What is the difference between making hard soap and liquid soap? Both sodium and potassium are very useful chemical elements because they form a wide … Is the kind of Lye you use the only difference, or does the recipe change if your making liquid soap? When sodium hydroxide is used, the chemical reaction (sap) produces a solid bar of soap. So, for our purposes (which is soap making), all we need to worry about is whether we’re making a solid bar of soap or making liquid soap. But what’s the difference between the two? One other difference is that you tend to get more lather from the potassium hydroxide than the sodium hydroxide. Sodium Hydroxide (NaOH) is a royal pain in the butt to get it to dissolve in Methanol. I have read several different articles and a lot of them seem to mention that there is potassium in shaving soap because it helps give a better lather, but none of them seem to mention the softer soap. Although we use the terms lye and caustic soda interchangeably, they are slightly different from each other, because lye is a general term while caustic soda is a specific name. Main Difference – Potassium Hydroxide vs Sodium Hydroxide. Potassium Hydroxide (KOH) however, will begin dissolving almost on contact with methanol and dissolves extremely fast by comparison. In manufacturing soaps, both potassium hydroxide and sodium hydroxide are used in saponification, a process that converts fats into soap. Potassium hydroxide and sodium hydroxide are made with two different metals - sodium and potassium. As to why one makes a softer soap than the other, I can't tell you, but it might suffice to say that they are very different in many ways, for example the amount of KOH (potassium hydroxide) required to neutralize x grams of oil is different from the amount of NaOH (sodium hydroxide) Answer: No, I'm afraid they are not interchangeable. Potassium Hydroxide it used to make liquid soap and Sodium Hydroxide is used to make bar soap. Soaps are sodium or potassium salts of fatty acids, prepared in a chemical reaction called saponification. Sodium Hydroxide or Potassium Hydroxide for soapmaking. Potassium hydroxide and sodium hydroxide react with triglycerides in the same way by dissolving the triglycerides, which allows methanol to bond with fatty acids, the foundation of biodiesel … I want to make a shaving soap and do it all myself. Likewise, both compounds can be used to make biodiesel. The key difference between lye and caustic soda is that the term lye may refer to either sodium hydroxide or potassium hydroxide, whereas the term caustic soda refers only to sodium hydroxide.. Does it have more water in it, for example, to make it liquidy? It just LOVES to keep on hanging around…in solid form. It’s either sodium hydroxide or it’s potassium hydroxide. Sodium and potassium are highly reactive chemical elements that can be found in group 1 of the periodic table and are also known as alkali metals.They are s block elements because they have their valence electron in the outermost s orbital. by Anonymous Are sodium hydroxide and potassium hydroxide interchangeable in soap making?