Progress and prospects in catalytic ethane aromatization

The direct transformation of ethane, the second largest component of natural gas, to higher-valued petrochemical feedstocks has been investigated for nearly 50 years, yet the recent shale gas revolution has caused it to become increasingly lucrative. While steam cracking has been central in direct ethane conversion, catalytically-driven processes appear to have considerable potential for application to the large-scale production of unsaturated hydrocarbons, such as ethylene and aromatics, from ethane. The present paper aims to address state-of-the-art knowledge of the relevant catalyst formulations and their performances in the direct conversion of ethane into aromatics hydrocarbons, mainly benzene, toluene, and xylene. This entails a comprehensive exploration of early patents from the industrial players as well as scientific papers in this field, focusing on how zeolite acidity and metal function affect catalytic activity, selectivity and stability. The review is concluded with a general perspective on directly-catalyzed ethane conversion.