GB2316950A

GB2316950A - Firelighter comprising a fatty acid and a polymer

Info

Publication number: GB2316950A
Application number: GB9718118A
Authority: GB
Inventors: Eric Dennis Barford; Bruce Michael Harrison
Original assignee: Advanced Natural Fuels Ltd
Current assignee: Advanced Natural Fuels Ltd
Priority date: 1996-08-27
Filing date: 1997-08-27
Publication date: 1998-03-11
Anticipated expiration: 2017-08-27
Also published as: GB9718118D0; GB9617827D0; GB2316950B

Abstract

A firelighter having good flame properties and low odour comprises a fatty acid and/or fatty acid ester component, such as stearine structured with a synthetic polymeric substance such as urea-formaldehyde resin.

Description

FireliPhter The present application relates to a firelighter. In particular, it relates to a firelighter structured by a synthetic polymer, such as a urea-formaldehyde resin structured firelighter.

Urea-formaldehyde structured firelighters and methods for producing them are well known. These firelighters incorporate a petroleum derived fuel, usually kerosene, which gives a long lasting strong flame. The firelighters typically have a bad odour before burning and a sooty, dirty flame.

The present inventors have realised that kersosene may be replaced by fatty acids and/or fatty acid esters.

Accordingly, the present invention provides a firelighter comprising a fatty acid and/or fatty acid ester component structured with a synthetic polymeric substance.

The fatty acid and/or fatty acid ester component may comprise a fatty acid, a fatty acid ester, or a mixture of fatty acid and fatty acid ester. The component may comprise a mixture of different fatty acids, fatty acid esters or mixture of fatty acid esters and fatty acids.

Of particular interest are the liquid or solid fatty acids and esters having eight carbon atoms or more.

Of particular interest are higher fatty acids and esters, including C12-C22, preferably C14-C18, most preferably, C16/C18 fatty acids and esters thereof. The alkyl component in the esters is preferably a short chain, for example C1-C4 alkyl moiety.

The fatty acid/fatty acid ester composition may comprise additional minor ingredients such as olefin acids, polyunsaturated acids etc. A particularly preferred composition comprises a mixture of C16/C18 fatty acids. This is commonly referred to as stearine, in fact comprising a mixture of stearic and palmitic acids.

Preferably, the fatty acid/fatty acid ester component is derived from natural sources, such as palm oil, coconut oil, linseed oil, rapeseed oil, palm kernel oil or rice bran oil.

Particularly preferred is palm stearine, which comprises a mixture of stearic and palmitic acid.

Stearine has a markedly higher flashpoint than kerosene ( 170-1 90"C), burns with a much cleaner flame and is essentially odourless.

The synthetic polymeric structurant may be of any suitable form. Preferably it comprises a structurant that can be mixed in liquid form with the fatty acid/ester component and polyermised. Particularly preferred is urea-formaldehyde resin.

Other additives, such as perfumes, colorants, stabilisers etc may be added as is well known in the art in suitable quantities.

Preferably, the firelighter comprises 60-90% by weight fatty acid/fatty acid ester component, preferably 75-85% by weight, 2-20, preferably 5-15, particularly 6-8% by weight synthetic polymeric material and 10-20, preferably 12-15% by water.

Other combustible components may be included such as paraffin wax, but are not preferred.

The present invention further provides a method of manufacturing a firelighter comprising mixing a fatty acid and/or fatty acid ester component in liquid form with a liquid polymerisible synthetic resin and polymerising the synthetic resin and forming a solid firelighter.

Preferably. the resin is solidified by heating and/or by catalyst. For example, a urea-formaldehyde resin may be hardened by addition of phosphoric acid.

in a preferred process, the synthetic resin is dissolved in water and then mixed with approximately 0. 1% by weight of an emulsifying agent, for example alkyl benzene sulphonate. Nonyl benzene sulphonate is preferably used. This mixture may be then mixed with the fatty acid/fatty acid ester component slowly to obtain a stable oil in water emulsion with the fatty acid/fatty acid ester as the internal phase and the aqueous solution of polymer resin as the continuous phase.

In order to form a stable emulsion the fatty acid/fatty acid ester component is preferably added slowly with agitation to the aqueous solution of polymeric resin.

This emulsion may be stored before use.

When required, the emulsion is treated to polymerise the resin, for example by heating or by addition of acid, for example one molar phosphoric acid. The mixture is delivered while still liquid to a mould or moulds to solidify. The solidified mass may be cast into the form of firelighters or it may be cast into a larger form which can be subsequently cut or moulded to form firelighters or firelighter blocks.

The fatty acid/fatty acid ester is preferably liquid when mixed with the other components. In general, fatty acid esters of appropriate molecular weight are liquid at ambient temperature and do not need to be melted. However, fatty acids such as stearic acid are typically solid at ambient temperature.

Accordingly, the mixing is preferably carried out at a temperature in excess of the melting point of the fatty acid/fatty acid ester.

Where urea-formaldehyde resin is used it is polymerised by mixing the emulsion, preferably in an in-line mixer, with one molar dilute phosphoric acid in a quantity of 0.1-1, preferably 0.25-0.5 weight %.

Some forms of fatty acids will have sufficient pKa to polymerise a resin themselves without addition of further acid. in this case, is preferred that the process comprises a plurality of mixing stages, at least one of which comprises addition of fatty acid to the polymeric resin solution. Further mineral acid may optionally be added at suitable stages in order to speed up the reaction if desired. Where the polymerisation reaction is carried out at elevated temperature, the temperature may further accelerate the polymerisation reaction. For example, if the fatty acid/fatty acid ester phase contains a high proportion of free fatty acids, or consists only of fatty acids, the combination of high working temperature and the acidity of the fatty acids will be generally adequate to induce polymerisation of the resin without addition of catalyst.

Under these conditions, the emusion cannot be stored but must be prepared as required for use.

It may be beneficial to slow the polymerisation reaction by reducing the acidity.

The addition of an organic base may be used, such as hexamine, preferably added at a level of 0.5 to 5% by weight.

The combustion properties of the firelighter may improve if the firelighter is aged for at least one week before use, as the structurant sets.

In a preferred embodiment, palm stearine is used. This is solid a room temperature.

Preferably the palm stearine has a iodine value less than about 100, preferably about 45. Palm stearine may be melted and supercooled so that it exists in liquid form at a temperature of 30-40 C.

Preferably, however, the palm stearine is melted and mixed with an aqueous solution of polymeric resin in an apparatus which is maintained at a temperature above the melting point of palm stearine.

The present invention will be further described by way of example only.

Example 1 40g of a 1 wt% solution of sodium nonyl benzene sulphonate in water are mixed thoroughly with 47g of urea-formaldehyde polymer solution (70% by weight in water) obtainable under the trade name AEROLITE UL 1771 (Trade mark) from DYNOCHEM of Duxford, Cambridge, UK and 4g of a solution consisting of 12% ammonium chloride and 10% by weight hexamine in water. After this mixture is complete, 310g of palm stearineax (obtainable from Woodland & Co. of Ware, UK) is added at a temperature in excess of 57"C. The palm stearine wax is added in small doses accompanied by vigorous mixing. The resulting mixture is poured immediately into moulds. When cooled, solidified firelighter compositions having good odour are produced.

Example 2 A mixture prepared comprising the following ingredients: 30 g of 1% by weight solution of sodium nonyl benzene sulphonate, 30 g of water, 30 g of urea - formaldehyde polymer solution (70% by weight in water) obtainable under the trade mark AEROLITE UL 1771.

To this mixture, 210 g of melted palm stearine wax obtainable from Woodland & Co. of Ware, UK are added in small portions with vigorous stirring. The mixture is immediately poured into moulds.

The moulded composition cured sufficiently to be handled in less than an hour.

The solidified firelighters were stored for a period of one week to allow the resin to cure completely.

Firelighter compositions having good odour and burning properties were obtained.

Claims

CLAIMS:

1. A firelighter comprising a fatty acid and/or fatty acid ester component structured with a synthetic polymeric substance.

2. The firelighter according to claim 1, wherein the fatty acid and/or fatty acid ester comprises at least one liquid or solid fatty acid or fatty acid ester having eight carbon atoms in the molecule or more.

3. A firelighter according to claim 1 or 2, comprising at least one C12-C22 fatty acid or fatty acid ester.

4. A firelighter according to any preceeding claim, comprising palm stearine.

5. A firelighter according to any preceeding claim, wherein the synthetic polymeric substance comprises a urea-formaldehyde resin.

6. A method of manufacturing a firelighter comprising mixing a fatty acid and/or fatty acid ester component in liquid form with a liquid polymerisable synthetic resin and polymerising the synthetic resin and forming a solid firelighter.

7. A method according to claim 6, wherein the synthetic resin is polymerised by heating and/or by the use of catalyst.

8. A method accoriding to claim 7, wherein the catalyst comprises phosphoric acid solution.

9. A method according to any of claims 6-8, wherein the synthetic resin is dissolved in water and mixed with approximately 0.1% by weight of an emulsifying agent, the mixture being then mixed with the fatty acid/fatty acid ester component to obtain a stable oil in water emulsion.