Technoeconomic Evaluation of the Industrial Implementation of Catalytic Direct Nonoxidative Methane Coupling.

This paper presents a process design for catalytic nonoxidative natural gas conversion to olefins and aromatics, highlighting the opportunities and challenges concerning industrial implementation. The optimal reactor conditions are 5 bar and 1000 °C. Heat exchange over the reactor is challenging due to the high temperature and low gas pressure. Recovery of ethylene is economically unattractive due to the low ethylene concentration in the product stream, leading to a methane-to-aromatics process, recycling ethylene. Benzene is the most valuable product at an efficiency of 0.31 kg benzene /kg methane with hydrogen as a major valuable byproduct. Naphthalene, with a low value, is unfortunately the dominant product, at 0.52 kg naphthalene /kg methane . It is suggested to hydrocrack the naphthalene to more valuable BTX products in an additional downstream process. The process is calculated to result in a 107 $ profit per ton CH 4 .