US2933451A - Process for producing a detergent mixture - Google Patents

Description

United States Patent DETERGENT i is n nt e a s o h m ni tast ra fm ted y th i detergents. ntai in lky' ary ut oaa es sett e: with c d rv u fa e alt sacti ete gent components. It deals with a new'and especially ad;-

n s o p e o p duc n fm xe de er ents i thiskind and pro'videsnovel detergent compositions hav: ing improved properties. i i

Mixturesv of alkyl aryl sulfonate detergents with alkyl sulfates have been previously proposed as useful for SP6:

cial purposes. Thus Lewis patent, U.S. 2,631,939, claims the. use of monoalkylbenzene sulfonateshaving about 12' to carbon atoms in the alkyl group with alkyl sulfates of 8 to 12 carbon atoms per molecule in amounts of l to of their combined weight as non-caking, detergent compositions. Such mixtures have, hitherfi? een pre pared by separately synthesizing thetwo types of deter-- gents and thereafter. blending them with or Without added builders.

Alkyl aryl sulfonate detergents and secondary alkyl sul fate detergents haveboth been, manufactured on a large scale for along time. The alkyl aryl-sulfo'nates are customarily made by sulfonating thecorresponding alkylated aromatic hydrocarbon, for example, alkylation products of benzene, toluene, naphthalene, or the like, with olefins using alkyiation catalysts such as sulfuric acid, hydrogen fluoride, etc. The o'lefins used in commercial practice are mixtures with varying numbers offcarbon atoms, those averaging from about 12 to about 15 carbon atoms per molecule havingbeen frequently recommended as most I 2,933,451 Patented Apr. 19,1'96Q When the alkyl aryl hydrocarbons are produced by alkylating with pure olefins or other pure alkylating agents it is not difiicult to obtain alkylates of the desired purity in high yields. But this is not the case when the alkylation is carried out with impure olefinic fractions containing olefins with different numbers of carbon atoms which are the more advantageous .alkylating agents because of theirlower cost and greater availability. In order to obtain alkyl aryl'hydrocarbons having'the desired sulfonatability from such alkylates it is necessary to remove impurities from the alkylates prior to sulfonation. This is commonly accomplished by careful fractionation of the crude alkylate. "However, since the unsulfonatable impurities boil in the same range as the lower alkylates very sharp fractionation is required. That is the cut point must beso chosen that a considerable portion of the lower alkylates are distilled over with the impurities being removed. Since these lower alkylates form v'aluable alltyl aryl sulfona tes, considerable loss inpotenti al yield'of detergent sulfonate isunavoidable inthisrnethod of operation.

When it is attempted to avoid this loss in yield of desirable sulfonates by postponing the removal of the, ur'1 sulfonatable material until after the sulfonation step, great difficulties are encountered. 'Thehigher alkyl aryl sulfonates present in the usual alkyl aryl sulfonation mix;- tures are poorly soluble in water so that pastes areformed irrthe process. These can be purified only by usingegt tremely high temperatures and/or dilutions which are undesirable. Besides adding to the cost of operation the high temperatures tend to cause discoloration of the final detergent product while high dilution involves increased expense due to the subsequent reconcentrat'ion which it foregoing disadvantages in the production of alkyl aryl sulfonate detergents. More particularly it is an object desirable. jOlefins whichare suitable for the alkylation can be obtained, for example by vapor (phase cracking of paraffin wax or of refined heavy catalytically cracked cycle oil or ...the like; or more usually by polymerizing lower olefins such, for ,e xamplejjas propyIenethetetramer fraction of which has beenfrequently used.' An excess tion and after'completion of the reaction the. excess is distilled oif from the crude alkylate. The crude'alkylate of the aromatic hydrocarbon is'usually used in the alkylatilled alkylate'are described, for example, in U.S. Patents 2,567,854 and 2,676,185, after which the alkyl aryl monosulfonic acids obtained'are. neutralized, for examplqwith I sodium hydroxide or sodium carbonate or other base to form the desired alkyl aryl sulfonate detergent.

It has been foundthat in order to obtain alkyl aryl sulfonates having the surface active properties, particularly the det er'g'encyv and sudsingpower, necessary for commercial use as a detergent, the alkyl aryl hydrocarbon must rneet rigidrequirements as to purity. Thus it is essential in present practiceto use alkyl'ates having. a. sulfonatability of atl'east 96% and more advantageously about 98% if-an allr'yl aryl sulfonate having satisfactory quality is to be obtained. That is, to say the alkyl aryl 1 hydrocarbon. chosen. must be one, which contains notmore than 4%, and morepreferablyriot more'than about 2% byweight of impuritieswhich arenot sulfonated in the process. The. sulfonatability can be determined readily, for instance, by testing a sarripleuinder theforegoing, sul fonation conditions. 3

' the poorly 'soluble'alkyl aryl sulfonates when treated makes necessary and even so usually permits only partial of the invention to provide a process for producing mixtures of alkyl aryl sulfonate detergents and alkyl sulfate detergents more economically than. is possible by the above-described prior method. A special object is the provision of a process whereby high yields of high quality alk ylfaryl sulfonate detergent can be. obtained econo'mically from alkylates having relatively low sulfonatability. Another object is the production of alkylaryl sulfonate and alkyl sulfate I'detergent mixtures having especially advantageous properties. Other objects and advantages of the. present invention Willbe apparent from the specification read in conjunction with the. appended claims.

According to the invention alkyl aryl sulfonate detergents are produced by sulfonating. alkylation products of aromatic hydrocarbons having a sulfonatability less than that which gives sulfonates of satisfactory surface active properties by the prior-method, conversion of the products to alkyl aryl sulfonic acid salts and extraction .alkyl aryl sulfonate results in a product which gives clear solutions in water and can be extracted success fully without resort to the. undesirable high temperatures and/or dilutions which are required for extractionof alon Because the process of the invention in this modifica- .tion enables the operator to use alkylates having asulj fonatability which is belowfthe minimum of 96% which has hitherto been considered necessary for the production of alkyl aryl sulfonates having desirable detergent properties and more advantageously considerably below such minimum, close fractionation of the alkylates is not essential. As a result of-the yield of useful alkyl aryl sulfonate detergent product is considerably increased without any adverse effect on the final quality of the product. Thus through the use of alkyl sulfate detergent in the extraction step it becomes feasible to use wider boiling fractions of alkylated aromatic hydrocarbons in the sulfonation step and to increase the yield of high quality alkyl aryl sulfonate detergent. Alkyl benzene fractions having a sulfonatability not greater than about 90%, for example, are useful in the process.

. The alkyl sulfate detergent which is used in the extraction step can be made in any of the usual ways. Suitable methods are described, for example, in US. Patents 2,139,393; 2,152,292; 2,172,228 and 2,618,649. The preferred alkyl sulfate detergents are water soluble salts, particularly the alkali metal, especially the sodium and/or potassium, or ammonium or amine salts of secondary alkyl sulfates having about 8 to about 18 carbon atoms per molecule. These alkyl sulfate detergents are advantageously produced by sulfating individual olefins or mixtures thereof having 8 to 18 carbon atoms by reaction with concentrated sulfuric acid, preferably of at least 85% concentration, more preferably 95% or higher concentration, at a temperature below about 100 C. and-preferably of the order of about 10 to about 50. C. and neutralizing the resulting alkyl acid sulfate or mixture of such sulfates witha suitable base, for instance a hydroxide or carbonate such as sodium hydroxide or carbonate to form the desired water soluble salt which can then be recovered and purified in known ways. 1

- It-is an advantage of the present process in one of its preferred modifications, that the production of the secondary alkyl sulfate detergent can be combined with the manufacture of the alkyl aryl sulfonate detergent so as to substantially simplify the process and reduce the overall cost of the mixed alkyl aryl sulfonate-alkyl sulfate detergent product. Thus, the neutralization of the olefin sulfation product is preferably combined with the neutralization of the alkyl aryl monosulfonic acids obtained in the sulfonationstep of the process and the mixed detergent salts thus obtained are desalted and extracted with a solvent to remove unconverted organic material especially hydrocarbon components remaining in the mixture.. 7 I,

j Most advantageously the sulfation of the chosen olefin or olefin mixture is carried out with the reaction mixture obtained in the alkyl aryl hydrocarbon sulfonation step of the process. In this way the excess "sulfonation agent which is necessary for satisfactory sulfonation of alkyl aryl hydrocarbons is used in sulfating the olefin or olefins. The sulfonation in this case is preferably carried out so that the concentration of sulfuric acid remaining on completion of the sulfonation is sufficient for the desired olefin sulfation. In order to obtain the highest yields it has been found to be advisable to employ oleum as the alkyl aryl hydrocarbon sulfonation agent, for example, oleum containing about 15% to about 30% free S Most preferably oleum is used in an amount to provide a mole ratio of $0 to alkyl arylhygdrocarbon of about to about 7, preferably about 4 to 6, to 1. Temperatures in the range' of about to about 60 C. are desirable under these conditions. However, other sulfonation conditions which give sulfonation mixtures containing sulfuric acid of at least 85% and more preferably about 95% to about 102% concentration calculated on a hydrocarbon free basis can also be used. Thus an excess of oleum of higher or lower concentration or of sulfur trioxide or of sulfuric acid of high concentration can be used at temperatures in the range of about 10 to about 100 C. By appropriate correlation with the reaction time using the stronger sulfonating agents at the lower temperatures and for shorter times good sulfonation can also be obtained.

The olefin or mixture of olefins of 8 to about 18 carbon atoms to be sulfated is added to the sulfonation with or Without additional sulfuric acid in proportions such as to provide a mole ratio of sulfuric acid to such olefin of about 0.9:1 to about 2:1, more preferably about 1:1 to about 1.6:1. The mixture is advantageously reacted at about 10 to about 30 C. using a reaction time of the order of about 2 to 30 minutes although it will be recognized that the invention is not limited to the use of these conditions.

Surprisingly, it has been found that the yield of alkyl sulfate can be increased in this process by carrying out the 'sulfa'tion of'the olefins by means of the alkyl aryl hydrocarbon sulfonation mixture in the presence of an added diluent. Paraffins' or mixtures of parafi-lns having 4 to 7 carbon atoms per molecule, such, for example, as normal butane, aromatic-free gasoline fractions, and the like, are particularly'suitable diluents for this purpose. As a rule amounts of diluent between about one-half and five volumes per volume of olefin to be sulfated are suitable.

On completion of the sulfation step of the process, the mixture of alkyl aryl monosulfonic acid and secondary alkyl acid sulfate which is obtained is neutralized, preferably with an aqueous solution of a base of the type previously indicated, and the resulting solution of mixed alkyl aryl sulfonate-alkyl sulfate salt detergents is extracted as previously indicated to remove unsulfonated organic mate- 'rial'comp'rising hydrocarbons, including saturated hydrocarbons, polymers, and unreacted alkylate and olefins, and like impurities which are detrimental to the surface-active properties of the product. Before extraction, however, it is usually advantageous to subject the mixture to a saponification treatment to convert any dialkyl sulfates present to monoalkyl sulfates. This can be accomplished by heating the neutralized mixture containing excess base, advantageously at about to about C. It is also generally preferable to treat the mixture of alkyl aryl sulfonate and secondary alkyl sulfate salt detergents to remove, at least in part, the inoganic sulfate, for example sodium sulfate, formed in the neutralizing step of the process from the unreacted sulfuric acid present. Such desalting can be carried out in any suitable manner. One such suitable method is by addition of an alcohol, for example, isopropyl alcohol, to precipitate out'the inorganic sulfatebefor'e carrying out the extraction.

vvFor the extraction of the unconverted 'organic material from the mixture of alkyl aryl sulfonate and secondary alkyl sulfate detergents in accordance with the invention, a solvent for this material which solvent is substantially insoluble in the aqueous detergent mixture is used. Hydrocarbon solvents are especially advantageous for this extraction. Suitable hydrocarbons include pure or substantially pure hydrocarbons such, for example, as benzene, toluene, pentane, hexane, diisobutylene, etc., as well as hydrocarbon mixtures such as gasoline and the like. It is preferable to choose hydrocarbons which may be readily separated by distillation from the extracts obtained in the purification step and to facilitate this they should most preferably have a boiling point or boiling range lowerthan that of the lowest boiling impurity which it is desired to remove. They should, preferably, not have too 'low a boiling point, however, as difiiculties in recovery may be thereby incurred. The hydrocarbons preferably used in the process generally boil below about 160 C. and most preferably between about 70 C. and about C., although lower or higher boiling hydrocarbons may in some cases be suitable depending upon the'characterof the impurities involved; thus even normally gaseous hydrocarbons may be used when the process is carried out under suitable superatmospheric pressure. It is of 'coursefeasible to use other types of solvents such, for

instance, as ethers. orthe. like, but these. are. generally I more expensive and offer no advantage over the preferred hydrocarbon solvents.

The: extraction can be carried out in anyof the conventional ways useful in liquid-liquid extraction. The solubilizing effect which thealkyl aryl sulfonate and secondary alkyl sulfate salt detergents have oneach other avoidsthe need for undesirably high temperaturesand/or dilution with water so that the extraction can advantageously be carried out at temperatures below 50 C. and Preferably at ordinary room temperature directly with the product from the desalting step. I

A special feature of the invention is the provision of a particularly advantageous. modification of 1' the process whereby more eflicient use can be made of olefinic mixtures made up of olefins of 8 or 9 through 18. carbon atomsper molecule. Olefinic fractions. of this kind can be produced on a large scaleby. cracking hydrocarbons.

. Vaporphase cracking. of paraflin wax, for example, has

been-used as a source of olefins of 8'to l8 carboniatoms in. producing secondary. alkyl sulfate salt detergents. Co.-

pending application Serial No. 541,826,now Patent No.

2,871,254, describes the preparation of olefinic fractions ofv 8 to 18 carbon atoms which are especially suitable for the preparation of sulfated and sulfonated detergents ac-f wetting; properties .had improved by over-100%, viz. from In order to obtain products having these desirable properties it is not necessary that the olefinic fractions be composed exclusively of olefins having the indicated ranges of carbon atoms, since small amounts, not more than about 5% of olefins with more or fewer carbon atoms can be present. Thus the C or C9 to C or C fraction may contain small amounts of C or even C olefins and C olefins while the C to C fraction may* contain small amounts totaling less than 5% of C C and C olefins including even traces of C olefins. -.A1s o the proportions of C or C to C i alkyl aryl sulfonate 'to C 5 to C alkylsulfate water soluble salt in the product mixture can be varied although for the best detergent properties it has been found desirable to control the pro: portions so that the weight ratio of these detergents in the final product isv approximately 65:35.

At a sacrifice in yield and economy the new detergent mixtures of C or C to C1235, alkyl aryl sulfonates,- particularly alkyl benzenesodium sulfonates with C 3 1 to C secondary alkyl sulfate salts, particularly the predominantly straightchain 2-alkyl sodium sulfonates, can

be produced by other methods and these improved detergents especially when containing these components in the weight ratios of about 70:30 to 60:40 which give a can be sulfonation products of alkylates obtained for ex- According to the present invention more advantageous; use is made of olefinic; mixtures which consist entirely or almost entirely of "olefins having 8 or 9 to 18 carbon atoms per molecule, by splitting the mixture, for example by fractionation, into a lower boiling fraction of olefins of 8 or 9 to 12:1. carbon atoms per molecule and ahigher boiling fraction of olefins of 13:1 to 18 carbo'n atomsper moleculeand convertingthe lower boiling fraction into alkyl aryl sulfonates andthelhigher boiling fraction into secondary alkyl sulfate salt detergents. By carrying out the preparation of these alkyl aryl sulfonate and secondary alkyl, sulfate salt detergents by the; process of the present invention, the starting C or C to C can be used in its entirety and loss of'yield. due to segregation of alkylate of. high 'sulfonatability is avoided by taking advantage of the mutualsolubilizing effect which the alkyl aryl sulfonate and secondary alkyl sulfate salts haveon each other in the extraction step of the process.

' A further advantage of thismodification of the processes of the invention is'that detergent mixtures can be produced having considerably betterdetergent, foaming and wetting properties than alkyl-'aryl sulfonates or alkyl sulfate detergents prepared fromthe entire C or C to C1 olefin mixture. When, for example, a C to C sodium alkylsulfate mixture was compared with a. mixture prepared according to the invention, it was found that in the latter case the yield of active detergent material was increased from approximately 90% by Weight to 134% by weight, calculatedZon the initial olefinic feed, while the foam number had increased from 20 to 2 7. The clear point (which is a measure of stability of the solutions against turbidity at low temperatures) of the mixture prepared according to the; invention was also found to have improved. In 7% and 21%"concentrationsin water the clear point was 3 C. and 4? C. respectively, whilethe corresponding values for; the orC to C alkyl sul' V atamixturew re 1,2,..'C ..and.. Q. 3 12ectite y.-v I119 desirable combination of surface-active properties are a,

feature of the invention regardless of their method of preparation. i

It will be understood, moreover, that the process of the invention in its various modifications is not limited to the preparation of these especially valuable compositions but can be advantageously used in the manufacture of many, other mixtures of alkyl aryl sulfonates and secondary'alkyl sulfate salt detergents; Thus the sulfonates ample by reacting benzene, toluene, or othermonocyclic aromatic hydrocarbons or mixtures thereof such, for instance, as aromatic extracts of mineral oils and thelike, or naphthalene or methylnaphthalene, etc.,.with olefins or olefinic mixtures containing olefins of 8 to 20 or more carbon atoms per molecule; Detergent mixtures of such alkyl aryl sulfonates with water-soluble secondary alkyl sulfate salts which can be individual compounds or mix tures whereinithe alkyl groups contain 8 to 20 or more carbon atoms are useful'products of the new process. Especially useful products areffor example, obtained.

when alkylbenzene sulfonates made. via alkylation with olefins of 8 or 9 to 12 to 13 carbon atoms are extracted in admixture with sodium alkyl sulfates from mixtures of olefins of 8 or 9 to 18 carbon atoms. Proportions of secondary alkyl sulfate salt detergents inthe mixture can be as high as by weightof the totalalkyl aryl sulfonate and secondary alkyl sulfate salt detergent content and preferably is at least 30%. Especially advantageous products are. obtained by using. in the process mixtures of alkyl aryl sulfonates and secondary alkyl sulfate salts in ratios between about 60:40 and 20:80 when employing special combinations of these sulfonates and sulfate salts. These are mixtures of alkylaryl sulfonates, preferably monoalkyl, benzene monosulfonates,

having 8 and/or 9' carbon atoms-in the alkyl groups,

preferably together With one or more alkyl aryl sulfonates, preferably monoalkylbenzene monosulfonates having 10, 11, 12 or 13 carbon atoms in, thealkyl groups and virtually free from alkyl' aryl sulfonates having less than 8 or more than 13 carbon atoms in the alkylgroups, withmixtures wholly or almost entirely consisting of secondary alkyl sulfates having 8 or. 9 to.18 carbon atoms per molecule. 'fsuch products can be readily obtained for example by adding a C C or C C fraction of olefins incontrolled proportions to the sulfonation product of a C5-C alkylbenzene, for instance, and sulfating the added olefins, neutralizing the mixture, desalting and extracting as, previously. described. v

' The mixed alkyl aryl sulfonate and secondary alkyl sulfate salt detergentsobtained by the process can be used as such in the form of aqueous solutions or can be dried and used as flakes of powders, etc. Builders such as pyro or polyphosphates, silicates, carbonates, and the like can be added, as can any of the various known foam stabilizers, washing agents, bleaching agents, etc. used with detergents of these types. Other detergents including alkyl aryl sulfonates and/or secondary alkyl sulfate salt detergents from other sources, or fatty acid soaps or non-ionic detergents or wetting agents or emulsifiers can bebiended with the product for special purposes.

The invention is further illustrated by the following examples in which suitable methods for cairyingout the new process are shown together with new compositions of the invention,it being understood that the invention is not restricted to the specific reactants, operations, conditions or compositions thus exemplified since these can be varied considerably without departing from the scope of the invention.

Example I Benzene was alkylated in a stirred reactor with a C to C fraction of olefins obtained by vapor phase cracking of solvent refined catalytically cracked heavy hydrocarbon oil. The alkylation was carried out with hydrogen fluoride as catalyst using a volume ratio of hydrocarbon to catalyst phase of 1:1. The mole ratio of benzene to olefin was 10:1. The reaction was carried out at room temperature under a pressure of 4 atmospheres absolute using a stirring rate of 220 r.p.m.

; After a residence time of .30 minutes the reaction was completed and the catalyst phase was then removed. The excess benzene was distilled oflE from the hydrocarbon mixture at atmospheric pressure, following which the remaining hydrocarbons were distilled at 40 mm.- mercury pressure to separate a small amount of light and heavy ends and obtain a C C alkylbenzene alkylate which had a sulfonatability not exceeding 90%.

This alkylate was sulfonated at 55 C. with oleum using a mole ratio of 80;; to alkylate of 3:1. On completion of the reaction a small amount of water sufficient to reduce the concentration of sulfuric acid in the mixture to 65% to 75% was added whereby a sulfuric acid phase essentially free from alkylbenzene sulfonic acids was formed and decanted from the sulfonic acid phase.

A mixture of C3-C18 secondary alkyl sulfuric acid prepared by sulfating a C r-C fraction of olefins from hydrocarbon cracking with 98% sulfuric acid was added to the C -C alkylbenzene sulfonic acids thus prepared in a weight ratio of 60:40. The mixture was then neutralized with excess sodium hydroxide and then heated to convert the dialkyl sulfates present into monoalkyl sulfates. To the saponified mixture there was added of isopropyl alcohol and the resulting mixture was stratified and inorganic salts were separated. The thus desalted mixture of sodium C -C alkylbenzene sulfonates and C C sodium secondary alkyl sulfates was extracted with gasoline which eifectively removed the unconverted organic impurities giving a detergent mixture having excellent surface-active properties.

The yield of detergent thus obtained was 15% greater, calculated on the olefins, and 18% greater, calculated on thebenzene, than that obtained in preparing the same mixture by blending corresponding amounts of the same .Cg-C13 alkylbenzene sodium sulfonates and C C secondary alkyl sodium sulfates separately prepared in the usual way.

Example II A Ca-Cm olefin mixture from the vapor phase cracking of parafiins was split by distillation into a C -C and a C -C fraction.

The C -C fraction was used to alkylate benzene in virtually the same way as described in Example I, and

an alkylate was recovered having a sulfonatability of not more than 90%. The mixture obtained after sulfonating these C -C alkylates as described in Example I. was then used for 'the sulfation of the C C fraction of the olefins.

The mixtures of benzene sulfonic acids and acid sulfates obtained in this way were neutralized, saponified, desalted and extracted with gasoline as described in Example I. The improvement in the yield obtained by the process of the invention was 15%, calculated on the olefins used, compared with that obtained by preparing the same C C alkylbenzene sulfonates and C -C secondary alkyl sodium sulfates separately in the usual way and then blending them to produce a similar mix ture. v

The mixture thus obtained was compared in a num-. ber of foaming and wetting tests with a C -C sodiumsecondary alkyl sulfate mixture from the same starting mixture of olefins having 8-18 carbon atoms in the molecule. The results are shown in the following table.

CB-Cfl Alkyl .Aryl Sulfo- Cs-GraSecnates Cir-Ora condary Secondary Alkyi Alkyl Suliates Sulfates in Ratio by Weight of 66:34

Foam Number 1 20 27 Wetting Effect (Di-a es Test) 100 219 Clear Points 1 at a Concentration 7%by weight 12 3 21% by weight 13 4 34% by weight 14 5 40% by weight 15 7 Yield calculated on olefln s ting mate rial, percent 90 134 1 The temperature in 0. at which a turbid aqueous solution of the detergent clarifies during gradual heating. A measure of the stability 01 the solution against turbidity (precipitation or gelling) on cooling.

Example III A C C olefin mixture, obtained by vapor phase cracking of refined heavy hydrocarbon oil obtained by Cg-Cn and a Cm-Cm fraction. catalytical cracking, was split by distillation into a Benezene was alkylated with the use of the C -C fraction in substantially the same way as described in Example I. The alkylate was sulfonated at 55 C. with oleum containing 23% of free S0 starting with a mole ratio of S0 to alkylate of 6.511. Towards the end of the sulfonation reaction the C -C olefin fraction was added to the mixture and thus sulfated.

After neutralization and extraction with hydrocarbon to remove unconverted material and other hydrocarbon impurities, a mixture was obtained consisting of 56 parts by weight of alkyl aryl sulfonate and 44 parts by weight of alkyl sulfate. This mixture, as regards its desired properties, was also found to be considerably superior to the usual alkyl aryl sulfonate mixtures or alkyl sulfate mixtures, as is shown in the following table.

Cs-Cn Alkyl Aryi Sulfon- C3-C1: Secetcs Cit-oil condary Secondary Alkyl Alkyl Sulfate: Sulfutes in Ratio by Weight 01' 66:44

Foam Number 20 24 Wetting Effect (Draves Test) Clear Points at 9. Concentration of 7% by weight--. 12 21% by weight. 13 7 Yield calculated on olefln starting mate rial, percent 90 124 9: Example IV;

The starting material was a C C crackedfdistillate fraction (boiling from 145 C. to 300 C.) froma, thermal vapor phase cracked product of a rafiinateob tained in the extraction of aromatics by means Ofz flll C., and of the residual oil drawnofi' asbottom product I agsssyeon in this fractionation; This C -C crackeddistillate frac-- tion which had an alkene content of approximately; 90%. by weight was distilled to separate-a C -C fraction, and;

a Ci C fraction.

The C -C fraction Wasused to. alkylatetoluene em;-

ploying sulfuric acid of 90% concentration as.the.cata=; lyst in a volume ratio about equal to the'volume of the,

hydrocarbon reactants and, a. mole ratio or" toluene to olefins of 6:1. After reaction at'Of toz5 C. for "about v 730 minutes with vigorousstirring, the mixture was. settled, and the hydrocarbon layer .decanted, neutralized,

and. distilled to remove excess toluene and light and. heavy ends and obtain .an alkylate fractionhaving a.

sulfonatability of less than 90%.

This alkylate was sulfonated with 20%, oleum-usingfa. mole ratio of free to alkylate of 3:1. and a temf0 s two runs which-were conducted at 10215 C: and about5 (3., respectively. The sulfonation yield wam 98% ineach case; The products recovered after new tralization with sodiumhydr'oxide and removal of undesirable hydrocarbon impurities as previously described had excellent surface-active properties and were obtained in substantially improvedyields compared with separate preparation of the- C -C alkylbe nzene" sodium sul fonatc and cg-C secondary alkyl sodium sulfate components.

Sulfatlon Volume Mole Ratio by Ratio, Ratio, Weight of. d s Pentane to Alkylate- Sulfation Sulfonate Mole Ratio, Concen- Cracked to Cracked Yiel to Sulfate Cracked tration: Wax: Wax percent in Final: Wax Oleflns H180 Olefin: Olefins Product I t0 H230 sulfonlc'aeid. After sulfonatlon-oleum ,of 60%' was added inorder to increase, the $80.4 concentration from 97.9% to 100.9%.

' Calculated without taking into account the dilution with I The'same result can be obtained by sulfonating with a mole perature of about 45 C. for 40 minutes. On completion of the sulfona tion-at which. time the concentration;

of sulfuric acid in the reaction mixture was about 98%. on an organic-free basis, the (In-C fraction of olefins was added to the mixturelwith continuedstirring and cooling to about 0 to 5" C. About 0.6 mole of the olefinic mixture was "added per mole of free sulfuric acid in the sulfonation product. After about 10; minutes reaction'time, themix-ture was diluted with sufiicient water to cause separation of a layer containing sulfuric acid of about 70% concentration which was drawn off and I the mixture of c -C g-alkyl-toluene sulfonic acids and C -C secondary alkyl sulfuric acidsremaining was neutralized with excess sodium hydroxide and the mixture heated to saponify the dialkyl sulfates present to alkyl sulfate sodium salts. The saponified mixture was then diluted" with of'isopropyl alcohol andliquid phase desalting was carried out, following which the mixturewas extracted with gasoline and the hydrocarbon impurities substantially removed.

1 The mixed C -C alkyltoluene sodiumsulfonate-C C secondary alkyl sodium sulfate detergents obtained containing sulfonate to alkyl sulfate detergent in a weight ratio of about 65 to together, with about 10% by weight of sodium sulfate, have somewhat lower foaming power than the corresponding product made by alkylating benzene but are good detergents. 'The yield based on olefins used is about 10 mole percent higher than is obtained when the active components are prepared separately in theusual way.

Example V q The following table gives the data relating to a number of tests for preparing mixtures of alkyl benzenes and sulfonates and. secondary alkyl sulfates. The starting mixture of alkyl benzenes contained compounds with 10- i S0 to alkylate of 5:1 and a reaction time of 30 min- Q utes at 55 C. The sulfation was then'eifected by adding the C -C fraction of olefins to the sulfonation mixture with or without pentane-as diluent as shown in the table and stirring for 10 minutes at 0 0., except in the ratio of allrylate: S0 of 1 6.66.

We claim as our invention:

1. A process for producing a mixture of alkylaryli. sulfonate' and secondary alkyl sulfate salt detergents which comprises sulfonating an alkyl aryl hydrocarbon; fraction having alkyl groups of at least 8, and not more than 20, carbon atoms, and asulfonatability of less than 96% due to impuritieswhich are not converted to desirable alkylaryl' sulfonic acid during the sulfonation and reduce-the surface'activity of the alkyl aryl sulfonate cle-- tergent obtained onneutralization of the sulfonationproduct, extracting the aqueous neutralized sulfonation product in thepresence of at least 10%, based on the. weight of said alkyl aryl sulfonate, of secondary alkyl sulfate salt detergent, containing 8 to 18 carbon atoms per molecule, with 'a hydrocarbon solvent for said impurities, said solvent boiling within the range of from about 70 toabout 160 C., and being substantially insoluble in the aqueous solution of said secondary alkyl sulfate salt detergent' -containing neutralized sulfonation product, whereby removal of impurities is eifected and a detergent mixture havingimproved surface-active properties is obtained.

2. A process in accordance with claim 1 wherein an alkyl benzene fraction having alkyl groups of at least 8 carbon atoms and not more than 18 carbon atoms and a sulfonatability not greater than about is sulfonated and the extraction is carried out with hydrocarbon boiling between about 70 C. and about C.

3. A process for producing a mixture of alkyl aryl sulfonate of the benzene series and secondary alkyl sulfate salt detergents wherein said alkyl groups contain not less than 8 nor more than about 18 carbon atoms, which comprises sulfonating an alkylation product of a hydrocarbon of the benzene series corresponding to said sulfonate and having a sulfonatability not greater than about 90%, adding to the resulting alkyl aryl monosulfonic acid product secondary alkyl sulfuric acid correspond ing to said alkyl sulfate salt in an amount between about 30% and about 80% of the total weight of said monosulfonic acid and alkyl sulfuric acid, neutralizing and desalting the mixture and extracting unreacted hydrocaralkylbenzene fraction having a sulfonatability not greaterthan about 90% wherein the alkyl groups contain not less than 8 normore than about 18 carbon atoms with an excess of sulfonating agent,jadding'to the alkylbenzene monosulfonic acid-containing reaction mixture at least one olefin of 8 to 18 carbon atoms per molecule, maintaining the mixture under sulfating conditions until substantial reaction of said olefin has taken place, neutralizing the resulting mixture of sulfonic acidand secondary alkyl sulfuric acid with a basic sodium compound, separating inorganicsalt formed in the neutral-Y ization step from the sodium sulfonate and'secondary alkyl sulfate salts produced and extracting the mixture with agasoline fraction boiling in the range of about 70 C. to' about 140 C. to remove hydrocarbon impurities therefrom.

5.. A process in accordance with claim 4, wherein the sulfonation is carried out with an amount of oleum such that the sulfonation mixture contains sulfuric acid of at least 95% concentration on an organic free'basis on completion of the sulfonation step.

6. A process in accordance with claim 5 wherein the sulfation is carried out in the presence of an added paraffin diluent having 4 to 7 carbonatoms per molecule. 7.-A process in'accordance with claim 5 wherein the sulfation is carried out with a mole excess of sulfuricacid based on said olefin.

8. A process for producing a detergent mixture, comprising-alkylating benzene with a fraction of olefins from hydrocarbon cracking containing olefins of 8 to 9 carbon atoms per molecule and essentially free from olefinsof more than 13 carbon atoms, sulfonating-the resultingalkylate having a sulfonatability not greater than about 90% to produce predominantly monoalkylbenzene monosulfonic acids, converting said sulfonic acids to water soluble monoalkylbenzene sulfonate salts and extracting said sulfonate salts with a liquid hydrocarbon boiling between about 70 C. and about 160 C. in the presence of C to C secondary alkyl sulfate salts in an amount equal to 40% to about 80% of the total weight of said monoalkylbenzene sulfonate salts and said secondary alkyl sul-' fate salts in the mixture. p

9. A process for producing a mixture of water soluble alkylbenzene sulfonate detergent salt and secondary alkyl sulfate salt detergent which comprises fractionating a mixture of olefinic products of hydrocarbon cracking containing olefins of 8 to 9 through 18 carbon atoms per molecule, to separate a lower boiling fraction con-" extraction beingcarried out with a hydrocarbon solvent for hydrocarbon impurities present in the mixture which r'educe the surface-active properties thereof whereby sub-. stantialremoval of said impurities is efiected said hydrocarbon solvent boiling between about 70 C. and about 140C.

10. A process in accordance with claim 9 wherein the neutralization of the secondary alkyl sulfuric acids is car-. ried out by adding a base to a mixture of said alkylbenzene sulfonic acids and said alkyl sulfuric acids in weight ratios of 70:30 to 60:40.

, 11. A process in accordance with claim 10 wherein;

the higher boiling fraction of olefins is added to said sulfonation mixture and the sulfation of the olefins effected therein. I 1

References Cited in the file of this patent UNITED STATES PATENTS 2,529,538. Henry et al. Nov. 14, 1950" 2,529,539 Brod et al. Nov. 14, 1950 12,617,772 Keenan Nov. 11,1952 2,631,980 Lewis Mar. 17, 1953 FOREIGN PATENTS 635,303 Great Britain Apr. 5, 1950 704,687 Great Britain Feb. 24, 1954 Great Britain Apr. 6, 1955

Claims (1)

1. A PROCESS FOR PRODUCING A MIXTURE OF ALKYL ARYL SULFONATE AND SECONDARY ALKYL SULFATE SALT DETERGENTS WHICH COMPRISES SULFONATING AN ALKYL ARYL HYDROCARBON FRACTION HAVING ALKYL GROUPS OF AT LEAST 8, AND NOT MORE THAN 20, CARBON ATOMS, AND A SULFONATABILITY OF LESS THAN 96% DUE TO IMPURITIES WHICH ARE NOT CONVERTED TO DESIRABLE ALKYL ARYL SULFONIC ACID DURING THE SULFONATION AND REDUCE THE SURFACE ACTIVITY OF THE ALKYL ARYL SULFONATE DETERGENT OBTAINED ON NEUTRALIZATION OF THE SULFONATION PRODUCT, EXTRACTING THE AQUEOUS NEUTRALIZED SULFONATION PRODUCT IN THE PRESENCE OF AT LEAST 10%, BASED ON THE WEIGHT OF SAID ALKYL ARYL SULFONATE, OF SECONDARY ALKYL SULFATE SALT DETERGENT, CONTAINING 8 TO 18 CARBON ATOMS PER MOLECULE, WITH A HYDROCARBON SOLVENT FOR SAID IMPURITIES, SAID SOLVENT BOILING WITHIN THE RANGE OF FROM ABOUT 70* TO ABOUT 160*C., AND BEING SUBSTANTIALLY INSOLUBLE IN THE AQUEOUS SOLUTION OF SAID SECONDARY ALKYL SULFATE SALT DETERGENT-CONTAINING NEUTRALIZED SULFONATION PRODUCT, WHEREBY REMOVAL OF IMPURITIES IS EFFECTED AND A DETERGENT MIXTURE HAVING IMPROVED SURFACE-ACTIVE PROPERTIES IS OBTAINED.