ION-IMPLANTATION OF RANEY COPPER-CATALYSTS

Raney copper catalysts promoted with zinc are known to catalyse both m ethanol synthesis and the water-gas shift reaction. In this work, samp les were implanted with Zn+ ions using a specially designed free-powde r target holder, and then tested for water-gas shift activity in a che mical microreactor. Beneficial effects in the form of longer sustained activity at higher conversion were observed, extending over several h undred hours, especially for the higher zinc doses. Similar results we re obtained with a chromium implant. Control implants with inert gas i ons produced no beneficial effects. This study represents the first ex ample of the use of ion implanted promoters in catalysis, on a bench t op reactor scale.