Patent GB-1103441-A (GB)
Title: Continuous sulfonation process
IPC: C07B45/02
Filed: 1965-01-15
Abstract: Organic compounds are sulphonated by feeding parallel concurrent streams of said compounds in the liquid phase and a gaseous mixture of SO3 and an inert diluent gas into a reaction zone formed between two cooled concentric cylindrical surfaces 1/8 -\ba1/2 inch apart and rapidly cooling the reaction mixture either in a downstream part of the reactor or in a separate cooler.  Preferably a cylindrical rotor is located concentrically between said surfaces, the clearance between the rotor and each of the surfaces being 5/1000 -\ba40/1000 inch (see Division B1). Numerous olefins having 8-20 carbon atoms, olefinically unsaturated acids; fatty alcohols having 8-20 carbon atoms, and ethoxylated derivatives thereof; ethoxylated alkyl phenols with C8- 16 alkyl groups; ethoxylated partial esters of polyhydric alcohols; and monocyclic and polycyclic aromatic hydrocarbons and C1- 20 alkyl derivatives thereof, are mentioned, as well as compounds already partly sulphonated. Cooling may be effected by recycling the reaction product through a heat exchanger and contacting this cooled material with the hot reaction product leaving the reaction zone in a quenching zone.  A plurality of reactors may be connected in parallel to a single cooling system, or if desired reactors may be connected in series. A part of the product may be recycled to the incoming organic reactant stream.  The concentration of SO3 in the gas is preferably 2-8% and the pressure of the gas entering is preferably 10-75 p.s.i.g. giving a velocity of 75-300 ft/second; the initial gas temperature is 90-125 DEG  F. Proportions of SO3 vary from 40% molar deficiency to 10% mole excess.  The liquid reactant may be admitted at 0 DEG  F.-135 DEG  F. Suitably the product may be neutralized with NaOH.  Examples describe (1) sulphonation of dodecyl benzene; (2) sulphation of lauryl alcohol; (3) sulphonation of a C8- 18 alkyl, alkyl benzene and C16- 18 tallow alcohol by the process described above; (4) and (5) sulphation of ethoxylated lauryl alcohol.ALSO:A reactor for sulphonating an organic liquid with a gaseous mixture of sulphur trioxide and an inert gas (see Division C2) comprises two cooled, concentric, cylindrical surfaces 1/8 - 1/2 in. apart, a rotor located concentrically therebetween and having a clearance with each of said surfaces 5/1000 - 40/1000 in., means for rotating the rotor, means for feeding the reactants in parallel concurrent streams to the space between said surfaces, and means for rapidly cooling the products.  As shown in Fig. 1 the concentric reactor walls 8, 9 are cooled by means of water jackets, gaseous SO3 with a diluent enters at the bottom of the apparatus and passes through annular opening 6\sv between the inner wall and the rotor 5, whilst liquid organic reactant enters through pipe 7 adjacent to wall 8 and through pipe 3, over rotor 5 and so is dispersed over wall 9.  The reaction mixture may be quenched by recycling cooled products to inlet 15 which are injected into said mixture through annular slot 10.  The product mixture is withdrawn at 11.  The rotor is driven by shaft 2 and motor 1.  In preferred embodiments the lower part of the rotor is of openwork form constructed of helical strips (Fig. 3, not shown) and in another embodiment (Figs. 4 and 5 not shown) a single liquid reactant stream enters through a line (3\sv) similar to line 3 in Fig. 1 and ducts (19) are provided in the rotor leading some of the liquid to the inner wall.  Two reactors may be connected in series so that the product from the first reactor is employed as quench liquid for the second, and conditions may be so arranged that SO3 used to excess in one reactor to form a product may be used up outside the reactor in mixing with another product formed with a deficiency of SO3 (Fig. 6 not shown).  The gas stream may pass through the reaction zone at 75-300ft./sec.  A plurality of jackets may be provided to give different cooling effects in different parts of the reactor, and baffles may be provided in the cooling jackets. In an example the rotor is rotated at 1750 r.p.m.