Recycle Your Old Soap





Introduction: Recycle Your Old Soap

About: I enjoy visiting the dump to look at, and take, all the free stuff people throw away. It's a lot of fun. I like Xbox live cus it's the best.

Have small insignificant pieces of soap in your bathrooms, kitchens, or workplaces? Follow this instructable and you can recycle your soap!

Step 1: Choppy Choppy!

What you'll need:

1. The ugly soap.
2. A styrofoam cup, or other microwave safe container you'd like.
3. A microwave.
4. Knife or the likes.
5. Disposable cutting surface, Paperplate!

Collect all of your little pieces of soap. These are usually the ones that have become small, balled up, dirty, or disfugured from too much use. Don't get me wrong, hand washing is a good thing. :)

Gather all of the mutant soaps and put them on a paperplate. Get your knife (I just used a butterknife) and cut all of the soap into tiny pieces. The smaller the better usually.

Step 2: Soap Formation.

After chopping up all those little soaps, mix up the newly formed pieces and place in a styrofoam cup. Push the soap pieces into the cup so that they are snug, and then fill the cup with water so it comes to the same level as the top of the soap.

Step 3: Microwave It.

Get your cup o' soap and put it in the microwave on something to collect anything that may fly out during the soap transformation (like a napkin).

Put your microwave on for maybe 30 seconds.


After you've microwaved the soap until some of the water rises out of the cup, remove it from the microwave and set it somewhere. You can use this time to find something that has the same diameter as the middle of the cup, and a sandwhich bag or ziploc bag. Put the object in the bag, (I used a vitamin bottle) and push it into the soap to make it more dense.

Step 4: Finishing.

Now, leave the water in the cup at the same level as the soap, and place the cup somewhere to sit for about a week. A good place to put it is somewhere around your sink, so incase it spills, it spills into the sink. After about a week, the water in the cup should evaporate, leaving you with a new bar of soap.

I hope you enjoyed this instructable!

This is an Idea I had that could maybe get small kids to wash their hands more. When you're in the begining stages of putting the soap pieces in the cup, maybe put a couple of quarters in the middle of it, when it solidifies there will be money in the middle, a reward for throughly washing hands. Little kids always love shiny money. :)

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What can I use in place of microwave?



I was looking for such a method because I'm in a waste-reducing process. Why would you want to recycle your soap otherwise ?
But lots of disposable stuff are being used here. Do it smart, use washable ustensils !

Soap (supposedly) melts at a quite low temperature - well below the boiling point of water. Significantly overheating it may easily cause it to change its chemical structure. It's probably safer to melt it in a double boiler - with no water at all, whatever water you add you'll need to evaporate later on, or else your soap will be extremely soft. You don't even need to have the water boiling, it's enough to just keep it very hot, at about 55-60 degrees Celsius/120 - 125 Fahrenheit.

You can use a plastic cup (one left over from yogurt, or the cut out bottom of a plastic bottle, for example) placed in a pan filled with water, and boil the water. This should be safer (for the soap) than microwaving. Plus, plastic bottles and yogurt cups are smooth, unlike styrofoam cups, leaving the re-melted soap bar with a smoother surface.

Last time I did this, the plastic cup idea did not yet occur to me, so I just placed all soap pieces in a plastic bag and tied it up with as little air inside as possible, then boiled it in water for about 15 minutes, then left it to cool in a tiny bowl and peeled off the bag. The recycled soap bar came out nice and smooth, although a little oddly shaped. Only, a plastic bag is too easy to puncture and difficult to close up so that no water gets in while air still can get out.

I can't be sure, but you possibly overheated it and changed the soap's chemical structure.

Hello sir/madam.

Thanks for the good idea on recycling soap.

i tried to recycle my bar soap which was made by palm oil only and it was good soap but the problem the bar soap gets broken , i made about 100 bars of soap they all got broke in halves.

Can you help me may be imissed something when I was mixing.

1 reply

You may need to adjust your recipe and dry it longer before you use it.

another way you could do this to make it a little nicer looking is boiling water, putting the soap pieces in a heat resistant bowl smaller than the pot and put it in the water so that the bowl is floating. Add about two teaspoons of the boiling water into the bowl. Then wait until the pieces are pretty mushy. Take out the bowl and carefully mush the soap pieces together. Then scoop out the soap and mold it into whatever shape you want (on a piece of tin foil). Lastly put it into the refridgerator until its hard.

I can`t believe how easy this was, I have arthritis in my hands and once a bar of soap is worn down below half I really struggle to hold it and was wasting so much, so after I got my niece to chop up the old bits we got to work and made over ten bars which would have cost me about £8, i,m over the moon

Never mind I figured it out.

Great! I had 2 soaps that had lost their scent, so I did this, added cochineal for colour and essential Lemon Thyme and Lavender oils, and have very nice soap evaporating on the kitchen window sill.

I did this to reuse some goats milk soap scraps, but it didn't work. I think it might be because it wasn't a commercial soap. It was made with several types of organic oils like coconut, anise, etc. But I just took the soapy water and put it in a foaming hand soap dispenser and it works well for that. Like a nice concentrated moisturising soap.

I think this is an awesome ideal as a Science project to make in Childcare,, ages 4-5 being supervised. awesome

...NOW...if someone could just do an Instructable on "How to make a Soap Mold/Press" ..we'd be in Heaven !!!!!!!

I have tonnes of these little scraps in the corners of the shower. Brilliant! I did what you've suggested here, but to make the bits smaller, I added the chunks to my old blender with about an equal volume of water and blended/pulsed for less than a minute. I then heated the resultant creamy paste in a double pot system (soap pot inside larger pot with boiling water). Then scooped the gunk into a 1liter cut-off milk carton. We shall see.

I like this instructable. But if you're doing the add quarters thing, bear in mind that coins are absolutely filthy (unless, I guess, it's brand spanking new out of a roll). Putting something filthy in the middle of my bar of soap grosses me out.

As for the money issue in the microwave, don't add it till AFTER it's cooked. I just did this (no money) and the soap bubbles up and is very soft. You have to push it down with a spoon to shape it. At THAT point, add whatever you'd want to the pending bar ...

With regard to quarters causing sparks, this would not be a problem as quarters dont have jagged edges to spark from. See the Mythbusters episode regarding metal in microwaves.

Just a comment on the money in the soap, this is a reaaaallllyyy bad idea if youre gunna be using a microwave. I predict sparking, exploding, boiling microwave soap flying everywhere if you attempt this.

Thanks, I love the idea and easy peasey instructions!