Emulsifier and emulsions

Abstract

There is provided an emulsifier comprising at least one C.sub.8 to C.sub.18 fatty acid diethanolamide, at least one C.sub.12 to C.sub.24 fatty acid, at least one C.sub.6 to C.sub.18 alcohol ethoxylate and optionally at least one sorbitan ester and/or at least one alkylene glycol monoalkyl ether. There is additionally provided emulsions comprising a fuel, water and an emulsifier and methods of producing emulsions.

Claims

1. A composition comprising: 60-90 wt % of at least one C.sub.8 to C.sub.18 fatty acid diethanolamide; 2-10 wt % of at least one C.sub.12 to C.sub.24 fatty acid; and 5-20 wt % of at least one C.sub.6 to C.sub.18 alcohol ethoxylate; wherein said emulsifier does not comprise naphtha; and wherein the composition is useful as an emulsifier.

2. A composition according to claim 1 comprising: a fuel comprising at least one of diesel, low sulphur diesel, biodiesel and heavy fuel oil; less than or equal to 30 wt % water; and from 0.5 to 15 wt % of the emulsifier.

3. A composition according to claim 1 comprising: a fuel comprising at least one of diesel, low sulphur diesel and heavy fuel oil, wherein the fuel does not contain any bio-components; less than or equal to 20 wt % water; and the emulsifier, wherein the emulsifier:water volume ratio is from 1.5:1 to 1:2.9, and wherein the composition is a nanemulsion.

4. A method of making a nanoemulsion according to claim 3, comprising emulsifying a mixture of the fuel, water and the emulsifier using ultrasonic emulsification.

5. The composition as claimed in claim 1, wherein the fatty acid ethanolamide is derived from a natural source.

6. The composition as claimed in claim 1, wherein the fatty acid is a monounsaturated fatty acid and preferably a C.sub.14-20 monounsaturated fatty acid.

7. The composition as claimed in claim 1, wherein the alcohol ethoxylate has a HLB in the range of from 9 to 12.

8. A scavenger solution comprising: 10-40 wt % composition of claim 1; and 60-90 wt % alkylene glycol monoalkyl ether.

9. The composition of claim 1 comprising 10-30 wt % of at least one sorbitan ester.

Description

(1) The invention will be further described with reference to the following Figures:

(2) FIG. 1 shows the stability of diesel emulsions over a year;

(3) FIG. 2 shows the stability of a diesel emulsion when cooled to −20° C.;

(4) FIG. 3 shows the stability of a diesel emulsion when heated to 70° C.;

(5) FIG. 4 shows the stability of a heavy fuel oil emulsion after 9 months.

(6) The invention will be further described with reference to the following Examples.

EXAMPLES

Example 1

(7) A number of compositions were produced and tested for producing emulsions with varying amounts of water. Each composition was produced by mixing the emulsifier, blending the emulsifier with diesel and then adding water and emulsifying.

(8) The emulsifiers were made using the following ingredients:

(9) Coconut fatty acid diethanolamide (CDE) from by SABO®

(10) Oleic acid (OE) from Eastman Chemical Company

(11) Tergitol® NP-6 (nonylphenol polyethoxylate) (NP-6D) by The Dow Chemical Company

(12) Nonylphenol polyethoxylate (NP-6G) by Gamma Chemical

(13) Sorbitan monooleate (SPAN 80) by CRODA®

(14) Berol 260 (C.sub.9-11 alcohol ethoxylate) (B260) by AkzoNobel®

(15) Ethylan 1005 SA (C.sub.10 alcohol ethoxylate) (E1005) by AkzoNobel®

(16) The emulsifiers used the following parts by weight.

(17) TABLE-US-00002 TABLE 1 Composition CDE OA NP-6D NP-6G SPAN 80  1* 30 20 50  2* 45 27 28  3* 65 10 25  4* 75 12 13  5 65 25 10  6 80 10 10  7 85 5 10  8 62.5 10.5 8 19  9 62 5 10 23 10 65 5 10 20 *indicates an example not within the scope of the claims

(18) 3 parts by weight of emulsifier were mixed with 89 parts by weight of diesel and water in the amounts set out in Table 2. The emulsions were formed using the specified mixer and the turbidity measured.

(19) TABLE-US-00003 TABLE 2 Composition 1* 2* 3* 3* 4* 5 6 7 8 9 10 Diesel Local Local Local Shell Local Shell Shell Shell Shell Shell Shell V-Power V-Power V-Power V-Power 50 50 50 Mixer SC SC SC U1000 SC U1000 U1000 U1000 U400 U400 U400 Turbidity @0 0.74 0.01 0.01 0.01 0.01 parts H.sub.2O @1 part H.sub.2O 0.42 0.82 >1050 4.15 4.54 4.28 0.01 1.82 2.09 @2 parts H.sub.2O 11.1 7.95 4.11 27.50 23.10 30.20 13.6 8.3 35.1 @3 parts H.sub.2O 30.5 28.1 20.6 29.6 50.80 46.60 19.1 17.5 27.9 @4 parts H.sub.2O 50.0 51.2 41 42.8 50.5 50.6 24.7 51.2 43.7 @5 parts H.sub.2O 50.9 51.3 700.0 50.5 50.6 50.7 38.8 855 50.7 @6 part H.sub.2O 58.5 51.5 0.74 50.6 50.6 45.6 72.4 >1050 405 @7 parts H.sub.2O 90.5 58.6 67 68.4 55.3 412 >1050 429 @8 parts H.sub.2O >1050 145 100 134 76.8 76.8 351 329 682 @12 parts H.sub.2O 200 @15 parts H.sub.2O 320 *indicates an example not within the scope of the claims

(20) SC is a Heidolph Silent Crusher variable speed high shear mixer.

(21) U1000 is a Hielscher UIP1000 bench top ultrasonicator.

(22) U400 is a Hielscher UP400st lab ultrasonicator.

(23) Both “local” diesel and Shell V-Power are both diesel fuels that do not contain bio components.

(24) Shell 50 is Shell V Power 50 ppm diesel which has less than 50 ppm sulphur and contains bio-components.

(25) Turbidity was measured immediately after the formation of the emulsion using the Van Walt Compact Turbimeter.

(26) The results demonstrate that the compositions of the present invention are capable of forming stable emulsions with low turbidity across a broad range of water content using low levels of the compositions. The compositions are also capable of forming stable emulsions even when the fuel is a low sulphur fuel.

Example 2

(27) Compositions were tested to measure the stability of emulsions of water and diesel containing biocomponents at higher levels of water.

(28) Composition 10 was mixed with water at a ratio of 33 parts composition to 67 parts by weight water. The mixture of water and composition were then added to Shell 50 in the amounts set out in Table 3. The mixing was undertaken at ambient temperature. The diesel/water mixture was emulsified using a U400 ultrasonicator for 1 minute. The samples were then allowed to cook to ambient temperature and transferred to a container for long term storage. The container was stored at ambient temperature at an altitude of 550 m. The ambient temperature varied from 0° C. to 37° C.

(29) The turbidity was measured immediately after emulsification and again after a few minutes once air bubbles had cleared.

(30) TABLE-US-00004 TABLE 3 Shell 50 Water/Example 10 Turbidity @0 Turbidity @2-5 (pbw) (pbw) mins mins 90 10 60.5 50.3 85 15 71.3 50.4 80 20 155 50.5

(31) The emulsions were stored for a period of greater than a year. It should be noted that storage of modern fuels for more than 6 months is not recommended. All three emulsions were stable for a year. After 15 months, the emulsion containing 10 pbw water/emulsifier had separated slightly. This was the time when the first signs of separation had started to show. 15 months is an extremely long period of stability. This is shown in FIG. 1, in which a) shows the emulsions at formation (water/emulsifier content from left to right 20, 15, 10) and b) shows the emulsions after 15 months (same order) in which the emulsion for 10 pbw water is more turbid.

(32) 5 parts by weight of Example 10 was mixed with 85 parts by weight of diesel and 10 parts by weight of water. The diesel/water/emulsifier mixture was emulsified using a U400 ultrasonicator for 1 minute. The samples were placed in a heated oven at 70° C. for 1 hour and returned to ambient temperature. The same samples were placed in a freezer at −20° C. for an hour and returned to ambient temperature.

(33) The samples are shown in FIGS. 2 and 3.

(34) It can be seen that in FIG. 2a, at −20° C., the emulsion is turbid. However, in FIG. 2b, the emulsion is clear after returning to ambient temperature without any stirring.

(35) Similarly, in FIG. 3a, at 70° C., the emulsion is turbid. However, in FIG. 3b, the emulsion is clear after returning to ambient temperature without stirring.

(36) 1 part by weight of the composition of Example 7 was mixed with 30 parts by weight of water and 69 parts by weight of heavy fuel oil at 70° C. and emulsified using a U400 ultrasonicator for 3.5 minutes. The samples were then allowed to cool to ambient temperature and transferred to a container for long term storage. The container was stored at ambient temperature at an altitude of 550 m. The ambient temperature varied from 0° C. to 37° C.

(37) The resulting emulsion remained stable for over 9 months. FIG. 4 shows the emulsion of the heavy fuel oil and water after 9 months.

Example 3

(38) A scavenger solution was prepared using Composition 7. 1 part by weight of this composition was mixed with 4 parts by weight of butyl oxitol.

(39) Testing was undertaken on Shell 500 ppm sulphur diesel in a diesel generator. The diesel generator was a 229-3 3 cylinder generator from MWM Motores Diesel Ltda.

(40) Emissions were tested for the fuel as a baseline measurement and for the fuel containing 500 ppm of the scavenger solution.

(41) The scavenger solution was mixed with the fuel ultrasonically using the U400 ultrasonicator. The generator was operated at a constant 1510 rpm. A 2° C. rise in block temperature was noted during the test which included the scavenger. A summary of the exhaust fumes can be seen in Table 4.

(42) TABLE-US-00005 TABLE 4 O.sub.2 CO CO.sub.2 NO NO.sub.x NO.sub.2 SO.sub.2 Temp ° C. % ppm % ppm ppm ppm ppm m.sup.3/s m/s Shell 50 112.14 18.46 633.4 1.61 133.6 191.7 55.9 21.7 17.3 7.7 Shell 50 + 500 107.50 19.23 445.5 1.11 89 146.8 45.2 17.0 24.4 10.8 ppm scavenger

(43) The results show a marked reduction in the amount of CO, NOx and SOx when operating with the fuel which contained the scavenger.

(44) A test was also run on the above two fuels to measure the opacity of the exhaust gas. This measurement is related to the amount of particulate in the exhaust gas. Testing was undertaken using a Texa Diesel Smoke Opacimeter. The Opacimeter provides a qualitative and partially quantitative assessment of the amount of particulate in the exhaust gas. The baseline test gave an opacity result in the range of 1.6 to 2.3%. Testing using the fuel containing the scavenger showed a 100% reduction in the opacity i.e. showed 0% opacity.

(45) It can be seen that addition of the scavenger reduces the all of the emissions including particulate emissions.

Example 4

(46) The scavenger solution of Example 3 was tested in red diesel in an amount of 500 ppm. A comparison was made with red diesel without the scavenger solution.

(47) The emissions were tested from a diesel tractor and the diesel generator used in Example 3.

(48) The results are shown in Tables 5 and 6.

(49) TABLE-US-00006 TABLE 5 Diesel + 500 ppm Parameter Units Diesel Scavenger Total Particulate Matter mg/m.sup.3 45.3 41.5 Total Particulate emission rate g/hr 5.3 4.8 PM 10 mg/m.sup.3 12.2 5.7 PM 10 emission rate g/hr 1.0 0.5 PM 2.5 mg/m.sup.3 10.63 4.1 PM 2.5 emission rate g/hr 0.91 0.4 NO.sub.2 mg/m.sup.3 655.1 697.1 NO.sub.2 emission rate g/hr 75.3 80.1 SO.sub.2 mg/m.sup.3 26.1 26.1 SO.sub.2 emission rate g/hr 3.0 3.1 CO mg/m.sup.3 903.1 763.2 CO emission rate g/hr 103.8 87.7 CO.sub.2 % v/v 2.13 2.10 O.sub.2 % v/v 17.95 17.98 Moisture % 3.8 3.0 Stack gas temperature ° C. 113 113 Stack gas velocity m/s 19.1 19.1

(50) TABLE-US-00007 TABLE 6 Diesel + 500 ppm Parameter Units Diesel Scavenger Total Particulate Matter mg/m.sup.3 16.9 14.4 Total Particulate emission rate g/hr 4 3.5 PM 10 mg/m.sup.3 PM 10 emission rate g/hr PM 2.5 mg/m.sup.3 PM 2.5 emission rate g/hr NO.sub.2 mg/m.sup.3 397.8 399.2 NO.sub.2 emission rate g/hr 100.8 101.2 SO.sub.2 mg/m.sup.3 19.5 21.6 SO.sub.2 emission rate g/hr 4.9 5.5 CO mg/m.sup.3 80.9 86 CO emission rate g/hr 20.5 21.8 CO.sub.2 % v/v 2.37 2.3 O.sub.2 % v/v 17.79 17.89 Moisture % 6.9 3.9 Stack gas temperature ° C. 117 117 Stack gas velocity m/s 25.6 25.6

(51) It can be seen that in both cases, there is a reduction in the total level of particulate matter produced with the addition of the additive.

Example 5

(52) Composition 7 was mixed with water and heavy fuel oil in the amounts set out in Table 7. The mixture was emulsified using a UIP1000 bench top ultrasonicator from Hielscher.

(53) Table 7 sets out the power required to produce a stable emulsion.

(54) TABLE-US-00008 TABLE 7 HFO (g) Composition 7 (g) Water (g) Power (Ws/g) 80 1 5 31.4 80 1 9 42.8 80 1 18 61.3 80 2 18 8.0

(55) It can be seen from Table 7 that it is possible to produce a stable emulsion in all cases. However, when an emulsion is produced using 2% of Composition 7 in combination with 18% of water, it is possible to produce an emulsion at significantly lower levels of power. This low level of power is particularly useful as the cost for producing the emulsion is relatively low. Given the energy saving and reduction in emissions identified above when using water/heavy fuel oil emulsions, it can be seen that the present invention provides a commercially beneficial method and emulsion.

(56) It is expected that this process will enable higher levels of water to be emulsified whilst requiring a low amount of power. The skilled person is capable of refining the specific amounts of the composition and the water.

(57) In this specification, unless expressly otherwise indicated, the word ‘or’ is used in the sense of an operator that returns a true value when either or both of the stated conditions is met, as opposed to the operator ‘exclusive or’ which requires that only one of the conditions is met. The word ‘comprising’ is used in the sense of ‘including’ rather than in to mean ‘consisting of’. All prior teachings acknowledged above are hereby incorporated by reference. No acknowledgement of any prior published document herein should be taken to be an admission or representation that the teaching thereof was common general knowledge in Australia or elsewhere at the date hereof.