Recycling strategies of spent V2O5-WO3/TiO2 catalyst: A review

•Spent V2O5-WO3/TiO2 catalyst cause environmental and potential safety problems due to its hazardous substance.•Recycling of the spent V2O5-WO3/TiO2 catalyst has gained widespread attention in recent years.•A comprehensive overview of the state-of-the-art techniques for the regeneration of a new catalyst and the recovery of valuable metals from the spent V2O5-WO3/TiO2 catalyst.•The advantages and challenges of various technologies are discussed in detail.