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The utilization of Anaerobic Digestion (AD) technology for biogas and energy generation is often hindered by high concentration of sulfur-containing compounds in wastewater and consequential hydrogen sulfide (H 2 S) in biogas. In this work, we demonstrated a process, where independent mechanisms of anaerobic microorganisms and an inorganic reactive adsorbent (zinc oxide nanowires) worked synergistically to remove soluble sulfide (HS − ) and prevent H 2 S formation during AD. Using a model aqueous sodium sulfide (Na 2 S) system, the nanowires (dosage 1 g/L) effectively removed sulfides from the Na 2 S solution to a maximum of 625 mg S 2− /L per gram of ZnO. During 24 h and 3-day long (involving three consecutive sulfate feeding cycles) AD studies using anaerobic microbial medium (2 g/L SO 4 2− and 1 g/L ZnO), no decrease in methanogenic activity and biogas production were observed using the ZnO nanowires, indicating that the nanowires can reduce the sulfide toxicity during AD. The post-process analysis of the recovered nanomaterial using energy-dispersive X-ray spectroscopy and X-ray diffraction showed the presence of sulfur and zinc sulfide (ZnS), respectively, validating HS − removal by the nanowires. This process intensification approach of combining AD and H 2 S removal into a single process step will help extend AD technology to high sulfate containing wastewaters. [ABSTRACT FROM AUTHOR]