Catalytically Active Boron Nitride in Acetylene Hydrochlorination

This study presents the discovery that porous boron nitride (p-BN) is active in acetylene hydrochlorination, although boron nitride (BN) is generally considered chemically inert. An acetylene conversion of 99% is achieved with a vinyl chloride selectivity over 99% at 280 °C at a gas hourly space velocity (GHSV) of 1.32 mL min–1 g–1. By contrast, the commercially available crystallized hexagonal BN (h-BN) exhibits no catalytic activity. Furthermore, this p-BN is rather durable as demonstrated by a 1000 h lifetime test. Catalytic tests, spectroscopic characterization, and theoretical calculations indicate that the activity likely originates from the defects and edge sites. Particularly, the armchair edges of BN can polarize and activate acetylene, which then reacts with gaseous HCl giving vinyl chloride as the product.