Operating Objectives
The Lab-3
is designed to distill thermally sensitive organic and silicone
compounds in the molecular weight range of 150+ AMU at vacuums
from 1 to 700 X 10-3 Torr. Some examples of distillation
from the Lab-3 include Fatty
acid amides, Dimer acids, Epoxy resins, Drying oils, Monesters,
Di-octyl phthalate, and Vitamin A Tocopherols (Vitamin E).
Material
Handling
The Lab-3
high vacuum still is designed as a batch / continuous distillation
unit. Figure to left illustrates the flow of the process material
through the still. Green designates Feed material, Blue Residue
and Yellow distillate.
The material flows by gravity from the Degasser reservoir: where
the material is also degassed by removing small amounts of low
boiling materials and trapped gases to enable more efficient
vacuum distillation at the next stage.
The
material then flows via the rotor feed valve (17) on to the
center of the heated, spinning rotor (5) in the high vacuum
distillation chamber. On the rotor, the material spreads out
into a thin film (0.05 mm thick).
As the material spreads across the rotor, a certain portion
(the distillate) evaporates. The fraction which distills is
selected by the operator. Once set, this remains constant until
the run is completed or until new conditions are selected.
The distillate vapor condenses on the condenser in the vacuum
chamber and is pumped from the system via the distillate collect
valve (15) into the distillate collector (14).
The portion which does not distill (the residue) moves off the
edge of the rotor to be trapped by the gutter and is pumped
from the still via the residue collect valve (16) into the residue
collector (13). The residue may be recycled by opening the recycle
valve (18).
Depending upon the feedstock material or process requirements,
either the distillate or the residue may be your final product.
In many cases both may be of value.
Vacuum System
The Lab-3
is designed to distill materials in the pressure range from
1 to 700 X 10-3 Torr.
The lower
the distillation pressure, the lower the heat required to
effect distillation, the lower the chance of destroying the
product and the lower the energy costs of the purification
process.
The Lab-3 includes a complete, fully valved vacuum system (See
Figure 1 Purple lines). This fully valved system allows the
operator to isolate certain parts of the system while making
desired adjustments, thus eliminating the need to completely
shut the system down.
All
manifolds are stainless steel with standard vacuum fittings
for easy disassembly/assembly for cleaning.
The mechanical pump is a direct drive rotary vane vacuum pump.
It is used as a forepump for the diffusion pump, and to rough
pump the degasser, the distillation, the distillate and the
residue chambers.
The High Vacuum pump is a rugged 2" diffusion pump enabling
the distillation chamber to operate under high vacuum.
An
automatic temperature controller monitors the output water temperature
of the diffusion pump and meters the flow of cooling water for
maximum pump efficiency and minimal amount of water usage.
The trap valve removes easily condensable-vapors, or low boiling
volatiles so as not to contaminate the oils in the mechanical
and diffusion pumps and to prevent oil in those pumps from back
streaming into the chamber.
Control Center
The
Lab-3 control center contains all of the controls and readouts
required for operation:
Vacuum Readout: There is a two (2) - station pressure
monitoring section with leak detect mode. This enables the operator
to get accurate pressure measurements in the distillation chamber
and on the foreline. Plus leak detect function simplifies system
check out after reassemby.
Temperature Readout: There is an SCR temperature controller
which enables the operator to set and control the temperature
of the rotor.
The
thermocouple is located inside the rotor for true film temperature
measurement.
The control center also provides a variable power switch for
the addition of heat tapes if desired.
Complete Lab-3 System Standard
Bench Model
Part
Number: 285352
Still Assembly: Includes degassing feed chamber, 3" diameter
heated rotor, water-cooled condensing surface, feed valve, distillate
/ residue valves, and distillate / residue collecting vessels.
The residue collecting vessel is equipped with a recycle line
returning to the degassing chamber for multiple pass operation.
The still components are mounted on a stand and are easily accessible
for cleaning and maintenance. Wetted components are stainless
steel, viton seals and a minimum of glassware.
Pumping System: Includes 2" diffusion high vacuum pump,
mechanical pump, vacuum cold trap, vacuum manifold with valves,
and water manifold with valves. It is mounted in a cabinet which
connects to the Still Assembly via flexible hoses.
Control Center: Includes thermistor vacuum gauge, digital
temperature controller, individual switches for rotation, heater
mechanical and diffusion pump, and a variably switched power
outlet for the addition of heat tapes.
|
PERFORMANCE
SPECIFICATIONS |
Throughout
Capacity |
0 - 2 lbs/hr
(.9
kg/hr) |
Design |
Batch/Continuous |
Space and Utility Requirements
Myers
Vacuum
