Type-II MHC Pressure Vessels

Constructed with the financial support of SNSF, Société Académique de Genève, Fondation Ernst et Lucie Schmidheiny, Fondation Ernest Boninchi and the University of Geneva.

These pressure vessels are equipped with a custom-developed semi-permeable hydrogen membrane (Shaw membrane). They have a water-cooled cold seal on both ends, the Shaw membrane is introduced from one end, whereas the high-pressure argon connection is on the other end. The vessel is placed in split furnaces and the furnace-vessel assembly can be rotated all together to facilitate rapid quenching or heating, and the in situ fracturing of quartz.

Photograph and schematic drawing of the Type-II MHC pressure vessel assembly

Performance Highlights:

  • Achievable pressure and temperature up to 200 MPa and 1100 oC, argon pressure medium
  • Rapid quench and instant heating capability by dropping the capsule between the hot-zone and water-cooled ends
  • Pressure monitoring by digital pressure transducers, the calibration of which is regularly checked against an analogue Heise gauge on the main line
  • 5 cm long hot zone with temperature uniformity better than 15 oC measured 1000 oC nominal temperature (inside the vessel under argon pressure with water cooling on, 5 degrees tilted position)
  • Redox control via semi-permeable hydrogen membrane
  • Attainable fO2 in water-saturated phase assemblages between FMQ-0.5 to FMQ+5, fO2 accuracy better than 0.3 log units, precision better than 0.1 log units.
  • Robust, pressure leak-free design
  • Heavy-duty transparent polycarbonate safety shielding