Claims:Claims:

1. Diesel exhaust fluid (10) for use in exhaust gas treatment in automotive vehicles, the diesel exhaust fluid (10) mixed with a colorant.

2. The diesel exhaust fluid (10) as claimed in Claim 1, wherein the colorant is brilliant blue.

3. The diesel exhaust fluid (10) as claimed in Claim 1, wherein the colorant is indigo carmine.

4. The diesel exhaust fluid (10) as claimed in Claim 2, wherein the concentration of brilliant blue in the diesel exhaust fluid is 5 ppm.

5. The diesel exhaust fluid (10) as claimed in Claim 3, wherein the concentration of indigo carmine in the diesel exhaust fluid is 5 ppm.
, Description:
Complete Specification:

The following specification describes and ascertains the nature of this invention and the manner in which it is to be performed.
Field of the invention
[0001] This invention relates to the field of diesel exhaust fluid for use in exhaust gas treatment in automotive vehicles.

Background of the invention
[0002] Adulteration of diesel exhaust fluid (DEF) is very rampant in the market nowadays. Adulteration of DEF can be done by adding water to the original DEF which cannot be detected easily, as the DEF is colorless like water. Water that is added to original DEF is usually contaminated water having high concentration of impurities, which can be physical or chemical. The source of water can be from the tap or a borewell. Physical impurities can clog the DEF filter easily thereby reducing the life of the filter etc. Chemical impurities in adulterated DEF can deteriorate the quality of the catalyst in the exhaust, thereby quickly deteriorating the effectiveness of exhaust gas treatment. Hence, there is a need for a way to detect adulteration of diesel exhaust fluid that is sold commercially. US2010200107 discloses a storage and dispensing system for diesel exhaust fluid.

Brief description of the accompanying drawing

[0003] Figure 1 illustrates a storage arrangement for diesel exhaust fluid in vehicles.

Detailed description of the embodiments
[0004] Figure 1 generally illustrates a storage arrangement or reservoir 5 for storing diesel exhaust fluid (DEF) 10 in a vehicle. Diesel exhaust fluid is also referred to as Adblue. The diesel exhaust fluid 10 is injected into an exhaust pipeline 15 by way of an injector 20.

[0005] The diesel exhaust fluid 10 in this invention is mixed with a colorant. The diesel exhaust fluid 10, as described earlier is used for exhaust gas treatment in automotive vehicles. The colorant provides a color to the DEF 10. The preferred color of the colorant is blue, though colorants of other colors can also be used. Adding the blue colorant to DEF 10 imparts a blue tinge to the DEF 10 that is sold commercially.

[0006] In one embodiment, the colorant can be brilliant blue or brilliant blue FCF. Brilliant blue FCF is an organic compound classified as a triarylmethane dye and a blue azo dye, reflecting its chemical structure. Brilliant blue FCF has a color index of 42090. Color index is commonly understood in this technical art. The chemical formula of brilliant blue FCF is C37H34N2Na2O9S3.

[0007] In another embodiment, the colorant can be indigo carmine. Indigo carmine is an organic salt derived from indigo by sulfonation. The chemical formula of indigo carmine is C16H8N2Na2O8S2.

[0008] Generally the concentration of the colorant, brilliant blue in DEF can be 5 ppm. The concentration of indigo carmine in DEF can be 5 ppm. Alternatively, the concentration of brilliant blue can be 4 ppm also. Alternatively, the concentration of indigo carmine can be 4 ppm also.

[0009] Standardizing a specific concentration of the colorant imparts a fixed blue tinge or blue color to the DEF 10 which can be measured and verified by spectrophotometry. If the above mentioned DEF 10 mixed with the colorant is adulterated by using water or urea solution, then DEF 10 becomes diluted which is reflected in the color of the DEF 10. Thereby, it is easily identifiable that the DEF 10 has been adulterated. Even if the dilution in the color is not identifiable by the naked eye, the dilution in color can be identified by spectrophotometric techniques. Thereby, the DEF 10 mixed with the colorant can reduce cases of adulteration by mixing with water or urea solution to a significant extent. This is the benefit of adding colorants to DEF 10.

[0010] Both brilliant blue and indigo carmine are organic compounds and it can get consumed or combusted alongside in the urea reactions.

[0011] The addition of brilliant blue and indigo carmine in DEF 10 is done during the last stages of preparation of DEF 10.

[0012] The other colors of the colorant can be red or orange or pink, which can be provided by dyes or colorants of the respective colors.

[0013] It should be understood that embodiments explained in the description above are only illustrative and do not limit the scope of this invention in terms of the type of injector used and the material used for sealing washer. Many such embodiments and other modifications and changes in the embodiment explained in the description are envisaged. The scope of the invention is only limited by the scope of the claims.