Here’s the simple process I followed to make 20 litres of multipurpose liquid soap.

Step 1: Add Water

Start by pouring the 20 litres of water you want to use directly into the washing machine.

Step 2: Add Nitrosol (Thickener)

The first chemical to go in is nitrosol, which acts as the thickener. Once added, let the machine run so it mixes properly with the water.

Step 3: Add Sulphonic Acid

Next, add sulphonic acid (gel form). Allow the washing machine to mix everything well before adding the next ingredient.

Step 4: Add Soda Ash

Since soda ash is a powder, dissolve it in a separate bucket of water first.

Important rule: always add water before adding the chemical when diluting.

Once fully dissolved, pour it into the main mixture.

Step 5: Add STPP

The next ingredient is STPP (Sodium Tripolyphosphate). This one doesn’t require dilution, so you can add it directly.

Step 6: Add Caustic Soda

Just like soda ash, caustic soda must be diluted first in a separate bucket before adding it to the mixture.

Step 7: Add SLES

Then add SLES, which helps with lathering and cleaning power.

Step 8: Add Texapon

Next is Texapon, which boosts foam and improves the soap’s washing ability.

At this stage, make sure the washing machine keeps running so the ingredients mix thoroughly.

Step 9: Add Preservative (Optional)

You can add a preservative to extend the shelf life of the soap, but it’s optional.

Step 10: Add Fragrance and Colour

Finally, add your fragrance (I used lemon).

Then add colourant, which should also be diluted first before pouring into the mixture. Colours can vary depending on your preference.

Final Mixing

After adding everything, let the washing machine run for about 9 minutes so the mixture blends properly.

Then allow the soap to sit for several hours so it thickens. You don’t necessarily have to wait a full 24 hours.

By the time it settles, you’ll have 20 litres of multipurpose liquid soap ready to package or use.