SURFACTANT COMPOSITIONS, PREPARATION AND STABILIZATION OF COAL IN OIL MIXTURES

Abstract: Highly concentrated homogeneous liquid surfactant com­ positions are provided which are particularly advantageous for stabilizing mixtures of pulverized coal in fuel oil useful in con­ ventional fuel oil burning equipment. The surfactant composi­ tions can be prepared by neutralizing an admixture of a nonion­ ic alkylaryl polyoxyalkylene ether and an alkylarylsulfonic acid with C₁₋₃ alkanolamine.

Description: SURFACTANT COMPOSITIONS, PREPARATION AND STABILIZATION'OF COAL IN OIL MIXTURES BACKGROUND OF THE INVENTION This invention relates to very highly concentrated liquid surfactant compositions and a method of producing such compositions which contain a nonionic component, an alkanolamine-containing anionic component and not more than about 10% by weight solvent. The highly concentrated liquid surfactant compositions are useful where concentrated mixtures of nonionic/anionic components are desired. They are particularly useful in the method of stabilizing coal in fuel oil mixtures of this invention. Surfactant mixtures are well knownin the art. Typically such compositions are useful in detergent 3ppli- cations and contain surfactants which are anionic,nonionic, mixed anionic-nonionic or zwitterionic in nature. These compositions contain significant amounts of solvent, usually water and/or alcohol and frequently contain a hydrotrope or solubilizing agent. The solvents are required to obtain homogeneous, fluid compositions as well as to facilitate formulation of such mixtures. This requirement limits the active content of known surfactant mixtures and thus their volume usage/performance ratio. U.S. Pat. No. 3,867,316 describes a process for manufacturing flowable pasty detergents capable of being pumped containing 60 to 70 weight percent of active substance of organic sulfuric or sulfonic acids neutralized with alkalies. U.S. Pat. No. 3,928,249 describes liquid, aqueous, detergent compositions containing from 2 to 15% by weight solubilizing agents. Also, U.S. Pat. No. 4,235,758 describes clear, liquid detergent compositions containing 30-55% by weight of an active detergent mixture. Surfactants useful in the preparation of coal in fuel oil mixtures are described in U.S. Pat. Nos. 4,130,401 and 4,162,143. In the preparation of such coal in fuel oil mixtures, it is highly desirable to use effective surfactant compositons which are concentrated, homogeneous, fluid, stable to freeze/thaw conditions and easily dispensable. Such concentrated surfactant compositions facilitate the preparation of coal in fuel oil mixtures in the extremely large volumes required as an alternative fuel useful in fuel oil burning equipment. Stable, concentrated su-rfactant compositions, for example, can be readily metered into an admixture of coal and fuel oil with agitation using batch processing techniques or continuous processing techniques employing in-line mixers. Accordingly, an advantage of the present invention is providing liquid compositions of anionic and nonionic surfactants which have very high active contents and do not require solubilizing agents to maintain homogeneous, fluid properties and have superior volume usage/ performance ratios. A further advantage of this invention is providing a process for preparing such compositions which is efficient, direct, and avoids the usual requirement for a substantial proportion of diluent solvent in the production of anionic/nonionic mixtures. An additional advantage of the present invention is providing such high active surfactant compositions which are chemically and physically stable and are particularly useful in the preparation of pulverized coal in fuel oil mixtures which can be used as an alternative fuel. It has been discovered that by employing certain anionic and nonionic surfactants in a preferred manufacturing process, these above described advantages are attained and very high active content surfactant compositions can be prepared which are unexpectedly superior to surfactant mixtures presently known in the art. SUMMARY OF THE INVENTION These and other advantages are attained by the liquid surfactant compositions of the present invention which consist essentially of: (A) a nonionic component of alkylphenol polyoxyalkylene ether; an an anionic component of alkanolamine salt of alkylaryl sulfonic acid; and (C) not more than about 10 weight percent solvent, wherein the weight ratio of (A) to (B) varies between about 1 to 3 to about 3 to 1. These surfactant compositions are prepared by the process of this invention which comprises admixing a nonionic alkylaryl polyoxyalkylene ether and alkylaryl sulfonic acid and adding to the admixture mono-, dior tri-C13 alkanolamine in an amount sufficient to neutralize the alkylaryl sulfonic acid. This in situ neutralization with an alkanolamine of the alkylaryl sulfonic acid in admixture with,the alkylaryl polyoxyalkylene ether is particularly advantageous in that all components are in a fluid state and thus readily dispersed and handled. The method of preparing coal in fuel oil mixtures of this invention comprises admixing about 30 to about 50 parts by weight pulverized coal, about 50 to 70 parts by weight fuel oil, not more than about 10 parts by weight of water and a sufficient amount to stabilize the coal in the oil of the above liquid surfactant compositions of this invention. DETAILED DESCRIPTION OF THE INVENTION The nonionic component of the liquid surfactant compositions are conventional nnionic surfactants of the alkylaryl polyoxyalkylene ether type. The polyalky-lene oxide condensates of alkylphenols are particularly useful. These components include products of alkylphenols having an alkyl group containing from about 8 to about 12 carbon atoms in either a straight or branched chain configuration, i.e., C8-12 alkylphenols, with about 4 to about 12 moles of alkylene oxide containing 2 or 3 carbon atoms, i.e., C2.3 alkylene oxide, preferably ethylene oxide. Especially preferred are alkylphenol polyoxyethylene ethers wherein the alkylphenol has 8-9 alkylene carbon atoms and is condensed with 4-10 moles of ethylene oxide and also where the alkylphenol has 12 carbon atoms in the alkylene chain and is condensed with 6-10 moles of ethylene oxide. Examples of nonionic components of this type which are commercially available include nonylphenol condensed with an average of 10 moles of ethylene oxide, dodecylphenol condensed with an average of 6 moles ethylene oxide, and octylphenol condensed with an average of 8 moles of ethylene oxide. Similar alkylphenols condensed with propylene oxide can be employed. The anionic component of the surfactant compositions of this invention are alkanolamine alkylaryl sulfonates which can be generated in situ in accordance with the process of this invention by the reaction of a C13 alkanolamine and an alkylaryl sulfonic acid using the nonionic component of the surfactant composition as the medium for reaction. The commercially available alkylaryl sulfonic acids derived from alkylbenzenes having average molecular weight ranges of 231-241, wherein the dominant alkyl chain length is C11; 238-248, wherein the dominant alkyl chain length is C12; 258-266, wherein the dominant alkyl chain length is C13; and 300-400, which are viscous liquid by-products of alkylbenzene manufacture, for example 335 average molecular weight wherein the toal number of carbons in the alkyl portion averages about 1S; which are hereinafter referred to as alkylaryl sulfonic acids wherein the average carbon number of the alkyl chains varies from about 10 to 15, i.e., C10-15 alkylbenzenes, are preferred. Especially preferred are the alkylbenezene sulfonic acids with an average alkyl chain length, either straight or branched chain, of about C1113 An example of this type of sulfonic acid is dodecylbenzene sulfonic acid. Preferred alkanolamines are monoethanolamine, diethanolamine, triethanolamine and mixtures thereof. Other alkanolamines having 1 'to 3 carbon atoms in the alkanol portion, i.e., mono-, di-, and tr'i'C1¯3 alkanolamines can be used. The weight ratio of the nonionic component (A) to the anionic component (B) in the surfactant composition of this invention can vary over a broad range to tailor its surfactant properties in view of the desired use. Preferably, the weight ratio of (A) to (B) varies between about 1 to 3 to about 3 to 1. Particularly preferred are surfactant compositions of 40 to 60% by weight of the anionic component (B) based on the total weight of (A) plus (B). Although the surfactant compositions of the instant invention need only contain the above-described components to be easily prepared and liquid at 250C, highly preferred compositions contain additionally a small amount of solvent, not more than about 10% by weight, to enhance their physical properties at low temperatures. Generally, such solvents comprise from about 5 to about 10X by weight of the total compositions. The physical properties at low temperature are improved by selected solvents which lower the clear points and which also improve the fluidity at lower temperatures which may be encountered during shipping or storing of the surfactant composition in the marketplace. Preferred solvents vary somewhat as the structure and relative weight ratios of the components (A) and (B) of the surfactant compositions are varied. In general, lower molecular weight alkanolamine salts and anionic weight percentages of about 25% require less solvent and a wider range of solvents can be employed. Preferred solvents for mono- and diethanolamine sulfonates used at about 25% by weight are lower molecular weight alcohols, i.e., C13 alcohols, especially methanol, ethanol, and isopropanol, formamide and mixtures thereof. Five percent by weight of these preferred solvents is typically sufficient to provide lower clear points and fluidity to the compositions. Higher molecular weight alkanolamine sulfonates and compositions wherein the amount of the anionic component is greater than about 45% by weight benefit from a somewhat higher level of solvent. Especially preferred solvents for these compositions are methanol, ethanol, isopropanol, formamide and mixtures thereof at 5-10% by weight of the total compositions. Although water as a solvent does not enhance the properties of the surfactant compositions as well as the mentioned preferred solvents, water is preferred for compositions wherein the anionic component is an alkanolamine salt of alkylaryl sulfonic acid derived from the above described alkylbenzene by-product having an average molecular weight of 335. It will be recognized that other solvents may be employed in the surfactant compositions. In general, however, such common solvents as ethylene glycol, acetone, napthas, kerosene, higher -alcohols, and aromatic solvents such as toluene and xylene, do not enhance the clear point or fluidity at lower temperatures as compared to preferred solvents. The generally practiced and accepted method for preparing liquid anionic surfactants as well as liquid surfactant blends with high active content involves sequential addition of the various active components to a diluting solvent. In such liquid formulation the solvent is usually water and/or alcohol. Although the use of solvents facilitates mixing of these formulations, the relatively large amount of solvent required inherently limits the active content of the resultant finished composition. In additon, the amount and ratio of solvents often must be carefully controlled to avoid gel formation and phase separation. The process of the present invention provides a substantial improvement over the aforementianed art for preparing high active content liquid mixtures of anionic and nonionic surfactants, while avoiding the need for diluent solvents during preparation and the problems of gel formation. In addition, it has been found that compositions prepared by the process of this invention unexpectedly exhibit excellent fluidity and physical and chemical stability. This process entails the preparation of alkanolamine sulfonates in the presence of the nonionic surfactant which serves as the reaction medium. In this manner, all of the raw materials are in liquid form and easily handled and metered. A particular advantage of this process is the avoidance of handling of concentrated alkanolamine sulfonate, which is typically waxy,,hydro- scopic and- difficult to obtain in concentrated form. According to the present process, an alkylÅaryl sulfonic acid is added to a liquid nonionic surfactant of the aforementioned type and mixed well. The materials are essentially completely miscible over the range of composition described previously. Next, the required amount of alkanolamine, based upon desired stoichiometry, is added; a rapid rate of addition can be used. The resultant mixture of nonionic surfactant and alkanolamine sulfonate is mixed well and a suitable solvent can then be added if desired. The entire procedure is convenient, rapid, easily reproducible and affords a very homogeneous, fluid surfactant composition. In the method of preparing coal in fuel oil mixtures of this invention, the pulverized coal can be prepared by techniques known to those skilled in the art. A standard coal pulverizing unit cominutes about 80 percent of the coal to less than 200 mesh U.S. Standard Sieve particles (less than about 74 microns) and the pulverized coal produced in such standard units provides satisfactory results in the method of the present invention. However, as will occur to those skilled in the art, even finer coal particles will produce better dispersions in the fuel oil, but the cost of producing such finer coal frequently offsets the benefits of better dispersions. As is known to those skilled in the art, the composition of coal can vary within rather wide limits, depending upon the seam from which it is mined, the mining technique used and other conditions. This variation in composition affects the performance of the surfactant compositions employed to stabilize the coal in fuel oil mixture and usually is adjusted for by selection of the proper nonionic and anionic component, the weight ratio thereof, the concentration of the surfactant composition based on the weight of the coal in fuel oil mixture as well as the concentration of the added water and the coal in the coal in fuel oil mixture. The optimum coal in fuel oil mixtures can be readily determined for a particular coal or oil by those skilled in the art by simply admixing the pulverized coal with the fuel oil, added water and the particular surfactant composition and determining the settling rate of the pulverized coal, using the procedure of Example XIII. The fuel oil can also vary within wide limits, depending on the source do the oil, the refinery methods, and the like. Residual fuel oil, which is the product from refineries after lighter fractions used to make gasoline and other petroleum products have been removed, has been generally used as a fuel for firing boilers and other heat generating applications. Typically, fuel oil has a specific gravity at 150C. of about 0.9, a boiling point of about 3550C, and a flash point of about 950C. Of particular interest are fuel oils designated in the art as grades 4, 5 and 6 which are most often used in the stoking of boilers and the like. Grade number 6, such as, Bunker C fuel oil is particularly advantageous in view of its lower cost and commerical availability. The variation in the characteristics of the fuel oil does not affect the stability of the coal in fuel oil mixtures to the extent that coal affects the mixture. Preferably, low:levels of water can be admixed with the pulverized coal and fuel oil according to the present invention. Such low levels of water aid in the dispersion of the pulverized coal in the fuel oil. As those skilled in the art are aware, when greater than about 10 percent water, based on the weight of the coal and the oil, is used there is a loss of fuel value. However, when less than about 1 weight percent water based on the weight of the total mixture is used, no particular advantage is seen in the addition of the water. Coal in fuel oil mixtures of this invention containing between about land about 5 weight percent added water are preferred. The optimum nonionic and anionic components and the weight ratio thereof in the liquid surfactant compositions of this invention for any particular coal and oil can be readily determined by routine experimentation in view of the instant disclosure and the results provided in the examples below. The amount of the surfactant composition required to stabilize the coal in the oil can vary with the particular coal and oil. Although less than 0.1 weight percent of the surfactant composition will show some beneficial effects, it is preferred to use at least 0.2 weight percent. For reasons of economy greater than 1 percent surfactant composition is not recommended, although such higher amounts are not detrimental. It is preferred to use 'less than 1 percent by weight, usually less than 0.5 weight percent of the surfactant composition, based on the total weight of the coal in fuel oil mixture. DESCRIPTION OF PREFERRED EMBODIMENTS This invention is further illustrated by, but not limited to, the following Examples wherein all parts and percentages are by weight unless otherwise indicated. EXAMPLE I A surfactant composition of nonionic and anionic components in the weight ratio of 1 to 1 is prepared in the following manner: An open mixing tank fitted with an agitator is charged with 2.01 kg of nonylphenol ethylene oxide condensate containing an average of 10 moles of ethylene oxide per mole of nonylphenol. With mixing, 1.37 kg of a sulfonic acid of a dodecylbenzene having an average molecular weight of 236 is added, whereupon a moderate temperature rise occurs. Next, 0.71 kg of triethanolamine is metered into the mixture at a uniform, relatively rapid rate. Final triethanolamine addition is controlled such that a 1% solution of the mixture has a pH value of 7-8. The finished mixture is a clear, homogeneous composition having an approximate viscosity of 1800 cps (1.8 Days) at 250C. Then ethanol, as solvent, is added to the mixture to comprise 7.5% by weight of the total composition which improves its fluidity by reducing the viscosity to approximately 650 cps (.65 Palms) at 250 C. The liquid surfactant composition of Example I is a homogeneous, clear, amber,liquid which is freeze/ thaw stable. This composition is physically and chemically stable showing no phase separation or gelling upon standing at room temperature for 30 days or in the accelerated aging test for 5 days at 500C and for 3 days at 0 C. At OOC, this composition remains fluid and readily pumpable. Substantially like fluidity and stability results were obtained with the replacement of the 7.5% ethanol with 7.5% (95) ethanol, 10% methanol, 10% formamide and 10% of a mixture of, equal parts of ethanol and formamide. EXAMPLE II The procedure of Example I is repeated except that 1.69 kg of the dodecylbenzene sulfonic acid is used and 0.325 kg of monoethanolamine is substituted for triethanolamine. Using 7.5% by weight of 95% ethanol provides a clear, homogeneous, liquid surfactant composition having a clear point below OOC. The composition is physically and chemically stable showing no phase separation or gelling upon standing at room temperature for 30 days or in accelerated aging test for 5 days at 500 C and for 3 days at OOC. At OOC, the composition remains fluid and readily pumpable. EXAMPLE III The procedure of Example I is repeated except that 1.51 kg of dodecylbenzene sulfonic acid is used and 0.50 kg of diethanolamine is substituted for triethanolamine. Using 7.5% by weight of 95% ethanol provides a clear, homogeneous, liquid surfactant composition which is physically and chemically stable showing no phase separation or gelling upon standing at room temperature for 30 days or in the accelerated aging tests described in Example I. EXAMPLE IV The procedure of Example I is repeated except that a comparable amount of the sulfonic acid of a viscous liquid by-product of alkylbenzene manufacture having an average molecular weight of 335 is used in place of dodecylbenzene sulfonic acid. Using 10% by weight of water in place of 7.5% ethanol provides a dark, homogeneous, liquid, ,surfactant composition which is physically and chemically stable, showing no phase separation or gelling in the peviously described aging tests. EXAMPLE V The procedure of Example I is repeated except that a comparable amount of the sulfonic acid of an alkylbenzene having an average molecular weight of 261 is used in place of the dodecylbenzene of average molecular weight of 236. Using 7.5% by weight of 95% ethanol provides a homogeneous,liquid surfactant composition which is physically and chemically stable,showing no phase separation or gelling in the aging tests. EXAMPLE VI The procedure of Example I is repeated except a like amount of nonylphenol ethylene oxide condensate containing an average of 4 moles of ethylene oxide per mole of nonylphenol is used in place of the condensate of 10 moles ethylene oxide. Using 10% by weight ethanol provides a homogeneous, liquid surfactant composition which has a clear point below OOC and shows no phase separation or gelling in the aging tests. EXAMPLE VII The procedure of Example I is repeated except that a like amount of dodecylphenol ethylene oxide condensate containing an average of 6 moles of ethylene oxide per mole of dodecylphenol is used in place of nonylphenol condensate of 10 moles ethylene oxide. Using 10t by weight ethanol provides a homogeneous, liquid surfactant composition having a clear point below OOC and showing no phase separation or gelling in the aging 'tests. EXAMPLE VIII The procedure of Example I is repeated except that a like amount of dodecylphenol ethylene oxide condensate containing an average of 9-10 moles of ethylene oxide per mole of-dodecylphenol is used in place of the nonylphenol condensate of 10 moles of ethylene oxide. Using 10% by weight ethanol provides a homogeneous, liquid surfactant composition having a clear point below ObC and showing no phase separation or gelling in the aging tests. EXAMPLE IX A surfactant composition of nonionic and anionic components in the weight ratio of 3 to 1 was prepared using the procedure of Example I with 6 parts by weight of nonylphenol ethylene oxide condensate containing an average of 10 moles of ethylene oxide per mole of nonylphenol, 1.37 parts by weight of the sulfonic acid of dodecylbenzene having an average molecular weight of 236 and 0.7 parts by weight of triethanolamine. The addition of 5% by weight water, as solvent, provides a homogeneous, liquid surfactant composition having a clear point below OOC. The composition is physically and chemically stable showing no phase separation or gelling in the aging tests. EXAMPLE X A surfactant composition of nonionic and anionic components in the weight ratio of 1 to 3 was prepared using the procedure of Example 1 with 2 parts by weight of nonylphenol ethylene oxide condensate containing an average of 10 moles of ethylene oxide per mole of nonylphenol, 4 parts by weight of the sulfonic acid of dodecylbenzene, having an average molecular weight of 236 and 2 parts by weight of triethanolamine. The addition of 10% by weight ethanol, as solvent, provides a homogeneous, liquid surfactant composition which is physically and chemically stable showing no phase separation or gelling in the aging tests. The highly concentrated surfactant compositions represented by the foregoing examples demonstrate highly effective compositions which are chemically and physically stable. The high-active level, at least 90% by weight, is particularly advantageous for processing other materials where the surfactant properties are desired in the formulation of e.g. detergents, cleaners or emulsions. The stability of these concentrated surfactant composi fions distinguishes them from other nonionic/anionic concentrates as shown in Examples XI and XII. EXAMPLE XI The procedure of Example I is repeated except that the alkanolamines used in compositions of Examples I through VIII were replaced by stoichiometric amounts of sodium hydroxide. The resultant mixtures for the most part exhibit adequate fluidity but all are cloudy and separate into phases upon storage at room temperature. EXAMPLE XII The procedure of Example XI is repeated using magnesium oxide in place of the sodium hydroxide as replacement for the alkanolamines. The resultant mixtures solidify upon standing for several days at room temperature. The highly advantageous properties of the liquid surfactant compositions for stabilizing pulverized coal in fuel oil mixtures of the present invention is demonstrated in the following example and tables. EXAMPLE XIII A uniform solution is made by mixing 0.25 parts by weight of the surfactant composition with 2.0 parts by weight of water. This solution is then mixed th 67.75 parts by weight of a commercially available No. 6 (Bunker C) fuel oil using efficient stirring. Then, 30 parts by weight of a pulverized coal wherein about 70% of the coal is less than about 74 microns diameter are added and stirred until a smooth, lump-free slurry is obtained. The slurry is transferred into a thermostated glass column about 50 centimeters high and 2.5 centimeters in diameter and the mixture is left in a quiescent state for a certain period of time, typically 24, 48 or 96 hours, at a controlled temperature usually 600C. At the end of this time, the percentage of coal in the bottom portion or top portion, or both, is determined and these measurements are used to evaluate the surfactant stabilizers. In Table I are the results of slurry stability tests demonstrating the effectiveness of aniqnic tri- ethanol amine salt of dodecylbenzene (MW 236) sulfonic acid (DBSA-TEA) and representative nonionic, nonylphenol ethylene oxide condensate containing 10 moles of ethylene oxide per mole of nonylphenol (NPlOEO); with 4 moles of ethylene oxide (NP4EO); and dodecylphenol with 7 moles of ethylene oxide (DP7EO). TABLE I Coal-Oil Mixture Stability 30%coal/2% added water/0.25 surfactant/24 hrs. at 6O0C. SURFACTANT % COAL % COAL TEST NONIONIC / ANIONIC RATIO BOTTOM TOP * CONTROL --- --- --- 63.4 6.1 3 1 --- DBSA-TEA --- 38.0 18.6 2 2 NPlOEO --- --- 42.0 20.1 2 3 NP4EO --- --- 58.6 17.2 3 4 DP7EO --- --- 47.6 18.9 2 5 NPlOEO / DBSA-TEA 1:3 33.2 23.8 1 6 NPlOEO / DBSA-TEA 1:1 33.4 21.8 7 NPlOEO / DBSA-TEA 3:1 34.3 21.2 1 8 NP4EO / DBSA-TEA 1:1 33.4 20.0 1 9 DP7EO / DBSA-TEA 1:3 33.3 22.4 1 10 DP7EO / DBSA-TEA 1:1 32.1 22.9 1 11 DP7EO / DBSA-TEA 3:1 34.1 22.0 1 * Redispersibility of Coal-Oil Mixture 1 = readily redis persible, soft settling; 2 = redispersible, medium settling; 3 = hard packed, not redispersible. Using the procedure of Example XIII, the advantages of using the surfactant composition for stabilizing coal in fuel oil mixtures over the effect of the added water alone is demonstrated in Table II. TABLE II Coal-Oil Mixture Stability 30X Coal/2XWater/0.25% Surfactant/24 hrs. at 600C. % Improvement Surfactant Coal % Coal % Coal over Water Composition Type Bottom Top Bottom Top 2% Water Ill.* 56.0 10.7 2% Water W. Va.** 52.2 14.1 Example I Ill. 33.4 21.8 87 58 1l Ir W. Va. 31.4 24.9 94 68 Example II Ill. 33.0 20.8 86 52 " " W. Va. 32.5 27.3 89 83 Example III Ill. 31.7 21.7 93 57 II II W. Va. 32.9 28.8 87 92 Example IV Ill. 32.0 26.8 92 83 II II W. Va. 30.8 28.4 96 90 Example V Ill. 33.5 21.5 86 56 II 11 W. Va. 32.8 24.5 87 65 * Illinois &num;6 seam bituminous coal. ** West Virginia bituminous coal. Similar improved results are obtained using the surfactant compositions to stabilize fuel oil mixtures containing Kentucky bituminous coal and Pennsylvania bituminous and sub-bituminous coal. The advantages of the instant surfactant compositions at various coal levels in fuel oil mixtures is demonstrated in Table III. TABLE III Coal*-O;l Mixture Stability 2% added water / 0.25% surfactants 30% Coal 40% Coal 50% Coal 24 hrs./6O0C 48 hrs./600C 96 hrs./710C Surfactants %Bottom %Top %Böttom %Top bottom %Top Control 2% Water 56.0 10.7 59.6 21.2 63.9 29.0 NPlOEO - 42.0 20.1 66.5 21.6 55.0 38.3 DP7EO 47.6 18.9 66.5 21.9 63.1 24.5 DBSA-TEA 38.0 18.6 47.8 24.5 55.6 45.7 EXAMPLE I 33.4 21.8 43.8 28.8 51.9 48.2 EXAMPLE VII 32.1 22.9 43.4 29.6 52.0 50.0 *Illinois 26 seam bituminous coal. Although the invention has been described in terms .of specific embodiments which are set forth in considerable detail, it should be understood that this is by way of illustration only and that the invention is not necessarily limited thereto since alternative embodiments and operating techniques will become apparent to those skilled in the art in view of the disclosure. Accordingly, modifications are contemplated which can be made without departing from the spirit of the described invention.

Claims: CLAIMS 1. A liquid surfactant composition comprising: (A) a nonionic component of alkylphenol polyoxyalkylene ether; (B) an anionic component of alkanolamine salt of alkylaryl sulfonic acid; and (C) not more than about 10 weight percent solvent,- wherein the weight ratio of (A) to (B) varies between about 1 to 3 to about 3 to 1. 2. A composition of Claim 1, wherein the alkylphenol polyoxyalkylene ether is selected from condensation products of Cos 12 alkylphenols condensed with an average in the range of about 4 to about 12 moles of C23 alkylene oxide. 3. A composition of either Claim 1 or Claim 2 wherein the alkanolamine salt of alkylaryl sulfonic acid is selected from the group consisting of mono-, di- and tri-C1 alkanolamine salt of C10-15 alkylbenzene sulfonic acid and mixtures thereof 4. A composition of any of the preceding claims, wherein the solvent is selected from the group consisting of water, C13 alcohols, formamide and mixtures thereof. 5. A composition of Claim 3, wherein C1O 15 alkylbenzene has an average molecular weight in the range of 231 to 335. 6. A composition of any of the preceding claims, wherein (A) is nonylphenol condensed with an average of 10 moles ethylene oxide and (B) is triethanolarnine salt of C1015 alkylbenzene sulfonic acid. 7. A composition of Claim 6, wherein the solvent is ethanol. 8. A composition of either Claim 6 or Claim 7, wherein C 15 alkylbenzene has an average molecular weight in the range of 231 to 241. 9. A process for preparing a concentrated liquid nonionic/anionic surfactant composition which comprises admixing a nonionic component of alkylphenol polyoxyalkylene ether with an alkylaryl sulfonic acid and adding to said admixture mono-1 di- or tri-C 3 alkanol- amine in an amount sufficient to neutralize the alkylaryl sulfonic acid. 10. A process of Claim 9, wherein the amount of said alkanolamine is sufficient to provide a composition pH in the range of 7 to 8. 11. A process of either Claim 9 or Claim 10, wherein no more than 10% by weight of solvent is added. 12. A process of any of Claims 9 to 11, wherein the alkanolamine is triethanolamine. 13. A process of any of Claims 9 to 12, wherein the alkylphenol polyoxyalkylene ether is selected from the group consisting of condensation products of C8 12 alkylphenols condensed with an average in the range of about 4 to about 12 moles of ethylene oxide and the alkylaryl sulfonic acid is selected from the group consisting of C1O 15 alkylbenzene sulfonic acids. 14. A method of stabilizing pulverized coal in fuel oil mixtures which comprises admixing about 30 to about 50 parts by weight pulverized coal, about 70 to about 50 parts by weight fuel oil, not more than about 10 parts by weight added water and a sufficient amount to stabilize the mixture of a composition of Claim 1. 15. A method of Claim 14, wherein the amount to stabilize the mixture is not more than about 1% by weight of the mixture. 16. A method of either Claim 14 or Claim 15, wherein in the amount of added water is from 1 to about 5 percent by weight of the mixture. 17. A method of any of Claims 14 to 16, wherein the composition to stabilize the mixture is the composition of Claim 3. 18. A stabilized mixture which comprises about 30 to about 50 parts by weight pulverized coal, about 70 to about 50 parts by weight fuel oil, not more than about 10 parts by weight added water and a sufficient amount to stabilize the mixture of the composition of Claim 1. 19. A mixture of Claim 18, wherein the composition to stabilize the mixture is a composition of Claim 3. 20. A mixture of Claim 18, wherein the composition to stabilize the mixture is a composition of Claim 6.

Inventors: DOLAN, MICHAEL JOHN
Applicants: MONSANTO COMPANY
Application year: 1982
Main classification: C10L1
IPC codes: C10L1, B01F17