The objective is to determine the rate and mechanism of (1) sulfur poisoning and (2) of regeneration of metal catalysts used in synthesis gas conversion to hydrocarbon products. Auger electron spectroscopy (AES) is used for surface analysis, and in-situ reaction studies of deactivation and regeneration are combined with microreactor studies to quantify sulfur poisoning. An all-glass internal recirculation microreactor has been designed, fabricated, debugged and integrated into a metal-free feed gas and G. C. analysis system for kinetic studies of sulfur deactivation in CO hydrogenation. An UHV antechamber has been designed, built and connected with the Auger electron spectrometer to allow sample treatment at high temperature and pressure with subsequent AES analysis without atmospheric contamination. A gas-dosing, molecular-leak system has been installed on the AES vacuum chamber to allow in-situ sample treatment to bridge the high-pressure low-pressure gap. A mass spectrometer has been added to the system, and a computer is being interfaced with the spectrometer for improved data treatment and analysis at nano-ampere beam currents. The procedures for film preparation and cleaning have been developed; films are being used in all parts of the work.