High Pressure, High Temperature Infrared-Ultraviolet-Visible Spectrophotometer Cell for <i>in situ</i> Catalyst Studies

Abstract

An ir and uv-visible spectrophotometer cell for recording the spectra of solutions at elevated temperatures and pressures has been designed and fabricated. The cell is used for characterization of reactive catalyst species and reaction intermediates which exist only at conditions above ambient. The temperature and pressure maxima are limited by the window material which, in turn, is determined by the spectral range to be examined. Large windows, variable path length, and relatively compact design permit the use of the cell interchangeably among a variety of commerically available ir and uv-visible spectrophotometers without the need for special instrument modifications. The cell with CaF2 windows has been applied to studies of catalyst solutions at reaction conditions up to 100 atm at 200° C without any suggestion of window or cell failure. The design and construction of the cell are reported.