Posted: Sat Dec 16, 2006 12:35 am
YAY!!! Finally something that I can actually give input to and sound somewhat intellegent!!! (I was a chem major in college...)
Lye is indeed Sodium Hydroxide (NaOH) and is EXTREMELY basic. You guys are correct that it is the polar opposite of Acid. It is very very good and breaking down proteins in nature (read...breaking down your body) so make sure that you treat it with respect. It would work well in the tank in place of TSP and it shouldn't react to the steel TOO MUCH if used in an EXTREMELY LOW CONCENTRATION. The added bonus is that you could use far FAR less of this product to get your tank running than you would use washing soda. The problem is this...lye will cause flash rust in a heartbeat once you take the part out of the tank. It is similar in nature to Washing Soda or baking soda in that these three products are all bases. To dispose of the liquid with minimal side effect, one could add hydrochloric acid (very slowly and over a longer time) at an equal weight to the original addition of lye when the tank was set up, and all you would have would be water and SALT...and A TON OF HEAT!!!! If you added the hydrochloric acid slowly enough, then the reaction would not be too violent.
TSP is also basic in solution, but mildly so. It is used frequently in the food industry and in the chemical industry to help RESIST changes in pH (measure of acidity) of a product when an acid is added. Because it is only very mildly basic, it does not STRONGLY promote flash rust in parts that go through the electrolysis tank.
The reason TSP works is that it readily ionizes in solution to its positive part (Na+) and negative (PO4-) parts. This allows the neutral water to now become a conductor from between the two poles if your tank (the positive and negative lead). Lye also breaks down to its components in solution (Na+) and (-OH) but the (-OH) is VERY STRONGLY charged to the negative side of the coin. In the food industry (specifically the Dairy industry) NaOH (commonly called "Caustic" by those in the business) is used to "scrub out" the stainless steel lines in a pasteurizing system when a bunch of the proteins and sugars have gotten "baked on" the lines of the plant. Over time, this product can and will etch the stainless steel.
Now, I can speculate a little bit. When they say "phosphorus free" in the TSP, I think that they are referring to "free phosphorus" in the product. Phosphorus is extremely poisonous, and that is the reason for the legislation, in my opinion. Cecil, I think that the reason you did not have luck with the concentrated TSP (Phosphorus free) is that when you diluted it in your tank, it might have gotten "over diluted" by adding water. I have not seen the product on the shelf at the Big Orange Store, but I'll bet that it is probably no more than a 30 - 60% solution...there has to be a point where the solution is "saturated" and cannot carry any more of the TSP salt in it. Does the bottle say how much it is concentrated?
Sorry for the long post, but I don't think that the phosphorus free TSP is the cause of the tank not working, but the concentration (or lack of concentration) in the tank would be the problem... Here is an experiment...get a bottle of the concentrate, cut off the top of the bottle and make a "mini tank" for a small part. Don't dilute the TSP at all, but just hook it up the way it is...I'll bet you get bubbling and WORKING electrolysis.
Has anyone tried plain old table salt as a catalyst in an electrolysis tank? It breaks down to (Na+) and (-Cl) and is fairly neutral...of course, salt causes cars to rust when exposed to this on the road, but would it be worse than Washing Soda for flash rust? Basically, any "salt" will break into its positive and negative components in solution with water, and these ions will conduct electricity.
OK... I'll shut up now!!!
Mike in La Crosse, WI
Lye is indeed Sodium Hydroxide (NaOH) and is EXTREMELY basic. You guys are correct that it is the polar opposite of Acid. It is very very good and breaking down proteins in nature (read...breaking down your body) so make sure that you treat it with respect. It would work well in the tank in place of TSP and it shouldn't react to the steel TOO MUCH if used in an EXTREMELY LOW CONCENTRATION. The added bonus is that you could use far FAR less of this product to get your tank running than you would use washing soda. The problem is this...lye will cause flash rust in a heartbeat once you take the part out of the tank. It is similar in nature to Washing Soda or baking soda in that these three products are all bases. To dispose of the liquid with minimal side effect, one could add hydrochloric acid (very slowly and over a longer time) at an equal weight to the original addition of lye when the tank was set up, and all you would have would be water and SALT...and A TON OF HEAT!!!! If you added the hydrochloric acid slowly enough, then the reaction would not be too violent.
TSP is also basic in solution, but mildly so. It is used frequently in the food industry and in the chemical industry to help RESIST changes in pH (measure of acidity) of a product when an acid is added. Because it is only very mildly basic, it does not STRONGLY promote flash rust in parts that go through the electrolysis tank.
The reason TSP works is that it readily ionizes in solution to its positive part (Na+) and negative (PO4-) parts. This allows the neutral water to now become a conductor from between the two poles if your tank (the positive and negative lead). Lye also breaks down to its components in solution (Na+) and (-OH) but the (-OH) is VERY STRONGLY charged to the negative side of the coin. In the food industry (specifically the Dairy industry) NaOH (commonly called "Caustic" by those in the business) is used to "scrub out" the stainless steel lines in a pasteurizing system when a bunch of the proteins and sugars have gotten "baked on" the lines of the plant. Over time, this product can and will etch the stainless steel.
Now, I can speculate a little bit. When they say "phosphorus free" in the TSP, I think that they are referring to "free phosphorus" in the product. Phosphorus is extremely poisonous, and that is the reason for the legislation, in my opinion. Cecil, I think that the reason you did not have luck with the concentrated TSP (Phosphorus free) is that when you diluted it in your tank, it might have gotten "over diluted" by adding water. I have not seen the product on the shelf at the Big Orange Store, but I'll bet that it is probably no more than a 30 - 60% solution...there has to be a point where the solution is "saturated" and cannot carry any more of the TSP salt in it. Does the bottle say how much it is concentrated?
Sorry for the long post, but I don't think that the phosphorus free TSP is the cause of the tank not working, but the concentration (or lack of concentration) in the tank would be the problem... Here is an experiment...get a bottle of the concentrate, cut off the top of the bottle and make a "mini tank" for a small part. Don't dilute the TSP at all, but just hook it up the way it is...I'll bet you get bubbling and WORKING electrolysis.
Has anyone tried plain old table salt as a catalyst in an electrolysis tank? It breaks down to (Na+) and (-Cl) and is fairly neutral...of course, salt causes cars to rust when exposed to this on the road, but would it be worse than Washing Soda for flash rust? Basically, any "salt" will break into its positive and negative components in solution with water, and these ions will conduct electricity.
OK... I'll shut up now!!!
Mike in La Crosse, WI