GB1569061A

GB1569061A - Sulphonation method and apparatus therefor

Info

Publication number: GB1569061A
Application number: GB701/78A
Authority: GB
Original assignee: Kao Corp; Kao Soap Co Ltd
Current assignee: Kao Corp
Priority date: 1977-01-17
Filing date: 1978-01-09
Publication date: 1980-06-11
Also published as: FR2377379A1; BE862913A; DE2800788A1; NL7800554A; IT7819310A0; ES465901A1; IT1092741B; FR2377379B1; JPS5390219A

Description

(54) SULFONATION METHOD AND APPARATUS THEREFOR (71) We, KAO SOAP CO. LTD.. a Japanese Company. of 1. I-chome, Nihonbashi Kayabacho, Chuo-ku, Tokyo, Japan, do hereby declare the invention. for which we pray that a Patent may be granted to us. and the method by which it is to be performed, to be particularly described in and by the following statement: The present invention relates to a method and an apparatus for sulfonating organic compounds that are liquid at ambient temperature or at the reaction temperature, such as alcoholic hydroxy compounds, compounds having a double bond capable of being sulfonated and aromatic hydrocarbons.

The reaction of liquid organic materials with sulfur trioxide is usuallv called "sulfona- tion" even though the products of the reaction are either sulfates or sulfonates. depending on the specific liquid organic starting material used. The term sulfonation't and derivatives thereof are used in the following description and claims in a generic sense to include both true sulfonation and true sulfation.

More particularly, the invention relates to an improved method and apparatus for performing sulfonation by reacting a liquid organic compound such as those mentioned above with sulfur trioxide gas diluted with air or other inert gas.

Reactions using concentrated sulfuric acid. fuming sulfuric acid or chlorosulfonic acid, as a sulfonating agent, are conducted in a liquid-liquid mixture system. In many cases. the reactions are carried out by a batch process. using a large amount of the sulfonating reagent. However, the conventional method is disadvantageous because the quality of the reaction products varies from batch to batch and considerable amounts of unwanted inorganic compounds are contained in the reaction product.

Recently, sulfur trioxide (SO3) gas had been used as a sulfating or sulfonating agent.

Various processes for continuously conducting a liquid-gas phase sulfonation reaction, using sulfur trioxide gas. have been worked on a commercial scale. However. the prior art processes using S03 gas have various disadvantages because of the complexities of the manufacturing techniques.

For example, a tubular reaction system such as disclosed in U.S. Patent No. 2 923 728.

Japanese Patent Publication No. 374()7/72 and Japanese Patent Publication No. 8087/73, is useful for preparing sulfonated products at small volumetric production rates. but this system is not suitable for preparing sulfonated products at large volumetric production rates. More specifically. if it is desired to produce a large quantitv of sulfonated product by using one reaction tube. it is necessarv to increase the diameter of the tube. However. if the diameter of the reaction tube is increased excessively. difficulties are encountered in cooling (removing the exothermic heat of the reaction) the material undergoing sulfonation in the reaction tube. When the reaction is performed by a one-stage reaction using a plurality of reaction tubes arranged in parallel. it is necessarv to precisely control the liquid-gas ratio in each reaction tube. This process is not advantageous from an industrial viewpoint.

When a thin film of liquid organic reactant is raised vertically upwardly by an upwardly flowing, SO3-containing, gas stream. as disclosed in Japanese Patent Publication No.

37407/72, the amount of the starting liquid organic reactant fed in increases substantially in proportion to the square of the tube diameter. but the cooling area of the tube wall increases only in direct proportion to the tube diameter. Accordingly. the capacitv for adequately cooling the reaction zone becomes insufficient as the tube diameter is increased and, consequently, the reaction temperature becomes excessively high. thereby causing instability of the colour of the reaction product. Further. the thickness of the liquid film increases substantially in proportion to the tube diameter. which causes concentration and temperature gradients to be formed in the liquid film, which in turn creates conditions which make it very difficult to minimize unwanted side reactions.

The present invention relates to a sulfonation method and apparatus suitable for the production of large volumes of sulfonated products.

According to this invention we provide a continuous process for sulfonating a liquid organic compound with a ga containing 1 to 20% by volume of SO3 by a two-stage reaction, wherein the first stage is conducted by introducing the organic compound upwardly and the SO3 - containing gas concurrently into lower portions of a plurality of vertical first-stage reaction tubes, the velocity of the gas being at least 20 m/sec. the reaction products formed by the first stage reaction are collected and cooled by passing them in a combined stream downwardly through a cooling cylinder. and then the second stage is conducted by introducing the cooled combined reaction products upwardly and fresh COR - containing gas concurrently into a lower portion of a single second-stage reaction tube, and wherein during both stages the liquid material forms a thin annular film on the inside of the reaction vessel.

The present invention is similar to the process disclosed in U.S. Patents Nos. 4086256 and 4097242 in the point that the reaction is carried in two stages. According to the present invention. however, unexpectedly improved results are achieved by conducting the first stage reaction using a plurality of reaction tubes connected in parallel. cooling a single stream comprised of the combined reaction products of all of the first stage reaction tubes in one intermediate cooling stage and then conducting the second stage reaction bv using a single second stage reaction tube. When the first stage reaction is carried out by using a multiple-tube system, because it is not necessary to completely convert l()()'ic of the starting organic compound to the corresponding sulfonated product in the first stage reaction. there is attained the advantage that the liquid-gas molar ratio need not be strictly controlled in each of the first stage reaction tubes. Rather. the overall liquid-gas molar ratio for the entire process can be closely controlled. as a whole, by controlling the sum of the amounts of SO3 fed into the first stage and second stage reactions. For example. when an average conversion of 80% is to be attained in the first stage reaction and the remaining conversion of 20% is to be performed in the second stage reaction, even if the conversion is different in the respective first stage reaction tubes. namely, if. for example. different conversions of 78%. 82'17s and the like are attained in the respective tubes of the first stage reaction, because the reaction products from the respective first stage tubes are combined into a single stream and the resulting single stream comprising a mixture of all of the reaction products from all of the first stage tubes is subjected to a common second stage reaction in a single second stage reaction tube. any differences of the conversions achieved in the respective first stage reaction tubes are averaged out by combining all of the first stage reaction products so that such differences do not have a bad effect on the quality of the final product.

The sulfonation reaction is a vigorous exothermic reaction and the hue of the reaction product is greatly influenced by the cooling efficiencv during the reaction. It is apparent from an engineering viewpoint that as the tube diameter is increased. the abilitv of the cooling system to remove the reaction heat does not increase as fast as does the amount of reaction heat that is generated. because the increase of the flow rate is larger than the increase of the tube wall area. Accordingly. if tubes having a small diameter. in order to assure a sufficient cooling effect, are used in the first stage reaction, discoloration of the product caused bv excessive elevation of the temperature of the reaction liquid can be more effectively prevented.

In the above Patent. there is disclosed a method and apparatus in which the reaction products of the first stage reaction tubes are collected to form a single stream and that stream is flowed downwardly. together with fresh SO1-containing gas. through a central cylinder which acts as the second stage reaction zone. In contrast. in the present invention the central cylinder is used as an intermediate cooling zone. so that the temperature of the single stream that subsequently enters the second stage reaction zone is significantly lowered and thereby the disadvantage otherwise caused by the use of a single second stage reaction tube, namelv, insufficient cooling. can be remarkably reduced.

Brief description of the drawings Figure 1 is a vertical sectional view of an embodiment of apparatus according to the present invention.

Figure 2 is a sectional view taken along the line A-A of Figure 1.

An embodiment of the sulfonation apparatus of the present invention will now be described by reference to the accompanying drawing.

As shown in Figure 1, the first stage reaction vessel comprises three concentric. vertical cylinders 1, 2 and 3, each of circular cross-section. In the outer annular space defined between cylinders 2 and 3, there are provided a plurality of reaction tubes 4. here eight tubes, which are equidistantly spaced from each other and are arranged in a circular array so that the distances from the central longitudinal axis of the cylinder 1 to the central longitudinal axis of each of the tubes 4 is equal for all the tubes 4. The ends of the tubes 4 are fixed to tube plates 5 and 6. The tube plate 6 has an annular vertical passage 7 extending in the axial direction of the tube 4 and a second horizontal passage 8 extending in a direction perpendicular to said axial direction through the side of the tube plate 6. A nozzle 9 extends vertically through the passage 7 and into the interior of the tube 4 at the lower end thereof.

The nozzle 9 is substantially concentric with the tube 4 and communicates with the lower end thereof. Accordingly. there are formed two flow paths communicating with the interior of the tube 4, namely, a first flow path extending through the interior of the nozzle 9 from below the tube plate 6 and a second flow path extending from the passage X through the annular space between the pipe 4 and the nozzle 9.

To the top end of each of the tubes 4. there is attached the radially outer leg of a reversely curved conduit 10 by means of a flange 11. The radially inner leg of the curved conduit 10 extends downwardly through a cover plate 12 which covers the central opening of the tube plate 5. The upper end of the innermost cylinder 1 has an inverted frusto-conical liquid-collecting trough 13 extending upwardly therefrom. The radially outer, upper edge of the trough 13 is fixed to the inner wall of the intermediate cylinder 2 adjacent the upper end thereof. The liquid streams and gas streams from all of the tubes 4 are collected in the trough to form a combined single liquid stream and a combined single gas stream.

The tube plate 6 has a dome-shaped cover plate 15 secured to the underside thereof. The cover plate 15 defines an enclosed space 14 below the lower tube plate 6. A port 16 is provided at the lower portion of the cover plate 15 for supplying SO3-containing gas to the space 14 and thence through nozzles 9 to all of the reaction tubes 4 at the lower ends thereof. The lower portion of the innermost cylinder l penetrates through the tube plate 6 and the cover plate 15 to provide a downwardly extending flow path for the combined reaction product stream that flows downwardly from the trough 13 and through the cylinder 1.

An inlet nozzle 18 for cooling water and an outlet nozzle 19 for cooling water are secured to the outermost cylinder 3 for flowing cooling water into the annular space between cylinders 2 and 3. An inlet nozzle 20 for cooling water and an outlet nozzle 21 for cooling water penetrate through the cylinder 3 and are attached to the cylinder 2 for flowing cooling water into the annular space between cylinders 1 and 2.

As shown in Figure 1, the second stage reaction vessel comprises a vertical pipe 25 having a cylindrical cooling jacket 27 surrounding same. The pipe 25 is connected to the lower end of cylinder 1 by a reversely curved conduit 30. A central pipe 22 for feeding SO-containing gas is encircled by an outer pipe 23 having a nozzle 24 for feeding an annular stream of inert gas. The two pipes 22 and 23 extend upwardly into the lower end of tube 25 for feeding separate streams of SO3-containing gas and inert gas coaxiallv into the lower end of said tube 25, wherein the annular stream of inert gas that is fed in from outer pipe 23 surrounds the central stream of SO-containin,g gas that is fed in through pipe 22. An annular space is defined between the upper end of tube 23 and the lower end of pipe 25 so that the liquid reaction product and the gas flowing through conduit 30 can flow upwardly, in the form of an annular stream, into the lower end of tube 25 and surrounding the annular stream of inert gas that is fed in through outer pipe 23.

A cooling water inlet nozzle 28 and a cooling water outlet nozzle 79 are attached to the jacket 27.

In the illustrated embodiment. eight tubes 4 are used. but in the apparatus of the present invention, the number of the pipes 4 can optionallv be changed.

The operation of the above-mentioned apparatus will now be described.

A liquid organic compound is fed through each of the passages 8 at a predetermined constant rate by means of a metering pump or the like. In the illustrated embodiment, because eight tubes 4 are used. eight passages X are provided and the organic compound is fed into the lower ends of the tubes 4 at substantially equal and constant rates.

Simultaneously. an SO3-containing gas is fed into the port 16. The SOa-containing gas is introduced into the lower ends of all of the tubes 4 through the nozzles 9 at a velocity effective to aspirate and lift the organic compound flowing through the annular clearances between the nozzles 9 and the tubes 4 whereby said organic compound rises in the tubes 4 in the form of rising thin films of the organic compound moving upwardly on the inner walls of the tubes 4. The flow rates of the liquid organic compound and the SO-containing gas are controlled so that the amount of SO fed into tubes 4 is less than the stoichiometric amount, relative to the liquid organic compound.

The organic compound reacts with the SO a gas in the tubes 4 in a known manner to form a partially sulfonated product. The formation of a rising thin film of the organic material by means of an SO3-containing gas stream is described in U.S. Patent No. 4102911. The partially sulfonated products exiting from the upper ends of tubes 4 flow through the curved pipes 10, are collected and combined to form a single liquid stream in the liquid-collecting trough 13 and the combined single liquid stream is flowed downwardly in the form of an annular film on the inner wall of the cylinder 1. The gas streams exiting from the upper ends of tubes 4 likewise are combined in the trough 13 and flow downwardly in cvlinder 1 substantially in the form of a central gas stream surrounded by the annular film of the liquid. During this downflow movement of the annular liquid film and the central gas stream in cylinder 1, the liquid organic compound is cooled by indirect heat exchange with the cooling water flowing in the annular space between cylinders 1 and 2. The amount of cooling of the liquid material that occurs as it flows downwardly in cylinder 1 is selected, taking in consideration the amount of heat that will be generated in the second reaction stage, so that the amount of heat removed in cylinder 1 in combination with the amount of heat removed in reaction tube 25 is sufficient to prevent the temperature of the liquid material flowing through tube 25 from rising to a temperature at which appreciable coloring or charring of the liquid will occur. This can be determined bv routine experimentation. In general, the temperature of the liquid material is reduced in an amount of from 60-I()00C before cooling to 30-50"C after cooling during its passage through the cylinder 1.

The single liquid stream and the single gas stream that flow downwardly through cylinder 1 then pass through the curved pipe 30 and rise in the pipe 25. wherein thev are contacted by fresh SO-containing gas fed from the nozzle 22. An inert gas is introduced from the nozzle 24 to surround the SOx-containinq gas stream whereby to prevent undesirable discoloration caused by an excessively vigorous reaction in the zone adjacent to the upper end of the nozzle 22. The single liquid stream is flowed upwardly through the upwardly extending leg of pipe 30 by means of the driving force of the gas stream that accompanies the liquid stream. Even if the velocitv of the gas stream may not be sufficient to maintain the liquid stream in the form of a thin film of uniform thickness in the lowermost portion of reversely curved pipe 30, the kinetic energy of the gas stream will be sufficient to force the liquid upwardly through the annular zone between tube 23 and the internal wall of the upwardly extending leg of pipe 30 so that the liquid is in the form of an annular film of substantially uniform thickness when it enters the lower end of tube 25. The gas streams entering through pipes 22 and 23 are then effective to raise the liquid film along the wall of the reaction tube 25 in the same manner as occurs in tubes 4. The operation that occurs in pipe 25 is substantially the same as the operations that occur in tubes 4 as described previously. Thereby, sulfonation of the liquid is substantially completed by the time the liquid exits from the upper end of tube 25.

The organic compound (now substantially completelv sulfonated) and the gas are discharged from the top end 26 of the tube 25. The discharged mixture of organic compound (sulfonation product) and the gas is subjected to gas-liquid separation in the Cyclone (Reg. T.M.) or the like. The liquid sulfonation product is then neutralized to recover the desired product. The liquid-gas separation using a Cyclone and the neutralization can be performed by conventional procedures. and accordingly. these steps are not shown in the drawing.

Because the sulfonation reaction is a vigorous exothermic reaction, in the first stage reaction occurring in the tubes 4 the increase of the temperature of the organic compound is controlled by introducing cooling water from the nozzle 18. In the second stage reaction that occurs in the tube 25, the increase of the temperature of the organic compound is controlled by introducing cooling water from the nozzle 'X. The cooling water streams are discharged from nozzles 19 and 29. respectively. It is conventional practice to externally cool thin-film sulfonation reaction zones.

A distinctive feature of the present invention is that the partially sulfonated organic liquid is cooled between the first stage reaction in the tubes 4 and the second stage reaction in the tube 25 by passing the liquid reaction product formed in the first stage reaction tubes 4 through the intermediate cylinder wherein the liquid reaction product is effectively cooled. Cooling of the intermediate cooling cylinder I is accomplished by introducing cooling water from the nozzle 20 and discharging it from the nozzle 21.

The method of introduction of cooling water is not limited to the above-mentioned method and other methods can be adopted. For example. cooling water may be introduced from the nozzle 19 and discharged from the nozzle 18, or if the pipes 4, 25 and 1 are long, a plurality of introduction and discharge openings for cooling water can be used along the lengths thereof.

According to the present invention, in the first and second reaction stages, the starting liquid organic material and a stream of air or other inert gas containing 1 to 20% by volume of SO3 are continuously introduced through a vertically extending pipe or jacket-equipped pipe from the lower end thereof. The velocity of flow of the gas in the pipes 4 and pipe 25 is set at an appropriate value exceeding 2() misec. so that the gas. per se, exerts a driving force effective to cause a rising annular thin film of the liquid organic reactant to be formed on the wall of the reaction tube. Mixing of the reactants and cooling of the reaction mixture can be accomplished effectively as the liquid organic reactant flows upwardly on the inner wall of the tube. The mixing that occurs when the annular thin film rises vertically against the effects of gravity causes the reaction to advance in such a state that the occurrence of side reactions is remarkably reduced. However. if the gas flow rate exceeds 120 m/sec. the liquid film is excessively agitated so as to form an atomized mist of liquid in the gas. If this occurs, the gas-liquid contact becomes excessive. the reaction speed is excessively fast. with the result being that it is impossible to control the reaction temperature. Furthermore. the pressure drop becomes large. Accordingly. an excessively high gas speed is not preferred from the economical viewpoint.

The gas-liquid contact is initiated at the point whereat the gas stream is jetted from the nozzle, such as nozzles 9 and nozzle 22. It also is possible to employ a method in which the starting liquid organic material is jetted in advance together with an inert gas to form a rising annular thin film in the reaction tube, and then, SO, gas or a gas containing SO at a high concentration is introduced to effect the gas-liquid contact. This procedure is described in U.S. Patent No. 2 923 728 and reference should be made thereto for further details of this procedure.

The conditions for forming a rising annular thin film are adjusted depending on the physical properties of the particular starting organic liquid that is used, the SO-containing gas and the properties of the intermediate reaction product. but when organic compounds treated in the present invention, such as those exemplified hereinafter, are employed. if the gas flow rate is higher than 20 m/sec. a rising annular thin film is formed. The annular film not only rises along the pipe wall but it is agitated and swirls on the wall surface thereof.

In the present invention, the first stage reaction, which has a significant influence on the discoloration of the product. is thus conducted in the form of a rising liquid thin film of the liquid organic reactant. Effective cooling of the first stage reaction is accomplished owing to the use of a plurality of relatively small diameter tubes 4 arranged in parallel. Accordingly, the quality of the sulfonation product can be remarkablv improved. The second stage reaction is for the purpose of completing the sulfonation. The second stage reaction is inherently a less vigorous reaction and less exothermic heat of reaction is generated because the major proportion of the reaction was completed in the first stage reaction, Thus, sufficient cooling can be effected in the second stage reaction tube 25 even though it is of larger diameter than the first stage reaction tubes 4 and the amount of liquid organic material that flows therethrough is larger. Moreover. the reaction product of the first stage is cooled in the intermediate cooling cylinder I disposed in the first stage reaction vessel, so that the liquid material is prevented from becoming heated excessively.

The diameter of cylinder 1 is larger than the diameters of tubes 4 so that the single liquid stream obtained by combining the streams from tubes 4 will flow downwardly along the cylinder 1 as a thin film. The film that flows along cylinder 1 can be thicker than the films that flow along tubes 4. For example, the films that flow upwardly along tubes 4 can have a thickness of 0.012 to 0.12 cm and the film that flows downwardly along cylinder 1 can have a thickness of up to about 0.5 cm. The diameter of tube 4 is substantially the same as the diameter of cylinder 1.

It is preferred that the reaction rates in the first and second stage reactions are arranged so that the conversion (% completion of the sulfonation reaction) in the first stage reaction in the tubes 4 is from 60 to 95%, especiallv 75 to '35C/C Accordingly. the ratio of (1) the amount of the SO3-containing gas introduced into the tubes 4 to (2) the amount of the starting organic compound is selected so that such amount of conversion is attained in the first stage. The sum of the amounts of S01 supplied in both the first and second stages, to the amount of the starting organic compound. is preferably selected so that the total S03 for the entire process is from about 1.0 to 1. 1 moles, per mole of the starting organic compound.

As the liquid organic compounds that can be sulfonated according to the present invention, there can be used any compoounds that are liquid at room temperature or the reaction temperature and that react with SO3 gas. Such sulfonateable compounds are well-known materials which have been sulfonated in the prior art. 'Ibe conditions of temperature. pressure etc. employed in the sulfonation reaction are the well-known conventional conditions. For example, the following typical sulfonateable compounds can be used in the present invention: (1) Straight-chain or branched-chain alcohols having 8 to 20 carbon atoms, ethylene oxide adducts thereof containing 1 to 10 moles of ethylene oxide and mixtures thereof.

(2) Monoalkyl benzenes having an alkyl side chain of 8 to 25 carbon atoms and mixtures thereof.

(3) Straight-chain olefins having 6 to 25 carbon atoms and mixtures thereof.

(4) Alkylene oxide adducts to active hydrogen-containing compounds such as alkylphenols containing 1 to 10 moles of ethylene oxide and in which the alkyi chain has 8 to 18 carbon atoms.

(5) Fatty acid alkanolamides from fatty acids having 10 to 20 carbon atoms.

(6) Fatty acids having 8 to 20 carbon atoms. mixtures thereof. ethylene oxide adducts thereof, esters of such fatty acids with lower alkanols and mixtures thereof.

(7) Esters of fatty acids having X to 20 carbon atoms with polyhydric alcohols. alkylene oxide adducts thereof and mixtures thereof.

Of course, mixtures comprising two or more of the foregoing kinds of compounds can be sulfonated according to the present invention.

As the SO-containing gas there is employed a gas formed by evaporating stabilized sulfuric anhydride (for example, a product sold under Registered Trade Mark "Sulfan") and diluting the resulting gas with air or other inert gas or a so-called converter gas formed by converting a sulfur combustion gas. as it is, or after it has been diluted. The SO3 concentration in the SO3-containing gas is 1 to 20- by volume, especially 2 to 10% by volume, as is conventional in the prior art.

Example Sulfonation was conducted in a sulfonation apparatus. as illustrated in the drawing. using eight tubes 4 each having an inner diameter of 25 mm and a length of 3 m. an intermediate cooling cylinder 1 having an inner diameter of 81 mm and a length of 4 m (the first stage reaction) and one tube 25 having an inner diameter of 81 mm and a length of 8 m (the second stage reaction). The results obtained are shown in Table 1. In comparative tests, (1) no intermediate cooling was done in cylinder I in the first stage reaction vessel. but rather the SO3-containing gas for the second stage reaction was introduc

TABLE 1 Present Compari- Compari- Compari Invention son 1 son 2 son 3 Flow rate (Kg/hr) of dodecyl benzene 500 500 500 501 (molecular weight = 242) Flow rate (Nm /hr) of (SO3 + air) 1164 1164 1165 1164 SO3 Concentration (%) 4.0 4.0 4.0 4.0 First stage/second stage volume 75/25 76/24 - distribution ratio of SO3 + air mixture Total Conversion (%) of starting material 98.2 98.1 98.2 97.9 Hue of neutralized reaction 12 25 29 40 product (Klett number) Flow rate (Kg/hr) of lauryl 245 245 245 178 alcohol (molecular weight = 204) Flow rate (Nm /hr) of (SO3 + air) 1164 1164 1164 1075 SO3 Concentration (%) 2.32 2.32 2.32 1.81 First stage/second stage volume 85/15 84/16 - distribution ratio of SO3 + air mixture Total Conversion (%) of starting material 96.9 96.8 96.7 96.5 Hue of neutralized reaction 8 10 52 40 product (Klett number) Note The reaction product was neutralized, and an aqueous solution containing 10e of the effective component was prepared and the absorbance at 420 mF was determined with I-cm cell. The Klett number was obtained by multiplying the determined value by 1000.

Claims

WHAT WE CLAIM IS:

1. A continuous process for sulfonating a liquid organic compound with a gas containing 1 to 20% by volume of SO1 by a two-stape reaction, wherein the first stage is conducted by introducing the organic compound upwardly and the SO - containing gas concurrently into lower portions of a plurality of vertical first-stage reaction tubes. the velocity of the gas being at least 20 m/sec. the reaction products formed by the first stage reaction are collected and cooled by passing them in a combined stream downwardly through a cooling cylinder, and then the second stage is conducted by introducing the cooled combined reaction products upwardly and fresh SO;; - containing gas concurrently into a lower portion of a single second-stage reaction tube. and wherein during both stages the liquid material forms a thin annular film on the inside of the reaction vessel.

2. A process according to Claim 1. consisting essentially of the steps of: simultaneously continuously flowing an outer annular stream consisting of said liquid organic reactant and an inner gaseous stream consisting of the SOt - containing gas, vertically upwardly into the lower end of each of a plurality of separate elongated first stage reaction tubes, so that the inner and outer streams flow in concurrent substantially parallel vertically upwardly directed flows into and through said first-stage reaction tube. said inner and outer streams flowing upwardly through said first-stage reaction tube in gas-liquid contact, said outer stream of liquid reactant forming a continuous thin annular upwardly rising outer liquid film of substantiallv uniform thickness on the wall of said first-stage reaction tube and extending the entire' length thereof, said inner gaseous stream flowing inside of said liquid film upwardly through the entire length of said first-stage reaction tube and having a flow velocity in the range of from about 20 m./sec. to about 120 m./sec., said inner gaseous stream uniformly contacting said annular liquid film over its entire inner surface in said first-stage reaction tube to effect upward movement and mixing of said liquid film whereby the organic reactant and the gaseous sulfur trioxide are mixed and contacted with each other to effect the reaction. and rapidlv extracting heat from the resultant reaction mixture as it passes upwardly through said first-stage reaction tube by contacting the exterior surface of said reaction tube with cooling liquid: continuously removing said liquid streams and said gas streams from the upper ends of all said first-stage reaction tubes, combining all of said liquid streams into a single combined liquid stream and combining all of said gas streams into a single combined gas stream and flowing said single combined liquid stream and said single combined gas stream into the upper end of a single elongated vertical cooling cylinder to form a single annular film of said liquid stream on'the internal wall of said cooling cylinder and a single stream of said gas inside said annular film, and without supplying additional sulfur trioxide gas into said cooling cylinder, flowing said liquid and gas streams in concurrent substantially parallel vertically downwardly directed flow into and through said cooling cylinder, said streams flowing downwardly through said cooling cylinder in gas-liquid contact with said liquid stream forming a continuous thin annular downwardly flowing outer liquid film of substantially uniform thickness on the wall of said cooling cylinder and extending the entire length thereof, said gas stream flowing inside the liquid film downwardly through the entire length of said cooling cylinder, and rapidlv extracting heat from the streams as same pass downwardly through said cooling cylinder by contacting the exterior surface of said cooling cylinder with cooling liquid: then continuously flowing into a single elongated vertical cylindrical second-stage reaction tube an outer annular stream consisting of said single liquid stream and said single gas stream discharged from said cooling cylinder and an inner gaseous stream consisting of a mixture of one to 20% by volume of sulfur trioxide and the balance a gaseous inert diluent, said outer stream being flowed vertically upwardly into the lower end of said second-stage reaction tube, said inner stream being flowed vertically upwardly into said lower end of said second-stage reaction tube, said inner and outer streams flowing in concurrent substantially parallel vertically upwardly directed flow into and through said second-stage reaction tube, said inner and outer streams flowing upwardly through said second-stage reaction tube in gas-liquid contact, said liquid reactant forming a continuous thin annular upwardly rising outer liquid film of substantially uniform thickness on the wall of said second-stage reaction tube and extending the entire length thereof, said inner gaseous stream flowing inside of said liquid film upwardly through the entire length of said second-stage reaction tube and having a flow velocity in the range of from about 2( m.lsec. to about 120 m./sec. said inner gaseous stream uniformly contacting said annular liquid film over its entire inner surface in said second-stage reaction tube to effect upward movement and mixing of said liquid film whereby the organic reactant and the gaseous sulfur trioxide are mixed and contacted with each other to effect the reaction. and rapidly extracting heat from the resultant reaction mixture as it passes upwardly through said second-stage reaction tube by contacting the exterior surfaces of said second-stage reaction tube with cooling liquid the sum of the amounts of sulfur trioxide supplied to said first-stage reaction tubes and said second-stage reaction tube being being 1.0 to 1.1 moles per one mole of said liquid organic reactant fed into said first-stage reaction tubes and the amount of sulfur trioxide supplied to said first-stage reation tubes being selected so that the sulfomltion or sulfation reaction is from 60 to 95% completed in the first stage reaction tubes: separating the liquid phase from the gaseous phase after same have left the top of said second-stage reaction tube and recovering the reaction product from the liquid phase.

3. A process as claimed in Claim 2 in which the amount of sulfur trioxide gas fed into said first-stage reaction tubes is an amount such that the sulfonation or sulfation reaction is 75 to 95% completed in the first stage reaction tubes.

4. A process as claimed in Claim 2 in which said gaseous streams fed to said first-stage reaction tubes and said second-stage reaction tube contain from 2 to 10cue by volume of sulfur trioxide.

5. A process as claimed in Claim 2 in which a single current of gas consisting of a mixture of about one to 20% by volume of sulfur trioxide and the balance a gaseous inert diluent is fed into a single chamber located below the lower ends of said first-stage reaction tubes and said single gaseous current flows from said chamber through separate nozzles to form said inner gaseous streams which flow vertically upwardly into the lower ends of said first-stage reaction tubes.

6. A process as claimed in Claim 2 in which said liquid organic reactant is a straight-chain or branched-chain alcohol having 8 to 2() carbon atoms. ethylene oxide adducts thereof, or mixture thereof.

7. A process as claimed in Claim 2 in which said liquid organic reactant is an alkylbenzene having an alkyl side chain of X to 25 carbon atoms. or mixture thereof.

8. A process as claimed in Claim 2 in which said liquid organic reactant is a straight-chain olefin having 6 to 25 carbon atoms. or mixture thereof.

9. A process as claimed in Claim 2 in which said liquid organic reactant is an alkylene oxide adduct of an alkylphenol having an alkyl side chain of 8 to 18 carbon atoms and containing 1 to 10 moles of ethylene oxide. or mixture thereof.

10. A process as claimed in Claim 2 in which said liquid organic reactant is a fatty acid alkonolamide of a fatty acid having 10 to 20 carbon atoms. or mixture thereof.

11. A process as claimed in Claim 2 in which said liquid organic reactant is a fattv acid having 8 to 20 carbon atoms ethylene oxide adducts thereof. mixtures of said fattv acids and ethylene oxide adducts. lower alcohol esters of said fatty acids. or mixture of said esters.

12. A process as claimed in Claim 2 in which said liquid organic reactant is a polvhydric alcohol ester of fatty acids having 8 to 20 carbon atoms. alkylene oxide adducts thereof or mixtures thereof.

13. A sulfonation apparatus when used in the process of any preceding claim comprising a first stage reaction vessel having in the lower portion thereof a first stage reaction zone including an inlet for introducing an organic compound and a plurality of first-stage reaction tubes having curved upper portions. an intermediate cooling cylinder having a liquid-collecting device at the upper end thereof communicating with said curved upper portions of said first-stage reaction tubes. and a second-stage reaction vessel comprising one second-stage reaction tube. an outlet disposed in the lower portion of said cooling cylinder being connected to the lower portion of said second stage reaction vessel.

14. An apparatus when used for reacting a liquid organic reactant with sulfur trioxide gas in accordance with any of Claims I to 12 comprising: a first-stage reaction zone comprising a plurality of vertically positioned first-stage reaction tubes each having at the lower end thereof central inlet means for feeding a stream of a mixture of sulfur trioxide gas and inert gas upwardly into the central region of said tube and an outer annular inlet surrounding said central inlet means and isolated therefrom for feeding an annular stream of said liquid organic reactant upwardly along the internal wall of the tube, said inlets terminating adjacent the lower end of the tube and the remainder of the cylinder being open to permit concurrent upward parallel flow and contact between said steams to effect the reaction; means for cooling the external surface of each of the first-stage reaction tubes along substantially the entire length thereof to remove the exothermic heat of reaction generated therein by contact between said organic reactant and said sulfur trioxide: a cooling zone consisting essentiallv of a single vertically positioned cooling cylinder having a collecting trough at the upper end thereof. a discharge conduit at the lower end thereof and means for cooling the external surface of said cooling cylinder along the length thereof to remove heat therefrom: each of said first-stage reaction tubes having a pipe extending from the upper end thereof to said collecting trough of said cooling cylinder so that the entirety of the gas and liquid streams exiting from all of the first-stage reaction tubes are combined and fed into the upper end of said cooling cylinder, said cooling cylinder being free of means to supply sulfur trioxide gas thereto; and a second stage reaction zone having a single vertically positioned second-stage reaction tube having at the lower end thereof inlet means for feeding a stream of a mixture of sulfur trioxide gas and inert gas upwardly into the central region of said second-stage reaction tube and an outer annular inlet surrounding said inlet means and isolated therefrom, said outer annular inlet of said second-stage reaction tube being connected to said discharge conduit of said cooling cylinder for feeding an annular stream of the liquid and gas discharged from said cooling cylinder upwardly along the internal wall of said second-stage reaction tube, said inlets terminating adjacent to the lower end of said second-stage reaction tube and the remainder of said second-stage reaction tube being open to permit concurrent upward parallel flow and contact between said streams entering said second-stage reaction tube to effect the reaction.

15. An apparatus as claimed in Claim 14 in which said trough is an inverted frusto-conical collecting receptacle at the upper end of said cooling cylinder said conduits from said first-stage reaction tubes all opening downwardly into said collecting receptacle and the inlet of said cooling cylinder being located at the lower central portion of said collecting receptacle.

16. An apparatus as claimed in Claim 14 including three concentric cylinders. the innermost one of said cylinders defining said cooling cylinder. the space between the innermost cylinder and the intermediate cylinder defining a first zone for containing a coolant and means for supplying coolant to and removing coolant from said first zone. the space between said intermediate cylinder and the outer cylinder defining a second zone for containing a coolant and means for supplying coolant to and removing coolant from said second zone, said first-stage reaction tubes being positioned in said second zone spaced from the intermediate and outer cylinder and in circumferentially spaced relation to each other, and closure plate means closing the upper and lower ends of said first and second zones.

17. An apparatus as claimed in Claim 14 wherein said conduits from the first-stage reaction tubes are reverselv curved conduits that extend radiallv inwardlv and then downwardly to communicate with said trough.

18. An apparatus as claimed in Claim 14 including means defining an enclosed space located below the lower ends of said first-stage reaction tubes, vertical nozzles extending from said enclosed space into the central portions of said first-stage reaction tubes at the lower ends thereof and defining said central inlet means, and means for supplying a current of a mixture of sulfur trioxide gas and inert gas into said enclosed space.

19. An apparatus as claimed in Claim 14 wherein said discharge conduit from said cooling cylinder is a reverselv curved conduit that extends radially outwardlv and then upwardly to communicate with the lower end of said second-stage reaction tube, said inlet means comprising concentric inner and outer pipes penetrating through said discharge conduit upwardly into the central portion of said second-stage reaction tube at the lower end thereof.