[dodge305]

I am trying to find out how rapidly C2H4O4S (Ethylenesulfate) will absorb moisture from the atmosphere. Currently we do not have a climate controlled method of adding this chemical to our mixing vessel and it will have brief exposure to air.  The samples we mix in the glove box will be in a moisture free environment, but the larger mixing vessel will not and I need to know how quickly it will absorb moisture from the atmosphere and what kind of effect it may have on the quality of the chemical itself.  Everything I have been able to find to this point is very generic.

Thank You,

[Corribus]

It will depend on humidity level, obviously, and may not scale linearly. Do you have access to a thermogravimetric or sorption analyzer?

[dodge305]

Corribus, thank you for your reply, unfortunately we have neither.  For our normal production nothing is exposed to the atmosphere, but the installation of this new mixing vessel is not complete but we are being asked to produce a sample batch and this one additive will have to be added manually. It will be done in the plant and the humidity level here in the South ranges from 45% to 90% depending on the day.  I know the question is ambiguous at best, but we are trying to get an idea of how quickly the moisture will effect the ES and what it can do to the quality.

[Arkcon]

Briefly, no.  The rate of moisture absorption will depend on many things, in addition to the above, surface area exposed, air flow while mixing, and maybe other factors.  You will simply have to generate experimental data for your own system.  The effect moisture will have will likewise depend on your application.  You may have to let it all happen, and measure it after the fact, and determine what moisture level is unacceptable.  Or perhaps customers will have specs that they need.

[dodge305]

Thank you Arkcon. 

Rather than the rate, I can ask this.  Would ethylenesulfate be considered a deliquescent material or a hygroscopic material?