Denatured alcohol has a plethora of uses for home and industry. Used frequently as a solvent, denatured alcohol is also helpful in household cleaning because its grease-cutting properties surpass ordinary soaps and detergents. It's also used as rubbing alcohol and as fuel for camp stoves. All denatured alcohols—such as ethanol, methanol, ethyl acetate and rubbing alcohol—are classified as hazardous waste by the Resource Conversation Recovery Act (RCRA) because of their highly flammable properties. Great care must be taken in their disposal.

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Many spot cleaners and rubbing alcohols are highly flammable and are considered hazardous waste.
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Denatured alcohol is highly flammable, so keep it away from fire and heat.

Keep the preparation area free of flames, sparks or other heat sources. This includes gas pilot lights and tobacco smoke. Make your workspace well-ventilated.

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A bucketful of sand is a safe agent to soak up denatured alcohol.

Place a leak-proof container on the floor. It must be large enough to contain the amount of denatured alcohol on hand, plus enough sand, dirt or plain cat litter to absorb the liquid. Many denatured alcohol products include ethanol. Ethanol is classified by Columbia University as "a flammable liquid ... forbidden from entering the public sewer." Thus, even a small amount must be disposed of properly.

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Unlike water, denatured alcohol is hazardous waste. Pour it carefully.

Pour the denatured alcohol into the container. Protect your eyes and hands, and do not splash the alcohol onto your skin or your clothes.

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A glass jar is a usable vessel for denatured alcohol. Be sure its lid is tightly sealed.

Transfer the absorbed alcohol and sand into a glass or metal container. Seal the container's lid, and keep it tight. If the container leaks or seems compromised, replace it at once.

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Make obvious what is in the disposal container; label it clearly.

Label the container. Use labeling material, such as masking tape or sticker paper, to identify the denatured alcohol inside the container. Write the product's name if you don't know the exact chemical content of the solution.

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Don't leave your denatured alcohol waste for the garbage man. Take it to an approved disposal site.

Contact your area waste disposal service, such as the city dump, and learn where and when hazardous waste materials may be brought for disposal. Store the sealed waste container in a cool, dry place until it can be taken for disposal.