ChemoSabe (Hive Addict)
05-12-04 01:00
No 506616
      Tetra vs. Tri     

Anyone know if there's a difference in the effectiveness of tetrachlorethylene as compared to trichlorethylene?

Both are sold, marketed and used as de-greasifying cleaners but are they similar enough to be used interchangably?

I would assume that the chemical difference would bee that tetra's molecule's got 4 atoms of chlorine as opposed to tri's 3.

Is this a wrong assumption?

The Shiite has hit the fan
 
 
 
 
    wareami
(Hive Addict)
05-12-04 05:39
No 506639
      Not far off base...     

Chemo: First a correction....followed by Ibee's experience...followed by technical data in comparison

Trichloroethylene more commonly known asTCE by industry or 1,1-2-trichloroethylene

Tetrachloroethylene more commonly known as PERC by industry or Perchloroethylene

Ibee first put the Trichloro through similar testing as Tetrachloro after the tetra was found to be a suitable extraction agent in battling gaaks.
The results of that testing concluded that the Trichloro was not as effective at removing polymers as Tetra.
This testing wasn't as all conclusive as it might appear because it hasn't been tryed in testing any of the newer gaaks...just up to and including dry-matrix formulations.
Some tests were performed using a 50%/50% mix of tetra/tri on the orangeI gaak species and failed to produce desirable results so the project was shelved as a failure.

With todays gaaks, partly because of the numerous variety, it's important to look for solvents that are selective in removing gaaks either in groups or one at a time.
Once this is accomplished in finding compatible solvents, it then becomes necessary to know which order of introduction into the extraction is most effective.
One solvent, or process even, can fuse gaak to the goodz making removal damn near impossible. Yes Ibee has created such conditions in the past.

Ibee would recommend that any bees interested in trying this in extraction, first try it on a small lot an determine it's effectiveness at removing or isolating newer gaaks.
It may prove to be helpful, at some stage.
But don't be too surprised if it fails miserably as it did at one time for Ibee.


Now for some brief data comparison:
Trichloroethylene (TCE)
CAS Registry Number: 79-01-6

(trichloroethylene; 1,1-2-trichloroethylene, 1,1-dichloro-2-chloroethylene, acetylene trichloride, andethylene trichloride)
HIGHLIGHTS: Trichloroethylene is a colorless liquid which is used as a solvent for cleaning metal parts. Drinking or breathing high levels of trichloroethylene may cause nervous system effects, liver and lung damage, abnormal heartbeat, coma, and possibly death. Trichloroethylene has been found in at least 852 of the 1,430 National Priorities List sites identified by the Environmental Protection Agency (EPA).
What is trichloroethylene?
Trichloroethylene (TCE) is a nonflammable, colorless liquid with a somewhat sweet odor and a sweet, burning taste. It is used mainly as a solvent to remove grease from metal parts, but it is also an ingredient in adhesives, paint removers, typewriter correction fluids, and spot removers.

Trichloroethylene is not thought to occur naturally in the environment. However, it has been found in underground water sources and many surface waters as a result of the manufacture, use, and disposal of the chemical.

Tetrachloroethylene (PERC)
CAS Registry Number: 127-18-4

(perchloroethylene, ethylene tetrachloride, 1,1,2,2-tetrachloroethylene)
HIGHLIGHTS: Tetrachloroethylene is a manufactured chemical used for dry cleaning and metal degreasing. Exposure to very high concentrations of tetrachloroethylene can cause dizziness, headaches, sleepiness, confusion, nausea, difficulty in speaking and walking, unconsciousness, and death. Tetrachloroethylene has been found in at least 771 of the 1,430 National Priorities List sites identified by the Environmental Protection Agency (EPA).

What is tetrachloroethylene?
Tetrachloroethylene is a manufactured chemical that is widely used for dry cleaning of fabrics and for metal-degreasing. It is also used to make other chemicals and is used in some consumer products.

Other names for tetrachloroethylene include perchloroethylene, PCE, and tetrachloroethene. It is a nonflammable liquid at room temperature. It evaporates easily into the air and has a sharp, sweet odor. Most people can smell tetrachloroethylene when it is present in the air at a level of 1 part tetrachloroethylene per million parts of air (1 ppm) or more, although some can smell it at even lower levels.

a little less conversation, a little more reaction