If you need a surfactant, the first things you should consider are:
• (glucose or sucrose + fatty acid) esters : non-ionic, biodegradable, edible
• (choline chloride + fatty acid) esters : cationic, biodegradable
• sodium alkyl sulfonates : anionic, hydrolysis resistant, biodegradable
Sugar esters are finally being used in some soaps. Good. One way to make them is with enzymatic transesterification of sugar and triglyceride.
With H2O2 + UV treatment for initial sterilization, adding a small amount of choline chloride ester of fatty acid could replace water chlorination!
Note that choline esters are more stable in acid than base. Try to keep the pH of water based compositions using them <6.
Alkyl sulfonates can be made from alkenes and sodium bisulfite with a free radical addition. Ethylene can be oligomerized to linear alpha-olefins, which are perhaps the most obvious choice, but you can also use something like ethyl oleate.
Why not other things?
sodium salts of fatty acids (aka standard bar soap)
• poorly soluble in "hard" water
• tends to form films on surfaces
alkyl sulfate esters
• sulfonates should be cheaper
• they're weak alkylating agents
fatty alcohol ethoxylates
• sulfonates and sugar esters should be cheaper
• considering that ethoxyacetic acid is bad for humans, some metabolites are probably bad
other cationic surfactants
• (choline chloride + fatty acid) esters should be cheaper than most of them
• most of them seem somewhat bad for humans
Fluorosurfactants are very bad. They are all environmental hazards, and I think they should be banned for everything except teflon production. (And I think teflon is overused; silicone is often better.) Stain/water repellants (eg Scotchguard) and firefighting foams have been notable sources. They're also used in ski wax. Yes, various toxic substances have been used for firefighting; carbon tetrachloride was once liked for fire suppression, and now there are fluorosurfactants.
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