TY - JOUR
T1 - Methane conversion to aromatics via chemical synergy with OCM
T2 - Effect of periodic operation, temperature profile, and catalyst loading
AU - Haki, Maria
AU - Linke, Patrick
AU - Costa, Izabel Medeiros
AU - Al-Rawashdeh, Ma'moun
N1 - Publisher Copyright:
© 2025 The Authors
PY - 2025/2/22
Y1 - 2025/2/22
N2 - The transition from indirect to direct methane conversion marks a significant advancement in chemical processing. One promising direct reaction is methane dehydroaromatization, which converts methane to aromatics in a single step with zero CO2 emissions. However, the commercialization of MDA faces major challenges including thermodynamic limitations, rapid catalyst deactivation, and high temperature requirements. Integrating MDA with another reaction offers a potential solution to these challenges combined. This work explores the potential opportunities and limitations for chemical synergy when coupling the oxidative coupling of methane (OCM) to MDA through mass integration. Experimental studies were conducted by passing the oxidative coupling of methane (OCM) reactor effluent to a downstream MDA reactor. Periodic feeding of OCM to the MDA catalyst showed limited improvement, indicating that OCM composition alone does not maintain stable MDA performance. Varying the temperature over time in MDA reactor demonstrated that C2 coming from OCM contribute to aromatic production even at low temperatures (450 °C). However, at such temperature, the conversion of CO2 to CO and CH4 to aromatics does not occur, highlighting the need for high operating temperatures in the OCM-MDA coupling process. The coupling of OCM and MDA was tested with different MDA space velocities as 3750, 1875, and 1250 mL/g/h, corresponding to 0.2 g, 0.4 g and 0.6 g catalyst loading, respectively. The case of 1250 mL/g/h maintained a stable 14 % conversion and 2.5 % yield of benzene over 10 h, converting all CO2 to CO. Characterization using TGA, Raman spectroscopy, and XPS on spent catalysts indicated limited carbon removal by OCM effluent, and confirmed that CO2 is causing the oxidation of Mo2C to MoOx. A reaction scheme for the OCM-MDA coupling using Mo/ZSM-5 is proposed to guide future exploration of this promising two-step process.
AB - The transition from indirect to direct methane conversion marks a significant advancement in chemical processing. One promising direct reaction is methane dehydroaromatization, which converts methane to aromatics in a single step with zero CO2 emissions. However, the commercialization of MDA faces major challenges including thermodynamic limitations, rapid catalyst deactivation, and high temperature requirements. Integrating MDA with another reaction offers a potential solution to these challenges combined. This work explores the potential opportunities and limitations for chemical synergy when coupling the oxidative coupling of methane (OCM) to MDA through mass integration. Experimental studies were conducted by passing the oxidative coupling of methane (OCM) reactor effluent to a downstream MDA reactor. Periodic feeding of OCM to the MDA catalyst showed limited improvement, indicating that OCM composition alone does not maintain stable MDA performance. Varying the temperature over time in MDA reactor demonstrated that C2 coming from OCM contribute to aromatic production even at low temperatures (450 °C). However, at such temperature, the conversion of CO2 to CO and CH4 to aromatics does not occur, highlighting the need for high operating temperatures in the OCM-MDA coupling process. The coupling of OCM and MDA was tested with different MDA space velocities as 3750, 1875, and 1250 mL/g/h, corresponding to 0.2 g, 0.4 g and 0.6 g catalyst loading, respectively. The case of 1250 mL/g/h maintained a stable 14 % conversion and 2.5 % yield of benzene over 10 h, converting all CO2 to CO. Characterization using TGA, Raman spectroscopy, and XPS on spent catalysts indicated limited carbon removal by OCM effluent, and confirmed that CO2 is causing the oxidation of Mo2C to MoOx. A reaction scheme for the OCM-MDA coupling using Mo/ZSM-5 is proposed to guide future exploration of this promising two-step process.
KW - Chemical and thermal synergies
KW - Methane dehydroaromatization
KW - Oxidative coupling of methane
KW - Process development
KW - Reaction coupling
UR - https://www.scopus.com/pages/publications/85218277805
U2 - 10.1016/j.fuproc.2025.108189
DO - 10.1016/j.fuproc.2025.108189
M3 - Article
AN - SCOPUS:85218277805
SN - 0378-3820
VL - 270
JO - Fuel Processing Technology
JF - Fuel Processing Technology
M1 - 108189
ER -