Laser cleanup of H2S from synthesis gas

Hydrogen sulfide at the 10 ppm level has been selectively stripped from a CO + H2synthesis gas by photolysis with an ArF laser. The sulfur in the atomic or radical form is irreversibly removed by a metal surface. Spectroscopic and quantum yield data are presented. An H2S spectroscopic selectivity less than 10⁷was measured in the 210-220 nm range, a wavelength range compatible with Raman-shifted ArF or KrF lasers. The laser purification method described here is a potential approach to achieve sulfur impurity levels greater than 0.1 ppm. This method is of potential industrial significance for extending the lifetime of syngas metal catalysts.