Graphene-oxide modified polyvinyl-alcohol as microbial carrier to improve high salt wastewater treatment

• New GO–PVA material achieves 1.43 times more halotolerant bacteria immobilization.
• The lamellar structure of GO–PVA material supports bacterial immobilization.
• Immobilized microbial community was identified by PLFAs analysis.
• 32% higher removal efficiency of high salinity wastewater by GO–PVA material.

This work discussed the preparation and characterization of graphene oxide (GO) modified polyvinyl alcohol (PVA) for bacteria immobilization to enhance the biodegrdation efficiency of saline organic wastewater. GO–PVA material has lamellar structure with higher surface area to support bacterial growth and high salinity tolerance. It significantly stimulated the bacterial population by 1.4 times from 2.07×103 CFU/mL to 5.04×103 CFU/mL, and the microbial structure was also improved for salinity tolerance. Acinetobacter, Pseudomonas and Thermophilic hydrogen bacilli were enriched inside GO–PVA materials for glucose biodegradation. Compared to the CODCr removal efficiency with only PVA as the carrier (52.8%), GO–PVA material had better degradation performance (62.8%). It is proved as a good candidate for bioaugmentation to improve biodegradation efficiency in hypersaline organic wastewater.