ENHANCED FUELS, METHODS OF PRODUCING ENHANCED FUELS, AND ADDITIVES FOR MITIGATING CORRISION

Abstract

A fuel for use in internal combustion engines, wherein the fuel includes a mixture of at least one alcohol, water, urea and/or Ammonium Nitrate. The water is included in a quantity which renders the Ammonium Nitrate and/or urea dissolved in the at least one alcohol. The at least one alcohol is methanol included in a concentration having a range of 90-97 weight %. The Ammonium Nitrate is included in a concentration having a range of 0.5-10 weight %; more optionally, the Ammonium Nitrate is included in a concentration having a range of 1-5 weight %. Further, the urea is included in a concentration having a range of 1-10 weight %.

Claims

1-7. (canceled)

8. A fuel for use in internal combustion engines, wherein the fuel includes a mixture of: (i) at least one alcohol, wherein the at least one alcohol includes methanol; (ii) Ammonium Nitrate in a concentration having a range of 0.5-10 weight %; (iii) urea in a concentration having a range of 1-10 weight %; and (iv) water to dissolve the Ammonium Nitrate and Urea in the at least one alcohol.

9. The fuel as claimed in claim 8, wherein the Ammonium Nitrate is included in a concentration having a range of 1-5 weight %.

10. A method of producing a fuel, wherein the method includes: (i) Mixing at least one alcohol, Ammonium Nitrate in a concentration having a range of 0.5-10 weight % and urea in a concentration having a range of 1-10 weight %, wherein the at least one alcohol is methanol; and (ii) During mixing in (i), adding water so that the Ammonium Nitrate and urea becomes dissolvable in the at least one alcohol.

11. The method as claimed in claim 10, wherein the Ammonium Nitrate is included in a concentration having a range of 1-5 weight %.

12. A fuel additive including a mixture of Ammonium Nitrate, urea and water, for use in at least one alcohol-based fuel, wherein the at least one alcohol is methanol included in a concentration having a range of 90-97 weight %, wherein the urea is included in a concentration having a range of 1-10 weight %, wherein the Ammonium Nitrate is included in a concentration having a range of 0.5-10 weight %, and wherein the water is included in a quantity which renders the Ammonium Nitrate and urea dissolved in the at least one alcohol.

Description

DESCRIPTION OF THE DIAGRAMS

[0034] Embodiments of the present invention will now be described, by way of example only, with reference to the following diagrams wherein:

[0035] FIGS. 1 and 2 are graphical illustration of enhanced fuel pursuant to the present disclosure.

DESCRIPTION OF EMBODIMENTS OF THE DISCLOSURE

[0036] In recent years, current environmental laws and society pressure have placed less emphasis on economics of fuels, and more on environmental gains.

[0037] Nevertheless, an additive that costs less, and makes an overall combustion process in internal combustion engines more efficient will increase economic benefits, which associated to intrinsic environmental gains, makes alcohol once more an attractive alternative to diesel fuel from a commercial perspective.

[0038] In overview, the present disclosure is concerned with an enhanced fuel which is based upon an alcohol, for example ethanol and/or methanol, which is economical to produce, and which can be used as a diesel fuel substitute, with only minor changes being necessary to an internal combustion diesel fuel engine.

[0039] As is well known in the art, fuel compositions typified by methanol and/or alcohols must possess low corrosion activity; and this is usually effected by the addition of various corrosion inhibition systems. Corrosion inhibitors intended for use in fuel systems must be effective in very small quantities so as to avoid adverse effects and so as to minimize costs.

[0040] In the present disclosure, there is proposed a fuel additive and a combination of fuel additives particularly characterized by corrosion inhibition, ease of use and cost-effectiveness.

[0041] In an embodiment of the present disclosure, in an additive composition, urea is employed as a corrosion inhibitor for methanol or any other alcohol, together with AN as an ignition enhancer.

Enhanced fuel=Methanol+water+AN+ureaEq. 1

Enhanced fuel=Methanol+water+ureaEq. 2

[0042] Where water, urea and AN; or water and urea form the fuel additives. Urea provides the resistance to corrosion and AN provides ignition improvement/cetane enhancement as described supra. Corrosion resistance is provided by decomposition of urea into ammonia and by-product(s). Ammonia-gas is the main active component for the anti-corrosive action in the exhaust system of vehicles

[0043] Where,

Methanol+3/2O.sub.2=>CO.sub.2+2H.sub.2O

Urea+H.sub.2O=>2NH.sub.3(gas)+CO.sub.2

[0044] Typically, the carbon dioxide generated in the two reactions depicted above is corrosive. Carbon dioxide reacts with water as follows:

CO.sub.2+H.sub.2O=>HCO.sup.3+H+

[0045] As the concentration of CO.sub.2 increases, so does the concentration of the H.sub.+ ion. This ion then react with Fe in metals: Fe+2H+=>2H (atom)+Fe.sup.2+ As corrosion proceeds, the ferrous ions produced react with the bicarbonate ions to form ferrous carbonate which precipitated as a scale.

[0046] However, in this embodiment the ammonia released, mitigates the corrosive effect of carbon dioxide. Although ammonia is corrosive by itself the formed ammonium carbonate and ammonium bicarbonates retard and inhibit corrosion. The possible reactions being

CO.sub.2+NH.sub.3+H.sub.2O.fwdarw.(NH.sub.4)HCO.sub.3

CO.sub.2+NH.sub.3+H.sub.2O.fwdarw.(NH.sub.4).sub.2CO.sub.3

[0047] Where the carbon dioxide is captured by the ammonia to form the carbonates and the bicarbonates of ammonia.

[0048] Pursuant to embodiments of the present disclosure, Ammonium nitrate (AN) has a significant potential as a cetane enhancer for alcohols, such as methanol. The cetane enhancement capability effectively allows AN to be used as an ignition improver for such alcohol fuels. AN is not very soluble in methanol for example, but both methanol and AN are soluble in water. Therefore, there is disclosed a fuel including a mixture of an alcohol, for example ethanol and/or methanol, AN, urea and water (Eq. 1) Also, disclosed is a fuel including a mixture of an alcohol, for example ethanol and/or methanol, urea and water (Eq. 2). Such fuels are beneficially manufactured from a method including: [0049] (i) Mixing methanol, AN and urea to the desired concentration, for example in a range of 1-10 weight % AN relative to methanol and for example in a range of 1-10 weight % urea relative to methanol, wherein the is methanol included in a concentration having a range of 90-97 weight %, more specifically, 95 weight %; and [0050] (ii) During mixing in (i), adding enough water so that AN and urea (based on Eq. 1); or urea (based on Eq. 2) becomes dissolvable in the methanol water mix.

[0051] In step (i) of the method, the range in which AN needs to be added is defined by a ratio N/C (namely, Nitrogen to Carbon), wherein Nitrogen atoms come from the AN additive and Carbon atoms, mostly, comes from the fuel, for example methanol.

[0052] In step (ii) of the method, water needs to be added to an extent that solubilises the required amount of AN and urea, or just urea. The ranges provided are preferentially by volume.

[0053] The mixture of water, methanol, AN and urea (Eq. 1) and the mixture of water, methanol and urea (Eq. 2) are of advantage in that it can be easily stored over a long-term period without separating out into individual components parts, and does not form an emulsion and does not need to be emulsified. The enhanced fuels pursuant to Eqs.1 and 2 only contain fully soluble compounds and, thus, are considered to be more stable and more reliable in operating conditions. Further, the enhanced fuels pursuant to Eqs. 1 and 2 are considerably cheaper than known diesel fuel substitutes based on methanol, for example employing Avocet, and also is very clean when burnt in an internal combustion engine, for example very low soot production and low NOx production.

[0054] Methanol can be generated from a variety of sources, for example from fermenting biological waste, form processing wood by-products, from fossil fuel reserves, from coal, from coal liquefaction, from hydrates and so forth; mutatis mutandis ethanol is similarly derivable.

[0055] Embodiments of the present disclosure are concerned with an introduction of a new additive which increases the efficiency of a given fuel, for example methanol-based fuel, by acting as a cetane enhancer and/or anti-corrosion agent. The additives can be water, urea and AN; or water and urea. The new additive provides at least one of following benefits: [0056] (a) The new additive allows methanol to act a direct replacement for diesel fuel; [0057] (b) The new additive in solution Is non-explosive, and thus less hazardous in than, for example, octyl nitrate; [0058] (c) The new additive has a potential for application in petrol engines; and [0059] (d) The new additive could reduce corrosion by methanol.

[0060] Cetane is a measure of an ignition quality of a diesel fuel. The higher the cetane measure of a given diesel fuel, the easier it is to start a standard (direct injection) diesel engine using the given diesel fuel. The cetane measure is defined by a percentage, by volume, of cetane, with a chemical name hexadecane, in a combustion mixture, containing cetane and 1-methylnaphthalene, whose ignition characteristics match those of a given diesel fuel being tested. Comparisons with other additives and fuels can be made by way of equivalent cetane measure, for example as employed when describing embodiments of the present disclosure.

[0061] Benefits of the enhanced fuels in Eqs. (1 and 2) include: [0062] (a) The method allows Ammonium Nitrate to be used as an ignition improver to methanol or similar alcohols, in turn allowing the fuel to be used in existing diesel engines with minimum modifications; [0063] (b) The addition of water keeps an engine, burning the fuel, cool (due to a high latent heat of water), thereby decreasing a need for cooling systems, thus making the vehicle more energy efficient; [0064] (c) Lower particulate emission from engines burning the enhanced fuel, namely lower particulate emission than achievable by employing other methods, for example sing exhaust filters, using Adblue spraying in exhaust systems and so forth; [0065] (d) Environmentally friendly, since the N-groups in AN are released as N.sub.2 gas at the end of a burn cycle in a combustion engine; [0066] (e) The enhanced fuel results in a significant reduction in cost in comparison to PEG-dinitrate-based additives, namely AN cost approximately less than 1/20th of PEG-based additives; and [0067] (f) Cooler engine operation consequent upon the introduction of water results in lower NOx formation. Since NOx is the precursor of tropospheric ozone pollution, the reduction in NOx constitutes a significant environmental benefit [0068] (g) The enhanced fuel results in mitigation of corrosion by methanol and constitutes a significant improvement in the fuel quality.

[0069] In an example, systems and methods are disclosed for the use of an aqueous solution of ammonium nitrate (AN) as an ignition improver and urea as a corrosion inhibitor, directly injected into the engine cylinder. In another example, systems and methods are disclosed for the injection of urea into methanol for corrosion inhibition.

[0070] Theoretically, systems based on Eqs. (1 and 2) could allow the formation of a small amount of formic acid which is also corrosive. However, formic acid is unlikely to form due to the reaction:

Formic acid+1/2O.sub.2=>CO.sub.2+H.sub.2O

[0071] Where formic acid breaks down into carbon dioxide and water

[0072] It is noted that as used herein, the term fuel, can be any substance suitable for use as a diesel fuel. According to another aspect, methanol plus lubricity additive can be used directly in spark-ignited petrol engines, so providing a universal fuel.

[0073] Modifications to embodiments of the invention described in the foregoing are possible without departing from the scope of the invention as defined by the accompanying claims. Expressions such as including, comprising, incorporating, consisting of, have, is used to describe and claim the present invention are intended to be construed in a non-exclusive manner, namely allowing for items, components or elements not explicitly described also to be present. Reference to the singular is also to be construed to relate to the plural. Numerals included within parentheses in the accompanying claims are intended to assist understanding of the claims and should not be construed in any way to limit subject matter claimed by these claims.