Method for producing sodium thiosulfate by utilizing catalytic cracking flue gas desulfurization wastewater

The invention provides a method for producing sodium thiosulfate by utilizing catalytic cracking flue gas desulfurization wastewater, which sequentially comprises the following steps: S1, adding sodium thiosulfate and optional strong alkali into the catalytic cracking flue gas desulfurization wastewater for treatment, and filtering to obtain pretreated wastewater; s2, adsorbing and decolorizing the wastewater pretreated in the step S1 to obtain decolorized wastewater; s4, the pH value of the wastewater is controlled to be 9-12, sulfur is added for a sulfuration reaction, and sulfuration liquid containing sodium thiosulfate is prepared; and S5, evaporating, concentrating and crystallizing the vulcanized liquid obtained in the step S4 to obtain a sodium thiosulfate product. The desulfurization waste liquid waste is recycled, the desulfurization waste liquid is used for producing sodium thiosulfate with wide industrial application, the discharge amount of the desulfurization waste liquid is remarkably reduced, g