▎ 摘　　要

Anaerobic digestion (AD) is an efficient technology that can efficiently convert organic waste into biofuel, but excessive ammonia nitrogen concentration will lead to failure of AD. In this study, a metal-organic framework (MOF)-derived porous metal oxide/graphene nanocomposite (FeMn-MOF/G) was first applied in AD to inves-tigate the mitigation effect of ammonia nitrogen inhibition. Five total solids (TS) concentrations of 8 %, 10 %, 12 %, 15 % and 20 % were set up for AD experiment to investigate the effect of FeMn-MOF/G on AD. The results showed that the average ammonia nitrogen adsorption capacity of FeMn-MOF/G in AD with different TS con-centrations was 102.68 mg/g, and the ammonia nitrogen adsorption effect decreased with the increase of TS. When FeMn-MOF/G was added to AD, the ammonia nitrogen concentration of the experimental group could be reduced to 2,086.00 mg/L, and the VFAs concentration was reduced to 1,510.34 mg/L. The methane production in each experimental group increased significantly, and the experimental group MOF-8 obtained the highest cumulative methane production of 321.35 mL/gVS, indicating that FeMn-MOF/G effectively mitigated the ammonia nitrogen inhibition,which promoteed the successful operation of AD. We characterized the prepared FeMn-MOF/G. The results of the vibrating sample magnetometer show that FeMn-MOF/G has excellent super -paramagnetic properties. Magnetic recycling is a promising method for the recycling of FeMn-MOF/G materials, which provides a broad prospect for the application of FeMn-MOF/G in AD.