Facile synthesis of W–Mo bimetallic oxides with high adsorption properties from secondary resources

A simple solvothermal method was used to obtain W–Mo bimetallic oxides from W–Mo alloy scrap, and pure metal powders were also used as the raw materials to simulate scrap. The products had a sea urchin-like structure with abundant oxygen vacancies and the products prepared at low temperatures forms a sosoloid resembling orthorhombic W_0.4Mo_0.6O₃. The W–Mo bimetallic oxide prepared at the reaction temperature of 120 °C exhibited excellent selective adsorption performance for methylene blue (MB), which the adsorption rate of MB reached 99% in 12 min and the adsorption rate reached 90% after 6 adsorption cycles. When the W–Mo molar ratio is 1:3, the maximum adsorption capacity of sample for MB can reach 1148 mg‧g⁻¹. The adsorption process followed the Langmuir and pseudo-second-order models, which is surface-controlled monolayer adsorption. The experimental results show the feasibility of preparing W–Mo bimetal oxide products from pure materials and scrap. The process is simple and effective, which offered a potential approach for secondary resource recycling and reusing.