GB1601174A - Combustible emulsions or dispersions - Google Patents

Description

(54) COMBUSTIBLE EMULSIONS OR DISPERSIONS (71) We, LANKO, INC., a corporation organised and existing under the laws of the State of Pennsylvania, United States of America, of Two Penn Center Plaza, Philadelphia, Pennsylvania, United States of America, 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 invention relates to combustible emulsions or dispersions for use in industrial processes and in particular to emulsions formed of hydrocarbon and/or carbonaceous materials and water. Emulsions of this type are known as fuels, see for example US patents 3206410, 3311561, 3346494, 3442842, 3355394, 3527581, 3645903 and 3876391.

It is an object of this invention to provide an improved combustible hydrocarbon and/or carbonaceous material and water emulsion or dispersion having improved properties, especially long term stability.

According to the invention, a combustible emulsion or dispersion comprises a hydrocarbon and/or carbonaceous material, and water, a hydrophilic-lipophilic agent having a molecular weight of from 200 to 10,000 and a water-soluble or water-swellable material having a molecular weight exceeding 500,000.

While we do not wish to be bound in any way by the following theory, it is believed that within the emulsion or dispersion, the high molecular weight material provides a matrix and the water component is connected to the matrix and the low molecular weight agent links the water phase and the hydrocarbon and/or carbonaceous material phase. In this way a stable system is built up and maintained, and this may account for the long term stability of the emulsions. Because the emulsions or dispersions are stable, they may be used in addition to, or substitution for, ordinary heating or other fuel oil.

Preferably the content of the water-soluble or water-swellable material exceeds that of the hydrophilic-lipophilic agent which is an advantage where such agents are relatively more expensive. The concentration of both the hydrophilic-lipophilic agent and the water-swellable or water-soluble material is preferably very low. The content of the hydrophilic-lipophilic agent may range from 1 gram/litre to 4 gram/litre relative to a liquid hydrocarbon. Most preferably the content of water is up to 40% by volume.

The invention further includes a method of making a combustible emulsion or dispersion, comprising mixing together with agitation a hydrocarbon and/or carbonaceous material water, a hydrophilic-lipophilic agent having a molecular weight of from 200 to 10,000 and a water-soluble or water-swellable material having a molecular weight exceeding 500,000.

Depending on their solubility, the hydrophilic-lipophilic agent may be added to either the hydrocarbon or the water or both.

Most preferably the internal phase of the emulsion comprises droplets or particles having a particle size exceeding 1400 Angstroms. Such emulsions, which may be termed macroemulsions tend to have a milky appearance. If a coal is used, they appear black.

It has further been found that by a careful selection of the choice of agent, water soluble or water swell able material and hydrocarbon and/or carbonaceous material and also their relative proportions it is possible to provide an emulsion having a desired long term stability, level of viscosity and water content. The viscosity may range from about one to about 50 centistokes; generally the lower the viscosity the shorter the long term stability of the emulsion. Generally the water content is from 1% to 40% by volume, preferably 1 to 20% and content of water may be within the internal phase or the external phase of the emulsion. Where the water is in the internal phase it may make up from 70% to 90% thereof: below 30% the water is a low internal phase, from 30% to 70% a medium internal phase and above 70% a high internal phase.

Preferred hydrophilic-lipophilic agents have a molecular weight in the range of 200 to 700. Examples include salts of dioctylsulphosuccinic acid such as the sodium salt; salts of decylbenzenesulphonic acid such as the sodium salt; salts and esters of dodecylbenzenesulphonic acid such as the calcium salt and the alkylamine ester; alkylphenoxypolyalkoxyalkanols such as octylphenoxypolyethoxyethylene ethanol or a polyoxy analogue; oleates such as sorbitan sesquioleate and palmitates such as polyoxyethylene sorbitan monopalmitate; detergents such as Ivory liquid detergent, US patents 3024273, 3179598, 3179599 and 3793233.

The agent may be soluble in either the water or hydrocarbon, and may be ionic or non-ionic.

Preferred high molecular weight materials include cross-linked polymers which tend to be water-swellable and substantially non-cross-linked polymers which tend to be watersoluble. The material is preferably a homo or copolymer of a substituted or unsubstituted amide, amine, imine, ethylene-imine or ethoxy residue. Preferred are polyacrylamides, polyacrylonitriles and polyoxyethylenes. These may be highly or partially hydrolysed, or they may be quaternised.Examples of particularly preferred materials are a waterswellable poly (acrylamide/sodium acrylate). in partially cross-linked form (US patent 3669103); a water-swellable hydrolysed starch polyacrylonitrile graft copolymer (US patent 3935099); a water-soluble high molecular weight polyacrylic acid in completely neutralised form, (US patent 2798053) a polyoxyethylene polymer having a mean molecular weight over 500,000 (Union Carbide Company's Polyox Coagulant); and partially hydrolysed polyacrylamides (US patent 3825069).

Preferred hydrocarbons or carbonaceous material include gasoline, aviation fuel, heating oil, diesel oil and crude oil, coals, preferably of a particle size less than 60 mesh and most preferably between 200 and 325 mesh (US sieve size) including bituminous coal, lignite and solvent-refined coal; and carbon.

The coal or carbon may be mixed with lime, chalk, alumina and preferably in slurry form.

Where the emulsion formed comprises a suspension of coal particles in a fuel oil in the presence of water it has been observed that improved combustion results. This is believed to be due to a superheating of the water in the emulsion which causes the oil particles to be blown apart. Such an emulsion can contain as much as 50% or more by weight coal particles with very little hydrocarbon oil.A particularly preferred emulsionis 50% by weight coal particles, 40% by weight heating oil and 10% by weight of water.

It is possible to incorporate additives in the emulsions. For example the viscosity and the volatilitv of the emulsions can be controlled by alcohols such as methyl, ethyl or isopropyl alcohol and ketones such as acetone and ethers. Salts such as sodium chloride may also be present. The aluminium salts of naphthenic acid and coconut oil acids or a mixture of naphthenic acid and unsaturated acids may be present to modify the hydrocarbon.

The formed emulsions may be used as internal combustion fuels, aviation fuels, domestic heating fuels, and turbine fuels.

The invention is illustrated by the following examples which are given' by way of illustration only.

Example 1 Sodium dioctyl sulphosuccinate was added to AMOCO lead-free gasoline, average octane rating 97.5, at the rate of 3.75 gm/litre. Dx-1300 polymer (Dow Chemical Company), and the sodium salt of a water-soluble high molecular weight polyacrylic acid (Carbopol 941 - Carbopol is a registered trade mark - BF Goodrich Chemical Company US patent 2798053) were added to water at the rates of 0.7 gm/litre and 0.5 gm/litre, respectively. 75 parts by volume of the gasoline mixture were shaken with 25 parts by volume of the water and a stable emulsion was formed. The emulsion was left standing at room temperature and the following noted After one month no separation After four months a water layer, 3.7% of the total volume, was formed After nine months the water layer was 5.6% of the total volume.

The viscosity of the emulsion was lowered by adding 10% by volume of ethyl alcohol, and the product was used as a fuel in a single cylinder internal combustion engine which was run at full power over a prolonged period of time using that fuel.

Example 2 Sodium dioctyl sulphosuccinate was added to AMOCO lead-free gasoline, average octane rating 88 at the rate of 3.75 gm/litre. (AMOCO is a Registered Trade Mark) A water swellable hydrolysed starch polyacrylonitrile graft copolymer SGP-5025 (General Mills Chemicals, Inc. US patent.3935099) was added to water at the rate of 1 gm/litre. The gasoline mixture and the water mixture were shaken together to form a stable emulsion of milk-like appearance. The emulsion was left standing at room temperature, and the following noted After 30 days no separation After 100 days a water layer about 0.5% of the total volume was formed.

Example 3 The method of Example 1 was repeated but the water contained only the Carbopol 941 at the rate of lgm/litre, and a stable emulsion of milk-like appearance was formed. On standing at room temperature, the following was noted After 2 weeks no separation After 100 days a water layer 3.3% of the total volume was formed.

The procedures of the foregoing Examples were repeated using different hydrocarbons, as follows Fuel Oil No 1 (A.S.T.M. classification) Fuel Oil No 2 (A.S.T.M. classification) Jet Engine Fuel JP4 (A.S.T.M. classification) Angolan crude oil, untreated In each case an emulsion of prolonged stability was formed.

Example 5 Sodium dioctyl sulphosuccinate was added to No 2 Fuel Oil at the rate of 3.75 gm/litre.

Isopropyl alcohol was added to bituminous coal powder. U.S. sieve size minus 325 mesh, to wet part of the powder. The oil and the coal were mixed together in the proportion of 50:30 by weight to form a black asphalt-like liquid. Carbopol 941 and XD-8992 (Dow Chemical Company) were added to water each at a rate of 1 gm/litre and 20 parts of the formed water mixture was added to the black liquid with stirring to form a fuel oil slurry comprising by weight 50 parts fuel oil, 30 parts coal and 20 parts water. The slurry was left standing for 45 days at room temperature and was found to be stable. Then it was kept at -12 C for 27 hours and at 85" - 100"C for 4 hours when only 3% of the fuel oil separated out.

Example 6 Sodium dioctylsulphosuccinate was added to Angolan light crude oil at the'rate of 3.75 gm/litre. This was then mixed with the wetted coal powder described in Example 5 in a weight ratio of 44.5:46 to form a black liquid. To the mix was added 10 parts by weight of the water mixture described in Example 5 with stirring. A homogenous black slurry comprising 46 weight parts carbon, 44.5 parts of crude oil and 9 parts water, was formed and this was found to have a long storage life.

Example 7 (i) Sodium dioctylsulphosuccinate was added to AMOCO lead-free gasoline, average octane rating 88, at the rate of 3.75 gm/litre. 80 ml of the gasoline were mixed with 20 ml of water using a magnetic stirrer operated in steps each of which comprised 15 seconds stirring followed by 5 seconds standing or swirling by hand. It was necessary to perform these steps six times before a stable gasoline-in-water emulsion was formed.

(ii) A water swellable polyacrylamide/sodium acrylate (Dow Chemical Company XD 8992), US patent 3669103) was added to distilled water at the rate of 0.63 gm/litre. 18 ml of the water was added to 73 ml of the gasoline mix defined at (i) above, and the mix was subjected to the mixing steps as there defined. A stable emulsion was formed after only two such steps.

(iii) A water swellable hydrolysed starch polyacrylonitrile graft copolymer (US patent 3935099) was added to distilled water at the rate of 1 gm/litre. 20 ml of the water was added to 80 ml of the gasoline mix defined at (i) above, and the mix was subjected to the mixing steps as there defined. A stable emulsion was formed after only two such steps.

Example 8 a) The sodium salt of dioctylsulphosuccinic acid (American Cyanamid OT-100) was added to AMOCO lead-free gasoline, average octane rating of 88, at the rate of 3.75 gm/litre. A water-swellable hydrolysed starch polyacrylonitrile graft copolymer (General Mills Chemicals Inc., SG-P5025, US patent 3935099) was added to distilled water at the rate of 1 gm/litre. 100 ml of the gasoline mixture was added to 25 ml of the water and the mix was subjected to the stirring steps of Example 7. A stable emulsion was formed after only two such steps. The emulsion had a viscosity of about 3 centistokes. 6 ml of the emulsion was centrifuged for 5 minutes at 200g, and 0.84 ml of liquid separated out.

b) The mix defined at (a) above was subjected to six stirring steps at double the stirring speed and an emulsion having a viscosity of about 12 centistokes was formed. When centrifuged as before, only 0.3ml of liquid separated out.

c) The sodium salt of sulphosuccinic acid (American Cyanamid OT-100), was added to AMOCO lead-free gasoline, average octane rating 88, at the rate of 3.75gm/litre. The sodium salt of a water-soluble high molecular weight polyacrylic acid (B.F. Goodrich Carbopol 941, US patent 2798053), was added to distilled water at the rate of 1 gm/litre.

80ml of the gasoline mixture and 20 ml of the water were subjected to stirring as in Example 7, and ten such stirring steps were required followed by six more at double the stirring speed to form an emulsion having a viscosity of about 25 centistokes. When centrifuged as in Example 8(b). only 0.48ml of liquid separated out.

d) A water swellable hydrolysed starch polyacrylonitrile graft copolymer (General Mills SG-P5025. US patent 3935099) and the sodium salt of a water soluble high molecular weight polyacrylic acid (B.F. Goodrich Carbopol 941, US patent 2798053) were each added to distilled water at the rate of 1 gm/litre. 10ml of each solution was added to the gasoline mixture of Example 8(c), and after stirring as in Example 8(b) three times an emulsion having a viscosity of about 13 centistokes was formed. When centrifuged as in Example 8(a), only 0.48ml of liquid separated out.

e) A water swellable polyacrylamide/ sodium acrylate (Dow Chemical Company XD-8992, US patent 3669103) and the sodium salt of a water-soluble high molecular weight polyacrylic acid (B.F. Goodrich Carbopol 941, US patent 2798053), were both added to distilled water at the rate of lgm/litre. The sodium salt of dioctylsulphosuccinic acid (American Cyanamid OT-100) was added to AMOCO lead-free gasoline, average octane rating 97.5, at the rate of 3.75gm/litre. 25ml of the water and 75 ml of the gasoline together with one litre of water were stirred at five times the rate of Example 8(a) to form an emulsion having a viscosity of about 50 centistokes. When centrifuged as in Example 8(a), only 0.12 ml of liquid separated out. The emulsion was left standing at room temperature for about three months after which about 0.1 ml of water separated out.This test shows a good correlation in results between the accelerated centrifuging test for stability and long term standing.

Example 9 a) The sodium salt of dioctylsulphosuccinic acid (American Cyanamid OT-100) was added to AMOCO lead-free gasoline average octane rating 88, at the rate of 3.75 gm/litre. 80 ml of the gasoline mixture and 20 ml of plain water were subjected to the procedure of Example 8(b) above and an emulsion was formed after nine such stirring steps. After a further four stirring steps the emulsion was found to have a viscosity of about 4 centistokes and when subjected to centrifuging as in Example 8(a) above, 0.54 ml of liquid separated out.

b) The procedure of Example 9(a) was repeated using 20 ml of water containing 1 gm/litre of a water-swellable hydrolysed starch polyacrylonitrile graft copolymer (General Mills SGP 5025, US patent 3935099) in place of the plain water. After the same stirring, the emulsion had a viscosity of about 8 centistokes and when centrifuged as in Example 7(a), 0.54 ml of liquid separated out. This shows that the presence of the high molecular weight material influences the viscosity of the emulsion.

Example 10 a) The sodium salt of dioctylsulphosuccinic acid was added to AMOCO lead-free gasoline, average octane rating 88, at the rate of 50 gm/litre. 120 ml of the gasoline was mixed with 30 ml of distilled water and the stirring steps of Example 8(a) were performed twice to form a water-in-gasoline emulsion having a viscosity of about one centistoke. When centrifuged as in Example 8(a) after 7 days storage at room temperature, 1.5% of the water separated out.

b) The procedure of Example 10(a) was repeated using 30 ml of water containing 1 gm/litre of a water-swellable polyacrylamlde/ sodium acrylate partially cross-linked polymer (Dow Chemical Company XD 8992), instead of the distilled water, and a similar emulsion to that obtained above was formed. This shows that the low molecular weight agent and the high molecular weight polymer intereact even at low concentrations.

Example 11 Compositions were made up and tested as shown in the accompanying Table using the methods disclosed above to assess the effect on the emulsions of various additives. It was observed that emulsions could not be formed in the presence of calcium chloride, nor in the presence of a high concentration of sodium chloride. Emulsions could however be formed in the presence of methanol.

Water mixture Gasoline mixture Additive Mixing method Mixing Emulsion Separation on time viscosity centrifuging a 20 ml water containing 80 ml of the gasoline nil as Exmple 8(a) 3 mins 4 0.7 ml 0.34 gm/litre water- mixture of Example 8(a) swellable polymer of Example 2 b as (a) as (a) l ml of methanol as Example 8(a) 30 sec 3 0.9 ml c 20 ml of water containing 80 ml of the gasoline nil magnetic 60 sec 7 0.14 ml l gm/litre water-sweltable mixture of Example 8(a) stirring polymer of Example 2 containing 1.2 gm/litre of low molecular agent d as (c) as (c) l ml of as (c) 15 sec 3 0.8 ml methanol e 10 ml of water containing 90 ml gasoline mixture nil as (c) 5 min 16 0.3 ml 0.34 gm/litre water of Example 8(a) swellable polymer of Example 2 70 ml of the gasoline nil as (c) 2 min 3 1.1 ml f 30 ml of water mixture of Example 8(a) g as (a) as (a) 0.55 ml of as (a) NO EMULSION COULD BE PRODUCED calcium chloride h as (a) as (a) l ml of as Example 4 3 0.19 ml sodlum chloride 8(a) stirring steps i 18 ml of the solution as (a) 2 ml of as (a) NO EMULSION COULD BE PRODUCED (a) sodium chloride Example 12 a) A polyoxyethylene molecular weight over 500,000 (Union Carbide Company's POLYOX -Registered Trade Mark) was added to water at the rate of 1 gm/litre. The sodium salt of dioctylsulphosuccinic acid (American Cyanamid OT-100) was added to AMOCO lead-free gasoline, average octane rating 88 (AMOCO is a registered Trade Mark), at the rate of 3.75 gm/litre. 20 ml of the water and 80 ml of the gasoline mixture were mixed in the method of Example 7(i) and after 15 such steps an invert emulsion was formed. Stirring was performed for four further steps. The formed emulsion had a viscosity of about 10 centistokes.When centrifuged about 0.33 ml of liquid separated out.

b) The procedure of Example 12(a) was repeated using 10 ml of the water solution and 10 ml of a water solution containing 1.5 gm/litre of water-swellable polyacrylamide/ sodium acrylate partially cross-linked polymer (Dow Chemical Company XD 8992, US patent 3669103). The emulsion was formed in two stirring steps and had a viscosity of about 10 centistokes. When centrifuged, about 0.42 ml of liquid separated out.

c) A water swellable hydrolysed starch polyacrylonitrile graft polymer (General Mills Company SG-P 5025, US patent 3935099) was added to water at the rate of 1 gm/litre. The sodium salt of decylbenzene sulphonic acid (Arco Chemical Company's ULTRAWET-DS) was added to AMOCO lead-free gasoline, average octane rating 88, at the rate of 3.75 gm/litre. 20 ml of the water and 80 ml of the gasoline was stirred in a magnetic stirrer at about 60% full power to produce an emulsion. Stirring was continued for a further 30 seconds. The emulsion had a viscosity of about 8 centistokes, and when centrifuged about 0.8 ml of liquid separated out.

Example 13 Sodium chloride was present in the following Examples to prevent the formation of a high internal phase ratio emulsion and to ensure the formation of a water-in-hydrocarbon emulsion. In each case stirring was done using a magnetic stirrer at full power.

a) 3 ml of water containing sodium chloride concentration 2 gm/100 ml, 14 ml of water containing, swellable polyacrylamidel sodium acrylate partially cross-linked polymer (Dow Chemical Company XD 8992, US patent 3669103) (concentration 1.5 gm/litre), 14 ml of water containing the sodium salt of a high molecular weight polyacrylic acid (B.F. Goodrich Carbopol 941, US patent 2798053) (concentration 1 gm/litre) and 90 ml of AMOCO lead-free gasoline containing the sodium salt of decylbenzenesulphonic acid (Arco Chemical Company's ULTRAWET-DS) average octane rating of gasoline 88, were mixed together to give an emulsion of about 1 centistoke. The emulsion was left standing for seven weeks and there was no separation of the liquids.

b) 18 ml of distilled water, 5 ml of water containing water-swellable hydrolysed starch polyacrylonitrile graft polymer (General Mills Company SG-P 502S, US patent 3935099) at 1 gm/litre; 0.75 ml of octylphenoxypolyethoxyethanol (Rohm & Haas Company's TRITON X45); 1.5 ml of calcium dodecylbenzene sulphonate and alkylphenoxy polyoxyethylene ethanol (Stepan Company's TOXIMUL MP) and 72 ml of AMOCO lead-free gasoline average octane rating 88, were mixed together to form an emulsion which was similar to that of Example (a) above. (TRITON and TOXIMUL are Registered trade marks).

c) 3.5 ml of water containing 1.5 gm/litre of swellable polyacrylamide sodium acrylate partially cross-linked polymer (Dow Chemical Company XD 8992, US patent 3669103), 3.5 ml of water containing 1 gm/litre of the sodium salt of a high molecular weight polyacrylic acid (B.F. Goodrich Carbopol 941, US patent 2798053), 1 ml of octylphenoxypolyethoxy ethanol (Rohm & Haas TRITON X45). 1.5 ml of calcium dodecyl benzene sulphonate and alkyl phenoxy polyoxyethylene ethanol (Stepan Company TOXIMUL MP), 87 ml of AMOCO lead-free gasoline average octane rating 88, were mixed together to form an emulsion which was similar to that of Example (a) above.

Example 14 A water swellable polyacrylamide/ sodium acrylate partially cross-linked polymer (Dow Chemical Company XD 8992, US patent 3669103) was added to water at the rate of 1.5 gm/litre. The sodium salt of dioctylsulphosuccinic acid (American Cyanamid OT-100) was added to Angolan crude gasoline at the rate of 4 gm/litre. An invert emulsion was formed of 10 ml of the water and 90 ml of the gasoline. On standing for six days, less than 3 ml of water separated out.

Example 15 A water swellable polyacrylamidel sodium acrylate partially cross-linked polymer (Dow Chemical Company XD 8992; US patent 3669103) was added to water at the rate of 1.5 gm/litre.

The sodium salt of a high molecular weight polyacrylic acid (B.F. Goodrich Carbopol 941, US patent 2798053) was added to water at the rate of 1 gm/litre. 5 ml of each solution, 11 ml of No 6 fuel oil (viscosity of 126 Furol at 1200F) and 0.5 ml of alkylamine dodecylbenzene sulphonate (Stepan Chemical Company Ninate 411) were mixed in stages with 80gm bituminous coal, No 6 Illinois, - 200 mesh sieve size. The first 60 mg of the coal was stirred in by hand and the balance then added following which the mix was stirred at 600 rpm and then heated to about 1300F for 14 minutes. A stable coal-in-water slurry was formed.

Example 16 a) Ten ml of distilled water were mixed with 100 ml of No 6 fuel oil (126 Furol at 1260F) with a glass stirrer at about 600 rpm for 5 min. When 60 ml of the oil was poured through a standard funnel at 23do, it took 30 seconds to form a thin filament of oil and a further 30 seconds to complete the pour. The water/oil mixture took about one hour to drain from the standard funnel.

b) The procedure of Example 13(a) was repeated using, instead of the 10 ml of distilled water. a solution containing a water swellable polyacrylamide/ sodium acrylate partially cross-linked polymer (Dow Chemical Company XD 8992, US patent 3669103), and the sodium salt of a water-soluble high molecular weight polyacrylic acid (B.F. Goodrich Carbopol 941, US patent 2798053) each in a concentration of 1.5 gm/litre and about 0.3 gm of an alkylamine dodecylbenzene sulphonate (Stepan Chemical Company, Ninate 411).

The formed emulsion took 23 seconds to form the filament and a further 30 seconds to complete the pour. About 90% of the mixture drained from the funnel in about one second.

Example 17 To a Waring blender was added 7 ml of a water-swellable polyacrylamide/ sodium acrylate partially cross-linked polymer (Dow Chemical Company XD 8992, US patent 3669103) in distilled water at a concentration of 1.5 gm/litre, 0.5 ml of alkylamine dodecylbenzene sulphonate (Stepan Chemical Company, Ninate 411), 91.5 ml of AMOCO lead-free gasoline average octane rating 88, and 3 ml of distilled water.

The blender was operated at half power for five minutes and a very stable water-in-gasoline emulsion was formed. On storage less than 0.1 ml of water separated out.

WHAT WE CLAIM IS: 1. A combustible emulsion or dispersion comprising a hydrocarbon and/or carbonaceous material and water, a hydrophilic-lipophilic agent having a molecular weight of from 200 to 10,000. and a water-soluble or water-swellable material having a molecular weight exceeding 500,000.

2. An emulsion or dispersion according to Claim 1, in which the content of the water-soluble or water-swellable material exceeds that of the hydrophilic-lipophilic agent.

3. An emulsion or dispersion according to Claim 1 or 2, in which the content of the hydrophilic-lipophilic agent ranges from 1 gram/litre to 4 gram/litre relative to a liquid hydrocarbon.

4. An emulsion or dispersion according to any preceding Claim, in which the hydrophilic-lipophilic agent has a molecular weight in the range of 200 to 700.

5. An emulsion or dispersion according to any preceding Claim, in which the hydrocarbon is a liquid fuel.

6. An emulsion or dispersion according to any of Claims 1, 2 or 4, in which the carbonaceous material is a coal or carbon.

7. An emulsion or dispersion according to any preceding Claim, in which the content of water is up to 40 percent by volume.

8. An emulsion or dispersion according to any preceding Claim, in which the water-soluble or water-swellable material is selected from those specified herein.

9. An emulsion or dispersion according to Claim 8, in which more than one water-soluble or water-swellable material is present.

10. An emulsion or dispersion according to any preceding Claim, having a viscosity of from one to 50 centistokes.

11. An emulsion or dispersion according to Claim 10, including as viscosity adjusters an alcohol or ketone.

12. An emulsion according to any preceding Claim, in which the internal phase of the emulsion comprises droplets or particles exceeding 1400 Angstrom units particle size.

13. An emulsion or dispersion according to any preceding Claim, including a salt such as sodium chloride.

14. An emulsion according to any preceding Claim, including 50% by weight coal, 40% by weight heating oil. and 10% by weight of water.

15. An emulsion or dispersion according to Claim 1, substantially as described and with

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (17)

**WARNING** start of CLMS field may overlap end of DESC **. gm/litre. The sodium salt of a high molecular weight polyacrylic acid (B.F. Goodrich Carbopol 941, US patent 2798053) was added to water at the rate of 1 gm/litre. 5 ml of each solution, 11 ml of No 6 fuel oil (viscosity of 126 Furol at 1200F) and 0.5 ml of alkylamine dodecylbenzene sulphonate (Stepan Chemical Company Ninate 411) were mixed in stages with 80gm bituminous coal, No 6 Illinois, - 200 mesh sieve size. The first 60 mg of the coal was stirred in by hand and the balance then added following which the mix was stirred at 600 rpm and then heated to about 1300F for 14 minutes. A stable coal-in-water slurry was formed. Example 16 a) Ten ml of distilled water were mixed with 100 ml of No 6 fuel oil (126 Furol at 1260F) with a glass stirrer at about 600 rpm for 5 min. When 60 ml of the oil was poured through a standard funnel at 23do, it took 30 seconds to form a thin filament of oil and a further 30 seconds to complete the pour. The water/oil mixture took about one hour to drain from the standard funnel. b) The procedure of Example 13(a) was repeated using, instead of the 10 ml of distilled water. a solution containing a water swellable polyacrylamide/ sodium acrylate partially cross-linked polymer (Dow Chemical Company XD 8992, US patent 3669103), and the sodium salt of a water-soluble high molecular weight polyacrylic acid (B.F. Goodrich Carbopol 941, US patent 2798053) each in a concentration of 1.5 gm/litre and about 0.3 gm of an alkylamine dodecylbenzene sulphonate (Stepan Chemical Company, Ninate 411). The formed emulsion took 23 seconds to form the filament and a further 30 seconds to complete the pour. About 90% of the mixture drained from the funnel in about one second. Example 17 To a Waring blender was added 7 ml of a water-swellable polyacrylamide/ sodium acrylate partially cross-linked polymer (Dow Chemical Company XD 8992, US patent 3669103) in distilled water at a concentration of 1.5 gm/litre, 0.5 ml of alkylamine dodecylbenzene sulphonate (Stepan Chemical Company, Ninate 411), 91.5 ml of AMOCO lead-free gasoline average octane rating 88, and 3 ml of distilled water. The blender was operated at half power for five minutes and a very stable water-in-gasoline emulsion was formed. On storage less than 0.1 ml of water separated out. WHAT WE CLAIM IS:

1. A combustible emulsion or dispersion comprising a hydrocarbon and/or carbonaceous material and water, a hydrophilic-lipophilic agent having a molecular weight of from 200 to 10,000. and a water-soluble or water-swellable material having a molecular weight exceeding 500,000.

2. An emulsion or dispersion according to Claim 1, in which the content of the water-soluble or water-swellable material exceeds that of the hydrophilic-lipophilic agent.

3. An emulsion or dispersion according to Claim 1 or 2, in which the content of the hydrophilic-lipophilic agent ranges from 1 gram/litre to 4 gram/litre relative to a liquid hydrocarbon.

4. An emulsion or dispersion according to any preceding Claim, in which the hydrophilic-lipophilic agent has a molecular weight in the range of 200 to 700.

5. An emulsion or dispersion according to any preceding Claim, in which the hydrocarbon is a liquid fuel.

6. An emulsion or dispersion according to any of Claims 1, 2 or 4, in which the carbonaceous material is a coal or carbon.

7. An emulsion or dispersion according to any preceding Claim, in which the content of water is up to 40 percent by volume.

8. An emulsion or dispersion according to any preceding Claim, in which the water-soluble or water-swellable material is selected from those specified herein.

9. An emulsion or dispersion according to Claim 8, in which more than one water-soluble or water-swellable material is present.

10. An emulsion or dispersion according to any preceding Claim, having a viscosity of from one to 50 centistokes.

11. An emulsion or dispersion according to Claim 10, including as viscosity adjusters an alcohol or ketone.

12. An emulsion according to any preceding Claim, in which the internal phase of the emulsion comprises droplets or particles exceeding 1400 Angstrom units particle size.

13. An emulsion or dispersion according to any preceding Claim, including a salt such as sodium chloride.

14. An emulsion according to any preceding Claim, including 50% by weight coal, 40% by weight heating oil. and 10% by weight of water.

15. An emulsion or dispersion according to Claim 1, substantially as described and with

reference to any one of Examples 1, 2 and 4 to 17.

16. A method of making a combustible emulsion or dispersion, comprising mixing together with agitation a hydrocarbon and/or carbonaceous material water, a hydrophiliclipophilic agent having a molecular weight of from 200 to 10,000 and a water-soluble or water-swellable material having a molecular weight exceeding 500,000.

17. A combustible emulsion or dispersion when made by the method of Claim 16.