Bio-electro-Fenton　(BEF)　technology,　a　sustainable　and　energy-efficient　advanced　oxidation　process　(AOP),　has　been　developed　for　the　treatment　of　refractory　organic　wastewater.　This　study　introduces　a　novel　20　L　scale-up　BEF　reactor　utilizing　multiple　MoS2/carbon　nano-tube　(MoS2/CNTs)　coated　carbon/Polytetrafluoroethylene　(C/PTFE)　gas　diffusion　electrodes　(GDE)　as　cathodes　for　the　efficient　treatment　of　phenolic　wastewater.　MoS2,　acting　as　a　co-catalyst,　significantly　enhanced　phenol　removal　by　improving　Fe2+　recovery.　The　maximum　removal　rates　of　phenol　and　total　organic　carbon　(TOC)　reached　94　%　and　87　%,　respectively.　Computational　fluid　dynamics　(CFD)　simulations　of　velocity,　fluid　trace,　and　concentration　distribution　of　H2O2,　O2,　and　phenol　demonstrated　excellent　mass　transfer　and　diffusion　performance　of　the　scaled-up　BEF　reactor.　These　findings　suggest　that　the　scale-up　BEF　system　with　multiple　electrodes　is　a　promising　technology　for　the　degradation　of　phenol　and　may　also　be　an　attractive　strategy　for　the　treatment　of　refractory　organic　wastewater.　©　2024　Elsevier　B.V.