High Pressure Laboratory

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Small Rocker Operation

Prepare the Solution and Glass Liner

  1. Obtain the liner from the labeled drawer in the HPL. The liner can be checked out in advance. Be sure it is the correct size for the volume desired and for the bomb to be used.
  2. Transfer the desired reactants into the liner being careful not to exceed the maximum volume specified.

Prepare the Pressure Vessel.

  1. Ensure that the vessel is empty. Use caution in case liquid is found in the bottom.
  2. Ensure the spring is inside the bomb.
  3. Lower the glass liner into the pressure vessel.
    1. Note ‘UP’ stamped on the outside of the pressure vessel
    2. Place the liner so that the hole in the side is facing the same direction as the ‘UP’ stamped on the vessel. This will minimize leakage from the liner.
  4. Place the head on top of the base and screw the closure head into place. Hand tighten only.

Load the prepared pressure vessel into the rocker.

  1. Insert the pressure vessel into the rocker with the stamped ‘UP’ facing up, making sure that it locks in place.
  2. Connect the U-shaped connection tube to the pressure vessel head. Note: If adjusting of the upstream connector is required, counter torque must be applied when tightening and loosening.

Purge/Pressurize the System

  1. Shut the cell door.
  2. Note that pressurizing and venting should be done slowly (~20 psi/sec) to minimize frothing and the subsequent loss of reactants.
  3. Purge the system three times with nitrogen to evacuate the air, helping to reduce the risk of explosion. Monitor the system pressure to ensure acceptable pressure stability.
  4. Purge the system three times with hydrogen (or your desired gas).
  5. Pressurize the system to the desired starting pressure.
  6. Close the gas cylinders, back off the regulators, isolate the supply header, and vent the regulator load side using the ball valve above the regulators.
  7. For maximum pressure integrity, shut the Small Rocker Isolation Valve.

Program the Experiment Run

Program your desired temperature. Refer to page 13 for specific instructions. Start the rocker, if desired.

Monitor the Experiment

NOTE: It is recommended that you monitor the system periodically until you are comfortable that the pressure is holding and that the temperature is correctly following its programmed profile. Since P1/P2 ≈ T1/T2, pressure will increase with temperature.

Vent/Purge System

  1. After the experiment is finished, slowly vent off the hydrogen (or other gas used).
  2. Purge the system three times with nitrogen to expel the excess hydrogen.


  1. Disassemble the apparatus in the opposite order that you assembled it.
  2. Be sure to clean up and put everything back in its proper place. If any of your solution spilled inside the pressure vessel, be sure to dispose of it properly and clean and dry the vessel with air.

University of Illinois at Urbana-Champaign
High Pressure Laboratory
School of Chemical Sciences
Roger Adams Lab Penthouse
600 S. Mathews Avenue
Urbana, IL  61801
Dr. William A. Boulanger
Faculty Advisor
wboulang [at] illinois [dot] edu
217-621-4023 (cell)
scs-webmaster [at] illinois [dot] edu