Reactive Adsorption of Arsine on Sulfur –containing Carbons: Role of Surface Chemistry in the Oxidation Process at Ambient Conditions

Introduction Arsine is widely involved in the field of semiconductor synthesis as a doping material [1]. Because of its high toxicity, any excess of this gas in the preparation process should be removed. Moreover, arsine appears as a trace contaminant of the syngas used in methanol synthesis and its presence is associated with catalyst poisoning [2]. Considering these two aspects, efficient technologies to separate arsine from air or syngas are needed. Toward this purpose, several adsorbents such as alumina and activated carbon have been tested [3, 4]. Whereas some studies report the use of virgin adsorbents, the modification of these materials with metal oxides, such as copper oxide, is also presented as a promising method to remove arsine [3, 4]. The active sites for arsine binding are provided by both the oxide and the carbon support [4]. It was shown that water can bind to these active sites faster than arsine and thus decreases the removal efficiency [5]. Nevertheless, the nature and role of these active centers were not explored. The objective of this study is to investigate the role of oxygen and sulfur-containing groups on the surface of microporous carbon in the removal of arsine.