Buchi B-585, Руководство по эксплуатации

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Glass Oven B-585
5.4.5 Working procedure for a simple distillation
The liquid to be distilled is placed in the vertical glass tube
with having only a single ground-glass joint using a pipette.
The glass tube can be filled up to the „max“ mark. The
desired number of glass balls are connected to each other
and secured against unwanted release with the clips. The
ball tube is connected to the vapour duct and pushed into
the oven. The aperture is closed and the electrical drive is
tur ned on. The oven temperature is increased until distilla tion
begins. This temperature can be anywhere between 10-40
°C above the sample's boiling point.
If you are distilling in a vacuum, then the ground-glass joints
must be lightly greased.
If the user is only interested in the distilled product and not in
the residue, the first ball that is sticking out of the oven can
be cooled. The platform with cooling dish which is mounted
on the device can be used to accomplish this. By connecting
the glass stopcock to a vacuum source, the boiling point of
thermolabile substances can be suitably reduced.
If the goal of the distillation is the distilled product and not
the residual product in the oven, then you should regulate
the vacuum and not operate under high vacuum conditions
In order to guarantee the longest possible lifespan of the
glass balls, the iris diapharm aperture should not be closed
so tightly that it makes contact with the glass ball or joints
when the rotation drive is turned on.
5.4.6 Working procedure for a rough separation
of a mixture with several components
Mixtures can be partially separated if the difference in the
boiling points between the individual components is fairly
large (> 20C°). All of the glass balls are placed in the oven
except for the glass ball farthest right. The temperature is
increased until distillation begins. The first fraction is caught
in the far right ball. If the vo lu me of the first fraction stops
increasing, then the distillation of the fraction with the lowest
boiling point is complete. The next ball is pulled out of the
oven and the temperature is
increased again.
When working with thermolabile substance, it is also recom-
mended that the boiling point is lowered by connecting to
a suitable vacuum source.
5.4.7 Aeration
After having finished vacuum distillation (position A), the de-
vice is turned off and the aeration cock is turned to position
B. You may now turn off the vacuum pump. By turning to
position C, the distil lation chamber is aerated either with the
air in the environment or, with the corresponding connection,
a safe, inert gas.
Fig. 20: Aeration stopcook
5 Operation