Molasses Rust Removal

[Tony Wheeler]

Originally Posted by Bob Carriere

What is it in molasses that does the derusting...... the potassium content??? and if so would not a weak potassium acid bath be cheaper, faster, less sticky and stinky without being lethal to the environment?????

Apologies Bob, I've only just stumbled on your question. I've never given much thought to the molasses method but the active agents will be siderophores: "Siderophores (Greek: "iron carrier") are small, high-affinity iron chelating compounds secreted by microorganisms such as bacteria, fungi and grasses. Siderophores are amongst the strongest soluble Fe3+ binding agents known."

One candidate may be Enterobactin: "Enterobactin is a high affinity siderophore that acquires iron for microbial systems. It is primarily found in Gram-negative bacteria, such as Eschericia coli and Salmonella typhimurium."

E. coli may explain the stink you mention Bob. However it's really anybody's guess what you're growing in there. Molasses is rich in nutrients so you're basically creating a giant petri dish. It will be colonized by all manner of airborne microorganisms, particularly in Spring and the warmer months when they're most prevalent. Plus of course whatever animal droppings happen to get in.

On the question of alternatives the ideal compound would be EDTA. It's a widely used synthetic chelating agent which I know about only in theory, but which I'm quite certain would be far superior to molasses method. The only question would be cost and availability in bulk, as it appears to be produced exclusively in China with minimum order quote in metric tons! However my search for "industrial grade EDTA" returned lots of these which you may be able to source locally:

EDTA.jpg


Meanwhile I found some on ebay which looks ideal for trialling:

http://www.ebay.com.au/itm/EDTA-4Na-...UAAOSwZd1VW2YO