Parr Instrument Series 5500 - Manual (Page 11)

Compact Micro Reactors
w w w . p a r r i n s t . c o m 11
Do Not Overfill the Vessel
Always watch the pressure gage closely when admit-
ting gas so as not to exceed the maximum working
limit. Remember that any subsequent increase in tem-
perature will raise the pressure. Also, be sure that the
amount of liquid placed in the vessel is carefully con-
trolled. As a general rule, the liquid charge should not
exceed two-thirds of the capacity of the cylinder. Too
much liquid in the vessel can lead to development of
dangerous pressures if sufficient space is not provided
for expansion when the liquid is heated. This hazard
is explained in greater detail in a warning statement
included in the Instruction Manual No. 230M.
Releasing Pressure
Use the gas release valve to reduce the pressure in the
vessel if the reactor is accidentally overcharged when
filling. Use this valve also to release any excess pres-
sure during a run and to exhaust the vessel at the end
of a run. If the discharge gases are flammable or toxic,
discharge to an exhaust hood or to any other safe
release point.
Withdrawing Liquid Samples
Liquid samples may be withdrawn from the sampling
valve attached to the same adapter as the gas inlet
valve whenever the vessel is pressurized. Always
close the inlet valve before withdrawing a liquid sam-
ple and open the sampling valve cautiously because
liquid will be discharged with considerable force. Be
particularly careful if the temperature of the sample is
above its boiling point at atmospheric pressure. If so,
it will “flash” and be lost as soon as it is released from
the vessel. This problem can be avoided by connect-
ing an optional 4351 Sample Collection Vessel to the
sampling valve to collect the liquid into an appropriate
receiver. The addition of a small amount of gas can be
used to clear the dip tube between liquid samples so
that the next sample drawn through the tube will truly
be representative of the mixture.
Initial Operating Test
Read all operating instructions carefully so as to be
well acquainted with the correct procedures for han-
dling the vessel and for operating the controller and
other accessories. An initial operating test should be
made, with only water, to check the apparatus before
starting the first experimental runs. For this initial test,
fill the cylinder not more than half full of water and run
the temperature up to 150ºC while checking the appa-
ratus for leaks and observing the performance of the
reactor controller.
Accessories
Liners
Glass or PTFE liners can be furnished to fit most
Parr reactors. These liners slide into the cylinder.
Although they will not keep corrosive vapors from
reaching the surfaces of the cylinder and head, they
make it much easier to add and remove liquid reac-
tants, and they give some protection to the cylinder
when working with corrosive solutions. It must be
noted, however, that adding a PTFE liner will slow
the heat transfer rate into the vessel, and it may be
necessary to adjust the temperature control method
to prevent overheating.
Liner Part Numbers
Fits ID Cylinder
Size
Glass Liner PTFE Liner
1.3” 50 mL 1431HC 1431HCHA
1.3” 100 mL 1431HC2 1431HC2HA
Spare Parts Kit
Spare parts kits are available for these reactors. The
kits will provide a reserve supply of parts and tools
sufficient to handle most normal replacements and
emergency repairs during a year of heavy usage.
The kits contain small perishable items required for
continuous operation including gaskets, bushings,
rupture discs and seals. They can be ordered from
any Parr Dealer or direct from the Parr Instrument
Company. The order must specify the reactor size
and indicate type of rupture disc, stirrer drive and
whether it has a flat-gasket or O-ring closure. It is
most advantageous to provide the complete vessel
number from the head or cylinder.