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[Laminar]

I want to ask, how to define OLEUM (say 20%) in HYSYS and which property prediction pakage(s) should be used?

[Technical Bard]

I want to ask, how to define OLEUM (say 20%) in HYSYS and which property prediction pakage(s) should be used?

While possible, sulfuric acid and oleum is highly non-ideal. I have done this with the Aspen ELECNRTL model (with adjustments to match published data), but the real problem is that sulfuric acid is an odd substance. It is highly hygroscopic - it will absorb water out of the air. Dilute sulfuric acid is 100% dissociated and highly corrosive. Above 93wt%, there is insufficient water to allow for dissociation and the acid becomes less corrosive (to many materials).


Sulfuric acid also exerts very little vapour pressure at high concentrations (below 100% purity), but suddenly does exert a vapour pressure when it goes past 100% purity - this is oleum (basically SO3 dissolved in H2SO4). The SO3 exerts a vapour pressure (see http://pubs.rsc.org/...tf/tf9403500345).