Abstract: A method for preparing self-doped titanium-niobium oxide negative electrode material using a waste titanium dioxide carrier includes preparing self-doped TiNb2O7 negative electrode material for lithium-ion battery by using waste titanium dioxide carrier comprises the following steps: S1. converting a waste titanium dioxide carrier into TiO2 powder with the Ti content of ?95% and the Al content of 0.1-4.0%, based on the weight of oxide, respectively; and S2. mixing the TiO2 powder and Nb2O5 powder to form a mixture, roasting the mixture, and collecting the generated Al self-doped TiNb2O7, so as to obtain the self-doped TiNb2O7 negative electrode material. According to the method disclosed by the present invention, impurities represented by TiO2 and Al2O3 in the waste titanium dioxide carrier can be directly recycled, a self-doped TiNb2O7 (titanium niobium oxide) negative electrode material.

Abstract: A method for preparing molybdenum-based self-doped lithium-ion battery negative electrode material from molybdenum-containing waste catalyst includes: (1) calcinating and mechanically activating a waste hydrogenation catalyst containing molybdenum trioxide and aluminum oxide to obtain an oil-free and carbon-free micron-sized waste catalyst powder; (2) mixing the waste catalyst powder with sodium carbonate to obtain a mixture, and subjecting the mixture to thermal treatment to selectively convert molybdenum trioxide in the waste catalyst into sodium molybdate to obtain a clinker; (3) subjecting the clinker to leaching with water being used as a leaching agent, and collecting a leaching solution; and (4) mixing the leaching solution with a solution of a polyol containing a ferrous salt, subjecting the resulting mixture to a hydrothermal reaction, and collecting produced self-Al-doped ferrous molybdate to obtain the molybdenum-based self-doped lithium-ion battery negative electrode material.

Abstract: A method includes 1) removal oil from aluminum-based platinum rhenium-containing spent catalysts; 2) mixing the spent catalyst and sodium hydroxide powder and heating in an oxygen-free environment to obtain a clinker; 3) leaching the clinker in a weakly alkaline aqueous solution to obtain a first leach solution containing the elements Al and Re and a first leach residue containing Pt and Re; 4) converting the first leaching solution into a sodium meta-aluminate solution and a sodium perrhenate solution; 5) adding an aqueous solution of an acidic reagent and an aqueous solution of an oxidizing reagent to the first leaching residue for oxidizing acid leaching to obtain a second leaching solution containing precursors including platinum and rhenium; 6) reducing and loading the precursors on a carbon carrier to obtain the modified platinum based catalyst for fuel cell. The method enables the recovery of Re and Al elements from spent catalysts.