WO1999052996A1

WO1999052996A1 - Solubilising process

Info

Publication number: WO1999052996A1
Application number: PCT/GB1999/001072
Authority: WO
Inventors: Peter Street; David Thorley
Original assignee: Coval Technologies Limited
Priority date: 1998-04-09
Filing date: 1999-04-08
Publication date: 1999-10-21
Also published as: AU3430499A; GB9807790D0; GB2336119A

Abstract

A process for combining water and petrol (gasoline) into a mixture which behaves as a clear stable homogenous solution comprises adding an effective amount of a complex mixture of higher fatty acid diethanolamides derived from coconut oil, or from its synthetic equivalent, to the water-petrol mixture. Typical proportions of the complex mixture of higher fatty acid diethanolamides, in parts by volume relative to the parts by volume of water present in the petrol, range from 0.5:1 to 2:1 and preferably range from approximately 1:1 for 1 % water contamination, approximately 1.4:1 to 1.5:1 for greater than 1 to 5 % water contamination, and 1.2:1 to 1.3:1 for greater than 5 to 15 % water contamination. The process additionally assists in the blending of petrol and water with extenders (such as ethanol), which do not have a significant water-solubilising effect.

Description

SOLUBILISLNG PROCESS

This invention relates to a process that enables water and petrol (gasoline) to be combined into a mixture which behaves as a clear stable homogeneous solution. The presence of water in petrol can cause a number of difficulties. If the water is present as an undesired contaminant, the burning of the resultant fuel is often uneven or, if the fuel is used in an engine, erratic running and stalling often results together with a serious risk of corrosion. In addition, the presence of water in petrol in amounts too small to give rise to such difficulties can still be undesirable as it can produce a lack of clarity or haze which is unappealing to the consumer. On the other hand, there are occasions when it might be desirable to be able deliberately to blend water with petrol in a stable mixture either directly as an extender or to assist in the blending of other extenders (e.g. alcohols), for the known improvements in performance and cleaner exhaust emission that may result. A large number of attempts have been made to deal with these problems by seeking to create stable emulsions of petrol with water. Such attempts, even with proprietary brands of additives, have not been wholly successful because long-term stability of the resulting mix cannot be achieved in practice. In addition, a number of prior formulations have required the use of several different additives, with associated difficulties in the storage and mixing of those components. The present invention provides a simplified process for dealing with the problem of water contamination in petrol which comprises treating the water-petrol mixture with a single readily available component in relatively low amounts.

According to the present invention there is provided a process for combining petrol and water as a stable solution that comprises adding an effective amount of a complex mixture of higher fatty acid diethanolamides derived from coconut oil, or from its synthetic equivalent, to the water-petrol mixture. The presence of other components is not precluded, but it is contemplated that the complex mixture of higher fatty acid diethanolamides would normally be added as essentially the sole additive in the process of the present invention. As already mentioned, the process of the invention can assist in the blending of petrol and water with extenders (e.g. an alcohols, such as ethanol), which do not have a significant water-solubilising effect.

The complex mixture of higher fatty acid diethanolamides derived from coconut oil, or from its synthetic equivalent, is to be understood as being "complex" in the sense that it contains a plurality of different chemicals of the diethanolamide species, including lauric, myristic, and oleic diethanolomides in significant quantities, generally together with other diethanolamides in less significant quantities, and generally a number of unidentified ingredients, possibly including such compounds as monoethanolamides and others that were present in the original biological source or were obtained as by-products during formation of the diethanaolamides. "Caflon CD" (Trade Mark) is a suitable commercially available mixture, largely composed of diethanolamides, derived from coconut oil.

As used herein the term "petrol" includes both the pure hydrocarbon fractions and petrol containing conventional additives that are present in the formulations offered for sale to the public.

The process of the present invention allows the formation of petrol-water mixtures that are true solutions or behave as such. Any mixture that is clear, homogeneous and has substantially the same stability as a true solutions is thus to be regarded as a "stable solution" for the purposes of the present invention. It was unexpected that this surfactant should be so effective, as other surfactants have been unable to achieve this effect as a single component when added in practicable amounts.

In the process according to the present invention, suitable proportions of the complex mixture of higher fatty acid diethanolamides, in parts by volume relative to the parts by volume of water present in the petrol, range from 0.5 : 1 to 2 : 1 , preferably 1 : 1 to 2:1. and more preferably range from approximately 1 : 1 for 1 % water contamination, approximately 1.4:1 to 1.5:1 for greater than 1 to 5% water contamination, and 1.2:1 to 1.3:1 for greater than 5 to 15% water contamination. The mixture of higher fatty acid diethanolamides is added to the water-containing petrol and is mixed in with agitation. The following examples illustrate the process of the invention and its use for the formation of stable solutions of petrol and oil.

Example 1.

In this example Caflon was used as the mixture of higher fatty acid diethanolamides.

Whereas alcohol ethoxylates have found use as the major component in treating water-containing diesel to form a clear stable homogeneous solution, tests have shown that, in contrast, water-containing petrol forms such stable solutions on the addition of Caflon alone. In order to test its effectiveness, Caflon was titrated with various concentrations of water-petrol mixtures until a clear stable solution was obtained as the end-point.

The following table and Fig 1 show the amounts of Caflon that were required to be added to water-containing petrol to produce such a clear solution.

Parts by volume of water per Parts by volume of Caflon per 100 parts by volume of petrol 100 parts by volume of petrol

1.0 1.00

2.0 3.00

3.0 4.20

4.0 5.50

5.0 7.10

6.0 7.80

7.0 8.80

8.0 10.35

9.0 11.90

10.0 12.10

11.0 13.60

12.0 15.00

13.0 15.90

14.0 17.00

15.0 18.60

The results suggest a nearly linear relationship between Caflon requirement and water content. It will be seen that the ratio of Caflon to water by volume was found to vary between 1.5: 1 at 2% water contamination of the petrol to 1.2: 1 at 10%, and greater, water contamination.

The effect of the usual components which had been found to be effective in solubilising diesel-water mixtures (i.e. Neodol 91 2.5 - alcohol ethoxylate; Texafor M6 - an polyglycol ether of a higher fatty acid; and Egme- an alcohol ethoxylate ethylene glycol monobutyl ether/ ester) were tested by carrying out further similar titrations with varying amounts of each of those additives in association with Caflon. All the other components showed a negative effect, i.e., each of the components caused an increase in the Caflon required to form clear solution (see Figure 2). There is therefore no benefit from using components other than Caflon alone as the solubilising agent for water-petrol mixtures.

Example 2.

This example shows the effect of Caflon CD218, as the complex mixture of higher fatty acid diethanolamides derived from coconut oil, in absorbing water in gasoline.

Water was added to 100ml of unleaded gasoline in 1ml increments and the amount of Caflon required to absorb the water was recorded as follows:

1. 1 ml of water required 1ml of Caflon for a clear solution,

2. 1 ml of water required a further 2ml of Caflon for a clear solution,

3. 1 ml of water required a further 1.2ml of Caflon for a clear solution, 4. 1 ml of water required a further 1.3ml of Caflon for a clear solution,

5. ] ml of water required a further 1.6ml of Caflon for a clear solution,

6. ] ml of water required a further 0.7ml of Caflon for a clear solution,

7. ] ml of water required a further 1ml of Caflon for a clear solution,

8. 1 ml of water required a further 1.55ml of Caflon for a clear solution, 9. 1 ml of water required a further 1.55ml of Caflon for a clear solution,

10. 1 ml of water required a further 0.2ml of Caflon for a clear solution,

11. ml of water required a further 1.5ml of Caflon for a clear solution.

12. ml of water ■ required a further 1.4ml of Caflon for a clear solution.

13. ml of water ■ required a further 0.9ml of Caflon for a clear solution. 14. ml of water ^■ required a further 1.1ml of Caflon for a clear solution.

15. 1ml of water ^■ required a further 1.6ml of Caflon for a clear solution.

Later Observations After 5 minutes - clear solution. After 24 hours - clear solution.

After 72 hours - clear solution. It appears from the foregoing results that there is an approximate linear relationship between the amount of water present in the unleaded gasoline and the amount of Caflon that needed to be used to solubilise the water.

Example 3.

A dynamometer test was carried out at an American University test facility to explore the effect of the introduction of water into regular unleaded gasoline (RON=87) 10% of water was solubilised into a clear stable solution in the gasoline with the addition of a Caflon as the higher fatty acid diethanolamide derived from coconut oil or its synthetic equivalent.

The results of these tests are shown in the graph of Figure 3 which plots the time taken to consume fuel (i.e. fuel consumption) against engine power output, using single cylinder research engine running at 2,000 r.p.m. From the graph it may be seen that the benefits of the introduction of water to the fuel as a solubilised additive occurred at mid- range i.e. 10% increased power output was shown in this region.

Other tests showed that leaded or super-unleaded fuel to which solubilised water had been added did not show increased efficiency over those original fuels, but was similar to them in performance. This would seem to indicate that, in terms of combustion, water as an additive in fuel is more effective without the presence of lead or other additive.

It will of course be understood that the present invention has been described above purely by way of example, and that modifications of detail can be made within the scope of this invention.

Claims

1. A process for combining petrol and water as a stable solution comprising adding an effective amount of a complex mixture of higher fatty acid diethanolamides derived from coconut oil, or from its synthetic equivalent, to the water-petrol mixture.

2. A process according to claim 1 in which a ratio by volume of the complex mixture of higher fatty acid diethanolamides to water is approximately 0.5:1 to 2:1.

3. A process according to claim 1 in which a ratio by volume of the complex mixture of higher fatty acid diethanolamides to water is approximately 0.1 :1 to 2:1.

4. A process according to claim 1 in which a ratio by volume of the complex mixture of higher fatty acid diethanolamides to water is approximately 1 :1 for 1 % by volume of water in petrol.

5. A process according to claim 1 in which a ratio by volume of the complex mixture of higher fatty acid diethanolamides to water is 1.4:1 to 1.5:1 for greater than 1% to 5% by volume of water in petrol.

6. A process according to claim 1 in which a ratio by volume of the complex mixture of higher fatty acid diethanolamides to water is 1.2:1 to 1.3:1 for greater than 5% to 15% by volume of water in petrol.

7. A process according to any of claims 1 to 5 in which complex mixture of higher fatty acid diethanolamides derived from coconut oil, or from its synthetic equivalent, is used as the sole solubilising agent

8. A process according to any of the foregoing claims in which an extender is also blended with the water- petrol mixture.

9. A process according to claim 6 in which the extender is ethanol. 7

10. A process according to claim 1, substantially as described in Example 1 or 2.

11. Complex mixtures of higher fatty acid diethanolamides derived from coconut oil when used for the production of stable solutions of water-contaminated petrol.