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Vacuum requirements

Vacuum requirements

Vacuum requirements

(OP)
Is there anywhere I can find information on vacuum pressure requirements for lowering a solvents boiling point?

I would appreciate any help.

RE: Vacuum requirements

In an old copy of "HANDBOOK OF CHEMISTRY AND PHYSICS", published by "THE CHEMICAL RUBBER PUBLISHING COMPANY", there is a table of Vapor Pressure for Organic Compounds(Pressures Less Than One Atmosphere).  The table gives the temperatures at which the vapor pressure of the compound equals 1, 10, 40, 100, 400 and 760 mm Hg.  There appears to be in excess of 1,000 compounds listed.

This handbook should be in any science library.

Hope it helps.

RE: Vacuum requirements

A solvent boils when its vapour pressure (pvap) equals the pressure of the system (P).

pvap = P

pvap is a property of a solvent whose value increases with increasing temperature.

The relationship between pvap and t can either be found as a series of discrete values, as the previous correspondent popints out. An alternative source is the Antoine equation which describes the relationship thus:

loge(pvap) = A  +B/(C+ t)

where A,B,C are constants for a particular solvent.

RE: Vacuum requirements

You could try to investigate the feasibility of steam (or other inert) stripping which would be boiling by reducing the partial (effective) pressure available.

RE: Vacuum requirements

(OP)
Thanks trihydrate, Leclerc, and 25362, the help is much appreciated.

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