a, 1b by a transverse plate 2 through which a series of pairs of pipes 3 and 4 pass, terminating in opposed nozzles 5.  The least reactive reactant, e.g. isobutane is fed at 29 and passed together with the liquid catalyst, such as sulphuric acid or mixtures thereof with phosphoric acid, hydrofluoric acid or complexes of aluminium chloride and boron fluoride from pipe 30, through a punch 25 and line 8 to the lower chamber 1b by a header 9.  If desired this feed may be by-passed through a heat-exchanger 27 and emulsification enhanced by subdividing the feed and discharging it as opposed jets in a device 26 before entering pipe 8.  This portion of the feed fills the chamber 1b and passes through plate 2 by pipe 3 to be discharged through nozzle 5.  The most reactive component is fed at 28, mixed with recycled reactants (see below) from pipe 20 and passed through pipes 7, 6a and 4 to the other nozzle 5.  Reaction products are withdrawn at 10 and passed through a separator 12 where the liquids are separated into a heavy component, consisting of catalyst which may be in part withdrawn at 24a and replenished at 24b, and a lighter component consisting of a fractionable mixture including reaction products and the excess of one of the reactants.  The lighter component withdrawn at 13 is in part passed to additional separators 14 and 15 and to a fractionating tower 18, whilst part is recycled through pipes 20 and 7 to the reaction zone.  The heavy component passes through line 24 to be mixed with the isobutane feed at 31 and is recycled to the reactor.  In a modification, Fig. 2, the emulsion of catalyst and least reactive reactant from chamber 1b passes through pipe 3 to be discharged at nozzle 5 whilst recycled reactants enter pipes 7, 6a, 4 and are discharged through the other nozzle 5. The most reactive component, e.g. the olefine, is led from pipe 32 to a pipe 31 terminating at a point p  between the nozzles 5.  The reaction and feed temperatures are controlled as shown by heat exchangers 23, 32, 27, but if desired a portion of the materials supplied to the reaction vessel may be vaporized therein and after recompression, recirculated to produce an auto refrigeration effect at the point of contact of the reactants in the reactor. Specification 731,815 is referred to.