Degreasing with aqueous cleaners?

[Prometheus21]

Hi all,

I have just recently joined this website, and it's my first post. English is not my mother tongue, so please bear with me. I hope I post this in the right forum, as it relates to use of degreasing chemicals.

Question background:

My company (Based in Norway) designs, manufactures and supplies filling equipment used for filling cylinders with different compressed industrial gases, like oxygen. Due to this the company has since the early '70s been degreasing all parts using trichloroethylene. Up until 2011 we had governmental approval to do so, long after it was phased out in other parts of the world. After this we transitioned to using Ensolv, which have worked up until now. Ensolv, Prosolv and the like are in the process of getting phased out as well. The use of solvents are rapidly disappearing due to a number of legislative actions, at least in Europe. Some of our greatest customers have already banned the use of all solvents across the board.

Due to this we have transitioned yet again to using aqueous cleaners and ultrasonic cleaning in our production. We strive to uphold the guidelines given in the Praxair GS-38 (Class 2 (oxygen) cleaning) standard, as this (in our experience) is one of the strictest guidelines for oxygen cleaning.

In this standard there are mentioned some approved alkaline aqueous cleaners for oxygen cleaning; e.g. Blue Gold, Tramos & Beyond 2001&2005. (My apologies for brand-naming, I hope that is okay.) Some of our biggest customers have strict demands when it comes to upholding this standard, and will not approve the use of other aqueous cleaners.

My questions:
1. Do any of you guys have experience using any of the cleaners mentioned above? Care to share? To my knowledge Tramos is a European brand, whilst the others are from The United States.
2. Due to our own experience with some of the cleaners mentioned above we are now looking at Beyond 2001 from Today & Beyond industrial cleaners; the available documentation is old but looks promising. I do however wonder if any of you have experience with this vendor? Or can vouch for their legitimacy as their website and marketing seems...lacking to say the least.

Thank you for your time, and I apologize for the wall of text.

 

[georgeverghese]

I was operations engineer at an air separations plant in the early 80s', and we used perchloroethylene for degreasing the oxygen compressors too after maintenance. Gone out of fashion now.
Supercritical CO2 removes all sorts of organics, and Wiki says it is a substitute for chlorocarbon solvents in degreasing applications. No details provided. Minimum pressure for sCO2 is about 100bar.

 

[Prometheus21]

That's sounds cool! I remember seeing the 1,1,1-trichloroethane ("tri") in action for the first time back in the day; man that solvent worked wonders. Bus as you say with the perchloroethylene; its gone out of fashion.

We have been looking into using supercritical CO2 for degreasing, as well as a vapour vacuum degreaser using a modified alcohol as cleaning agent. Unfortunately they were deemed too expensive; and aqueous cleaners were forced through as the only valid option by the company administration. It's a shame really, since the overall long-term cost would be lower.

That being said; one of the downsides we discussed with using supercritical CO2 as a degreasing method was that inorganic or ionic contaminants are insoluble in supercritical fluids with low polarities; like CO2.