WO2016072864A1

WO2016072864A1 - Abrasive composition

Info

Publication number: WO2016072864A1
Application number: PCT/NZ2015/050182
Authority: WO
Inventors: Aaron Michael FINCHER
Original assignee: Sharkbite International Limited
Priority date: 2014-11-05
Filing date: 2015-11-04
Publication date: 2016-05-12

Abstract

The invention relates to an abrasive composition for abrading the surface of materials such as metals and plastics to provide a polished finish. In particular the abrasive composition includes aluminium dross (a by-product of aluminium smelting) or a refined aluminium dross.

Description

ABRASIVE COMPOSITION

TECHNICAL FIELD

BACKGROUND TO THE INVENTION

Aluminium metal may be obtained by a number of different processes from either naturally occurring ore (bauxite) or by recycling aluminium waste. What is common to all processes and all sources of aluminium is that a scum forms on the surface of the molten aluminium, wherein the scum includes a range of salts mixed with aluminium metal. The scum is known as dross and is typically removed mechanically before the molten aluminium is cast into moulds. The dross produced from primary extraction of aluminium is known as white dross, whereas the use of a salt flux during secondary extraction of aluminium leads to the production of a darker- coloured product known as black dross.

After mechanical removal of the scum layer, the dross is typically refined in a secondary extraction step to remove aluminium metal, since the aluminium metal content can be as high as 80% in white dross. The refined dross product is enriched in the residual salts and may be referred to as saltcake. Saltcake is a waste product with very few commercial uses and is typically disposed of in landfill. In some instances, saltcake is categorised as hazardous and must be handled accordingly and buried in landfill carefully to prevent leaching into

groundwater.

SUMMARY OF THE INVENTION

During the isolation of the dross from the molten aluminium metal, and during the further refinement of the dross, a significant quantity of particulate matter becomes airborne. One source of such particulate matter is a rotary kiln employed to extract aluminium metal from dross. This airborne particulate matter is typically extracted using a baghouse, which is a piece of equipment containing baffles (typically woven or felted fabric) which remove the particulate material from the air column. The particulate matter is typically bagged and disposed of, generally as landfill. It has now been found that aluminium dross or refined aluminium dross, having a small particle size, is particularly well-suited for use as a mild abrasive in an abrasive composition. In one aspect the present invention provides an abrasive composition including aluminium dross or refined aluminium dross, wherein the aluminium dross or refined aluminium dross has a maximum particle size of 1.5 mm.

In another aspect the present invention provides the use of aluminium dross or refined aluminium dross in the manufacture of an abrasive composition, wherein the aluminium dross or refined aluminium dross has a maximum particle size of 1.5 mm.

The abrasive composition is suitable for abrading a range of surfaces including chrome, steel, stainless steel, copper, silver, gold, plastic and alloys to improve, or even restore, the appearance of the material by providing a polished finish.

Without wishing to be bound by theory, it is believed that the excellent abrading ability of the present abrasive composition is provided by the combination of the components in the dross or refined dross. In particular, it is believed that the different crystalline and amorphous particles of varying sizes work together in a complementary manner to abrade the surface of the material being polished without causing unwanted damage to the material.

In another aspect the present invention provides a method of abrading a surface including applying an abrasive composition including aluminium dross or refined aluminium dross to the surface, wherein the aluminium dross or refined aluminium dross has a maximum particle size of 1.5 mm.

BRIEF DESCRIPTION OF DRAWINGS

Further aspects of the present invention will become apparent from the following description which is given by way of example only and with reference to the accompanying drawings in which:

Figure 1a is a photograph of a corroded section of copper pipe;

Figure 1 b is a photograph of the same section of copper pipe shown in Figure 1 a, a section of which has been polished using the abrasive composition of the invention. The lustre of the brass pipe has been restored by removal of the oxide coating on the copper pipe as evidenced by the amount of light reflected from the polished portion;

Figure 2a is a photograph of a tarnished alloy beer keg; Figure 2b is a photograph of the same alloy beer keg shown in Figure 2a, which has been

polished using the abrasive composition of the invention. The lustre of the alloy has been restored by removal of the oxide coating on the keg as evidenced by the amount of light reflected from the polished keg;

Figure 3a is a photograph of a tarnished and pitted chrome bumper;

Figure 3b is a photograph of the same chrome bumper shown in Figure 3a, which has been polished using the abrasive composition of the invention. The lustre of the chrome has been restored by removal of the oxide coating on the bumper as evidenced by the amount of light reflected from the polished bumper;

Figure 4a is a photograph of a tarnished silver chalice;

Figure 4b is a photograph of the same silver chalice shown in Figure 4a, which has been

polished using the abrasive composition of the invention. The lustre of the silver has been restored by removal of the oxide coating on the chalice as evidenced by the amount of light reflected from the polished chalice.

Figure 5 is a photograph of a corroded copper pipe after the action of Autosol^® (upper region) and the abrasive composition of the invention (lower region).

Figure 6 is a photograph of a corroded copper pipe after the action of Blue Magic^® (upper region) and the abrasive composition of the invention (lower region).

Figure 7 is a photograph of a corroded copper pipe after the action of Brasso^® (upper region) and the abrasive composition of the invention (lower region).

Figure 8 is a photograph of a corroded copper pipe after the action of Mothers^® (upper region) and the abrasive composition of the invention (lower region).

Figure 9 is a photograph of a damaged car panel which has been treated using a paint pen

(upper image) and subsequent partial treatment in the circled region with the abrasive composition of the present invention (lower image).

DETAILED DESCRIPTION OF THE INVENTION

The abrasive composition of the present invention may be used to improve, or even restore, the appearance of a range of materials. The material may be metals such as chrome, steel, stainless steel, aluminium, copper, silver, gold or other metal alloys, or the material may be plastic, including a resin coating applied to fibreglass or carbon fibre. The appearance of a material may have been degraded by a number of different mechanisms including removal of material from the surface (scratching, etching) or removal of deposits that have built-up on the surface of the material (metal oxide, salt deposition). Through use, the visually attractive appearance of an article may diminish as a result of the material becoming scratched. Typically such scratches are visible because incident light casts shadows, or reflects in directions that are different to the predominant direction that incident light is reflected by the surface. By abrading the edges of a scratch or even removing the scratch altogether, incident light does not cast such obvious shadows, and is not reflected in vastly different directions to the predominant direction that incident light is reflected by the surface and accordingly the scratch becomes less visible thereby improving, or even restoring, the appearance of the surface. Likewise, if a material's surface becomes etched (such as by exposure to sun or chemicals such as acid) the appearance of the surface may be improved, or even restored, by removing a portion of the material surrounding the etched portion to smooth out the overall surface of the material.

In some cases a metal oxide may build up on a metallic surface and reduce the lustre of a metal surface. By removing the oxide build up and exposing a fresh metal surface, the lustre of the material may be improved, or even restored. In other cases a salt layer may build up on a surface (such as soap scum on bathroom surfaces or salt spray on exposed surfaces). Such a salt layer can be abraded by the abrasive composition of the present invention to improve, or even restore, the appearance of the material.

In some cases the finished appearance of a plastic surface, such as head and brake light covers and/or Perspex may become frosted in appearance. The abrasive composition of the present invention may be used to restore a transparent, or substantially transparent, finish to the surface of such plastics.

The abrasive composition of the invention may also be used to sharpen a range of objects, typically by restoring a fine cutting edge. The most convenient method of sharpening a blade (such as a knife, scissors, garden implements) is to use a sharpening block or a strop of material, such as leather. A small amount of the abrasive composition can be applied to the sharpening block or strop and the blade repeatedly moved in a regular motion against the surface of the block or strop until the requisite degree of sharpening is achieved. The abrasive composition of the present invention acts simultaneously as an abrasive agent and a lubricant to allow the user to achieve a sharp edge.

Further examples of materials that the abrasive composition of the present invention has been shown to be useful on include: fibreglass (such as removing algae and the waterline stain from a fibreglass boat hull); brass (such as removing corrosion from brass metalwork); Perspex (removing frosting from car lights); plastic parts (such as removing marks from plastic vehicle bumpers, vehicle rear vision mirrors, stains on guttering, stains on vacuum cleaner, stains on a spa pool); painted parts (such as removing marks from car panels, stains from painted brick, rubber marks off the walls of a squash court); alloy; enamel (such as removing marks from whitegoods including fridge panels); graffiti (such as graffiti paint from painted brick or other hard surfaces); leather (such as removing scuff marks or paint from leather furniture); linoleum (such as removing stains from linoleum flooring including rust stains and tattoo ink stains); gold (such as jewellery); iron (such as a wheel brace); gypsum wallboard (such as removing scuff marks or paint from painted gypsum wallboard); silver (such as a silver goblet); stainless steel (such as removing stains from the housing of a heating element); tiles (such as removing soap scum and grime from a tile); and wood (such as removing pen marks from an unfinished wooden surface). In each case the appearance of the surface of the article was visibly enhanced, and typically restored to a near-original finish. Whilst a given known abrasive/polish composition might be able to restore the finish to a particular type of surface, the abrasive composition of the present invention is advantageously and surprisingly able to improve the appearance of a diverse range of surfaces without causing unintended damage to any of the surfaces.

The abrasive composition of the present invention can also be used in combination with other compositions to restore the appearance of a damaged surface. For example, a paint pen (typically colour matched) can be used to restore the colour to a scratched portion of the body work of a vehicle. The final appearance of the use of such a paint pen can be improved by the subsequent application of the abrasive composition of the present invention to blend the boundaries between the original finish of the product, and the finish provided by the paint pen as shown in Figure 9. In Figure 9 the upper photograph shows the damaged surface after application of the paint pen with the area to be subsequently treated highlighted with an arrow. In Figure 9 the lower photograph shows the damaged surface after subsequent application of the abrasive composition of the invention to a portion of the surface - encircled.

In some embodiments, the abrasive composition of the present invention provides a finish to the treated surface that displays significant resilience over time to further staining, damage, etc. In some embodiments the treated surface provides a finish which resists further damage, in some instances for up to 12 weeks or more, including up to 9 months. Without wishing to be bound by theory it is believed that the abrasive composition of the present invention can be used to provide a protective coating to the material. This protective coating may be the result of the use of certain waxy components and/or the use of fine particles of aluminium dross of refined aluminium dross which remain on the surface of the material and provide resistance to further surface damage.

As used herein, "refined dross" takes its standard meaning and refers to dross that has undergone a refinement step subsequent to mechanical removal from the molten aluminium metal during the primary extraction process. Typically the refinement step will involve further extraction of the residual aluminium metal from the dross. White dross, for example can contain up to about 80% aluminium metal. The refinement step may, for example take place in a rotary kiln, wherein aluminium dross is heated, to melt the aluminium metal, and agitated to expose fresh aluminium metal surface.

The dross or refined dross may be ground to produce a product with a maximum particle size of 1.5 mm. However, advantageously, the present inventor has discovered that aluminium dross or refined aluminium dross that may become airborne during the isolation of the dross from the molten aluminium metal, but more typically becomes airborne during the further refinement of the dross, is particularly well suited for use in the abrasive composition of the present invention.

The particle size of the aluminium dross or refined aluminium dross can be varied to produce an abrasive composition that is either harsher (larger particle size) or milder (smaller particle size) to suit the intended application. For example, in order to remove significant metal oxide deposits (eg rust) or staining it may be appropriate to use an abrasive composition having a significant quantity of large particles. On the other hand, to remove scratches from plastic surfaces or to polish fine silverware or to sharpen a blade, it may be appropriate to avoid using an abrasive composition with larger particles, and instead favour the use of an abrasive composition having much smaller particles.

The maximum particle size of the aluminium dross or refined aluminium dross present within the abrasive composition is 1.5 mm. It will be understood that the particles used in the abrasive composition will typically be irregular in shape. As used herein, "particle size" refers to the diameter of an imaginary sphere of equivalent size to the irregularly shaped particle based on equivalent volume, weight and/or surface area to the irregularly shaped particle. In preferred embodiments, the maximum particle size is 1.0 mm, such as 500 μιη, 250 μιη, 150 μιη or 100 μιη. In still further preferred embodiments the maximum particle size of the aluminium dross or refined aluminium dross is 50 pm, 45 μιη or even 5 μιη. It will be understood that the smaller the dimension of the maximum particle size, the more suitable the abrasive composition is for creating a finer finish and creating smaller residual scratches in the surface being abraded. Likewise, the larger the dimension of the maximum particle size, the more suitable the abrasive composition is for removing heavy staining or oxide deposits. Generally the particles will all be greater than about 1 pm in size and, in abrasive compositions adapted to remove heavy staining or oxide deposits (in particular), the particles are preferably greater than 5 μηι in size, such as greater than 10 μιη in size.

There are a number of techniques that can be employed to separate particles based on size, to ensure that the particles of aluminium dross or refined aluminium dross are of the desired size range. One such technique involves sieving the material. The use of two sieves, having different sieve sizes allows the separation of a desired particle size distribution having a given size range from the material being sieved. In this way it is possible to produce an aluminium dross or refined aluminium dross having a particle size distribution from 1 pm to 100 μιη, such as from 5 μηι to 45 pm. Since the particles are typically irregular in shape, a particle passing through a 45 pm sieve may actually possess a maximum dimension that exceeds 45 pm. Generally, however, such a maximum dimension will be of the order of the sieve size, such as no more than twice the sieve size.

It will be understood that the chemical composition of the aluminium dross or refined aluminium dross will depend on the source of the aluminium (from ore or recycled material) and on the processing steps involved in processing the aluminium metal. The aluminium dross or refined aluminium dross for use in the abrasive composition of the present invention will generally contain at least one of: aluminium oxide (corundum; AI₂O3); aluminium nitride (AIN); and/or magnesium aluminate (spinel; MgA C^). Preferably the aluminium dross or refined aluminium dross will contain at least two of aluminium oxide (AI2O3); aluminium nitride (AIN); and/or magnesium aluminate (MgA O^). More preferably the aluminium dross or refined aluminium dross will contain all three of aluminium oxide (AI2O3); aluminium nitride (AIN); and magnesium aluminate (MgA O^). The aluminium dross or refined aluminium dross may contain one or more of: cryolite (NasAIFe); crystobalite (crystalline S1O2); aluminium metal; sodium aluminate (NaAliiOi₇); potassium fluoride (KF); potassium chloride (sylvite; KCI); fluorite (CaF₂); quartz (Si0₂) and/or amorphous Si0₂.

Preferably the aluminium dross or refined aluminium dross will be depleted in aluminium metal. For example, preferably the amount of aluminium metal present in the aluminium dross or refined aluminium dross will be less than 20%, more preferably less than 10% and still more preferably less than 5%, such as 2%.

A representative composition of baghouse dust collected during the refinement of aluminum dross is shown in Table 1.

Table 1 : Baghouse dust

A particular baghouse dust used in the abrasive composition of the invention is shown in Table 2.

Table 2: Baghouse dust example composition

One source of baghouse dust from aluminium dross or refined aluminium dross is Taha Asia Pacific Limited (NZAS Tiwai Point, Bluff, New Zealand) and is sold as Ouvea Premix.

Further examples of baghouse dust samples used in the abrasive composition of the invention are shown in Table 3.

Table 3: Baghouse dust example compositions

nd = not detected above 0.1 % balance to 100% is amorphous. (7.8%)

Common abrasives are usually based around one mineral component, such as corundum, which is fused or cemented into or onto discs, slabs, tapes or suspended in a viscous medium to prevent settling and provide ease of application via manual or mechanical processes.

The mix of minerals used in a preferred embodiment of the abrasive composition of the present invention is advantageously substantially consistent over time as exemplified in Table 3. Without wishing to be bound by theory, it is believed that the use of a mineral component mixture as exemplified in Tables 1 , 2 and/or 3 provides a substantial advantage over previous approaches because the minerals in the mixture have a range of different hardness values - see Table 3.

In the examples shown in Table 3, approximately 61 % of the mineral component mixture has a hardness in the range 7 to 9, approximately 23% of the mineral component mixture has a hardness in the range 5 to 6.9 and approximately 8% of the mineral component mixture has a hardness in the range 2 to 3. The non-crystalline (amorphous) material is approximately 8% of the exemplified mineral component mixture and is soft - generally having a hardness value of less than 1 on the Mohs scale.

It is believed that hard angular minerals abrade contamination from a surface. The range of medium to low hardness components progressively smooth and even out any abrasion marks due to the effect of the hardest minerals. The amorphous soft components finally have a filling, polishing and restorative effect on the surfaces treated. In preferred embodiments, most, if not all of the components listed in Tables 1 , 2 and/or 3 are present in the composition of the invention. Further, in preferred embodiments of the invention each particle size range used in the composition of the invention includes most, if not all of the components listed in Tables 1 , 2 and/or 3.

It is believed that the effect of having particles with a range of hardness values as shown in Table 3 is enhanced by the use of particles of different sizes in the composition of the invention, It is believed that this combination of varying particle sizes and varying mineral component hardness values not only distinguishes preferred embodiments of the composition of the invention from previous approaches, but also provides a synergistic effect that would not have been expected.

As such, preferably the abrasive composition of the present invention includes at least two of the following three components: a mineral component having a hardness in the range of 7 to 9; a mineral component having a hardness in the range of 5 to 6.9; and/or a mineral component having a hardness in the range of 2 to 4.9.

Preferably the abrasive composition of the present invention includes three of these mineral components. In preferred embodiments at least two of the three mineral components of different hardness values are each, independently, present in an amount of at least 5% w/w of the aluminium dross or refined aluminium dross component of the abrasive composition.

Preferably the abrasive composition of the present invention includes three of these mineral components wherein each component, independently, is present in an amount of at least 5% w/w of the aluminium dross or refined aluminium dross component of the abrasive composition.

The aluminium dross or refined aluminium dross of the present invention is typically combined with a number of components in order to produce the abrasive composition of the invention. It has been found that the abrasive character of the abrasive composition of the present invention may be enhanced by providing the aluminium dross or refined aluminium dross in a paste formulation, having a viscosity that may range from near liquid to near solid. Preferably the paste is able to flow to some extent without absorbing to a significant degree into the material which may be used to apply the abrasive composition to the surface to be polished.

The aluminium dross or refined aluminium dross may be present from 1 wt% to 95wt% in the abrasive composition, however more typically the aluminium dross or refined aluminium dross will be present from 5wt% to 50wt% in the abrasive composition, such as from 10wt% to 30wt%. The amount of aluminium dross or refined aluminium dross in the composition may be varied according to how delicate or robust the material being abraded is and/or the extent of scratching or deposits on the surface of the material. Where extreme care is required, it may also be beneficial to use a relatively smaller concentration of the particles in the abrasive composition.

In order to formulate a paste composition, a range of additives may be used, including oil-based and water-based additives. The abrasive composition is typically formulated with at least one oil-based component. The oil-based component may be plant-derived or petroleum derived. The oil-based component may be naturally occurring, semi-synthetic or synthetic in character.

Examples of such oil-based components are plant oils (known generally as vegetable oils) such as canola oil (rapeseed oil), palm oil, soybean oil, sunflower oil, peanut oil, cottonseed oil, coconut oil and olive oil. A preferred plant oil is canola oil. Another example of an oil-based component is a petroleum derived oil product, such as petroleum jelly.

Without wishing to be bound by theory, it is believed that inclusion of an oil-based component within the abrasive composition of the invention assists with dispersing the particles of the aluminium dross or refined aluminium dross in order to reduce the reactivity of the particles to atmospheric water. The amount of oil may be varied within the composition to suit the intended application, and typically will be greater than 50wt% of the abrasive composition, such as greater than about 65 wt%. Typically by including a higher concentration of oil in the abrasive composition the viscosity will decrease.

The present inventor has also discovered that the presence of a wax within the abrasive composition enhances the ability of the composition to improve, or even restore, the appearance of the material being polished. The wax may be plant-derived, animal-derived or petroleum derived. Examples of such waxes are beeswax, lanolin, carnauba wax and paraffin wax. A preferred wax is carnauba wax. The amount of wax may be varied within the composition to suit the intended application.

The present inventor has also discovered that the use of aqueous ammonia within the abrasive composition is advantageous for application to some materials (such as chrome, steel, stainless steel, copper, silver and gold) but disadvantageous for application to some materials (plastic and magnesium alloy). Accordingly the present invention provides two types of formulations, with or without ammonia, which may be applied to a corresponding surface to provide an optimized polished surface. Cloudy ammonia is one source of aqueous ammonia that can be used. The cloudy ammonia may be used up to 10wt% in the abrasive composition, such as up to 5wt%, for example up to 2wt%.

In those embodiments including ammonia, the characteristic smell of ammonia may be reduced by incorporation of an acid into the composition. One such acid is citric acid.

The abrasive composition of the invention may further contain other components such as an additive agent for further increasing the polishing rate including a pH adjusting agent, a complexing agent, an etching agent and an oxidant, an additive agent that imparts hydrophilicity and dispersion effect on the surface of the hard brittle material, a preservative agent, an antifungal agent, a corrosion inhibitor, a chelating agent, a dispersant to improve the dispersibility of the aluminium dross or refined aluminium dross and a dispersion auxiliary agent to facilitate the redistribution of the aggregate of the aluminium dross or refined aluminium dross if necessary.lt should be noted that various changes and modifications to the presently preferred embodiments described herein will be apparent to those skilled in the art. Such changes and modifications may be made without departing from the spirit and scope of the invention and without diminishing its attendant advantages. It is therefore intended that such changes and modifications be included within the present invention.

Aspects of the present invention have been described by way of example only and it should be appreciated that modifications and additions may be made thereto without departing from the scope thereof.

All references, including any patents or patent applications cited in this specification are hereby incorporated by reference. No admission is made that any reference constitutes prior art. The discussion of the references states what their authors assert, and the applicants reserve the right to challenge the accuracy and pertinency of the cited documents. It will be clearly understood that, although a number of prior art publications are referred to herein, this reference does not constitute an admission that any of these documents form part of the common general knowledge in the art, in New Zealand or in any other country.

Unless the context clearly requires otherwise, throughout the description and the claims, the words "comprise", "comprising", and the like, are to be construed in an inclusive sense as opposed to an exclusive or exhaustive sense, that is to say, in the sense of "including, but not limited to".

EXAMPLES

One sample of 100 g of baghouse dust was screened to sort by particle size. The results are presented in Table 1 :

The (less than) 45 μιη fraction was used in each of formulation examples 1 to 4. Example 1 - formulation with ammonia

A mixture of carnauba wax (15 g) and canola oil (200 mL) was heated to 95-120 °C to create an homogeneous mixture. To the warm mixture was added petroleum jelly (20 g), followed by an aqueous solution of ammonia (cloudy ammonia; 5 mL), with stirring. Refined dross (30 g) having a maximum particle size of 45 μιτι was then added to the mixture before the mixture was thoroughly mixed.

Example 2 - formulation with ammonia A mixture of carnauba wax (15 g) and canola oil (200 mL) was heated to 95-120 °C to create a homogeneous mixture. To the warm mixture was added petroleum jelly (20 g), followed by refined dross (55 g) having a maximum particle size of 45 pm. To the cooled mixture was added an aqueous solution of ammonia (cloudy ammonia; 5 mL) with mixing.

Example 3 - formulation without ammonia

A mixture of carnauba wax (15 g) and canola oil (200 mL) was heated to 95-120 °C to create an homogeneous mixture. To the warm mixture was added petroleum jelly (20 g) with stirring. Refined dross (30 g) having a maximum particle size of 45 pm was then added to the mixture before the mixture was thoroughly mixed.

Example 4 - formulation without ammonia

A mixture of carnauba wax (15 g) and canola oil (200 mL) was heated to 95-120 °C to create a homogeneous mixture. To the warm mixture was added petroleum jelly (20 g), followed by refined dross (55 g) having a maximum particle size of 45 pm.

Example 5 - method of application

Approximately 3 mL of the abrasive composition of example 1 was applied to a chrome surface using a clean cloth. The clean cloth was moved in a rubbing motion and/or circular motion for approximately 30 seconds. Residual composition was removed with a clean cloth and/or with water, to provide the chrome surface having an improved lustre and having fewer visible scratches.

Example 6 - comparative examples

Abrasive composition of the invention versus Autosol^®

Two test regions of a corroded copper bar were used to compare the abrasive/polishing properties of an abrasive composition of the invention with commercially available Autosol^® metal polish - a commercially available, German made, award winning metal polish. A pea- sized quantity of each composition was applied to the respective regions of the corroded copper bar. Both compositions provided an equally good clean and polish to the metal, however the abrasive composition of the invention lasted longer, enabling cleaning around the whole bar, rather than only one side as for Autosol^®. This comparative example suggests greater longevity when using the abrasive composition of the invention.

Figure 5 is a photograph of a corroded copper pipe after the action of Autosol^® (upper region) and the abrasive composition of the invention (lower region). Abrasive composition of the invention versus Blue Magic^®

Two test regions of a corroded copper bar were used to compare the abrasive/polishing properties of an abrasive composition of the invention with commercially available Blue Magic^® metal polish - a commercially available, American made metal polish. A pea-sized quantity of each composition was applied to the respective regions of the corroded copper bar. Both compositions provided an equally good clean and polish to the metal, however the abrasive composition of the invention lasted longer, enabling cleaning around the whole bar, rather than only one side as for Blue Magic^®. This comparative example suggests greater longevity when using the abrasive composition of the invention.

Abrasive composition of the invention versus Brasso^® Two test regions of a corroded copper bar were used to compare the abrasive/polishing properties of an abrasive composition of the invention with commercially available Brasso^® metal polish - a commercially available, United Kingdom made metal polish. A pea-sized quantity of each composition was applied to the respective regions of the corroded copper bar. Significant difficulty was encountered abrading the corrosion with Brasso^®, whereas the abrasive composition of the invention was able to abrade the corrosion with relative ease. Furthermore, the abrasive composition of the invention lasted longer, enabling cleaning of a significantly larger portion of the bar. This comparative example suggests greater longevity when using the abrasive composition of the invention and furthermore suggests that the abrasive composition of the invention is a superior abrasive compared with Brasso^®. Figure 7 is a photograph of a corroded copper pipe after the action of Brasso^® (upper region) and the abrasive composition of the invention (lower region).

Abrasive composition of the invention versus Mothers^® Mag & Aluminium Polish

Two test regions of a corroded copper bar were used to compare the abrasive/polishing properties of an abrasive composition of the invention with commercially available Mothers^® metal polish - a commercially available, American made metal polish. A pea-sized quantity of each composition was applied to the respective regions of the corroded copper bar. The Mothers^® product was unable to abrade the corrosion whereas the abrasive composition of the invention was able to abrade the corrosion with relative ease. This comparative example suggests that the abrasive composition of the invention is a superior abrasive compared with Mothers^®.

Claims

The claims:

1. An abrasive composition including aluminium dross or refined aluminium dross, wherein the aluminium dross or refined aluminium dross has a maximum particle size of 1.5 mm.

2. The abrasive composition according to claim 1 wherein the aluminium dross or refined aluminium dross has a maximum particle size of 100 pm.

3. The abrasive composition according to claim 1 wherein the aluminium dross or refined aluminium dross has a maximum particle size of 45 pm.

4. The abrasive composition according to any one of claims 1 to 3 wherein the aluminium dross or refined aluminium dross includes at least one of: aluminium oxide; aluminium nitride; and/or magnesium aluminate.

5. The abrasive composition according to any one of claims 1 to 3 wherein the aluminium dross or refined aluminium dross includes at least two of: aluminium oxide; aluminium nitride; and/or magnesium aluminate.

6. The abrasive composition according to any one of claims 1 to 3 wherein the aluminium dross or refined aluminium dross includes aluminium oxide; aluminium nitride; and magnesium aluminate.

7. The abrasive composition according to any one of claims 1 to 6 wherein the aluminium dross or refined aluminium dross includes at least two of the following three components: a) a mineral component having a hardness in the range of 7 to 9; b) a mineral component having a hardness in the range of 5 to 6.9; and/or c) a mineral component having a hardness in the range of 2 to 4.9.

8. The abrasive composition according to any one of claims 1 to 6 wherein the aluminium dross or refined aluminium dross includes each of the following three components: a) a mineral component having a hardness in the range of 7 to 9; b) a mineral component having a hardness in the range of 5 to 6.9; and/or c) a mineral component having a hardness in the range of 2 to 4.9.

9. The abrasive composition according to claim 7 or claim 8 wherein each of a), b) and/or c), where present, is independently present in an amount of at least 5% w/w of the aluminium dross or refined aluminium dross component of the abrasive composition.

10. The abrasive composition according to any one of claims 1 to 9 wherein the amount of aluminium metal present in the aluminium dross or refined aluminium dross is less than 5%.

11. The abrasive composition according to any one of claims 1 to 10 including at least one component selected from: an oil-based component; a water-based component; a wax; and ammonia solution.

12. The use of aluminium dross or refined aluminium dross in the manufacture of an abrasive composition, wherein the aluminium dross or refined aluminium dross has a maximum particle size of 1.5 mm.

13. A method of manufacturing an abrasive composition including the step of mixing an oil- based component with aluminium dross or refined aluminium dross, wherein the aluminium dross or refined aluminium dross has a maximum particle size of 1.5 mm.

14. A method of abrading a surface including the step of applying an abrasive composition including aluminium dross or refined aluminium dross to the surface, wherein the aluminium dross or refined aluminium dross has a maximum particle size of 1.5 mm.

15. The method according to claim 14 further including the step of rubbing the abrasive composition repeatedly across the surface.