The invention discloses a method for comprehensively recovering metallic
cobalt,
ruthenium and aluminum from a Fischer-Tropsch synthesis dead catalyst Co-Ru / Al2O3, and the method can be used for effectively separating and comprehensively recovering valuable metallic
cobalt,
ruthenium and aluminum from the Fischer-Tropsch synthesis dead catalyst Co-Ru / Al2O3. The method comprises the steps of: firstly carrying out
hydrocarbon removal and reductive treatment on the dead catalyst; effectively separating
cobalt slag in an alkali fusion step; and carrying out acid leaching on the cobalt
slag,
oxalate or
oxalate deposited cobalt, reducing cobalt
oxalate, dissolving the metallic cobalt via
nitric acid and the like to obtain Co(NO3)2.6H2O. Ruthenate is obtained by the steps of alkali fusion and deionized water leaching; and steps of
ethanol reduction, concentrated
hydrochloric acid dissolution, reduced pressure
distillation and the like are carried out on the ruthenate to obtain a beta-RuCl1.xH2O product which is high in purity. By using a CO2
carbon dioxide decomposition method, the parameters such as
reaction temperature, CO2 flow velocity, pH value of reaction destination and the like are controlled and aluminum
hydroxide is prepared from meta-
aluminate solution; high-temperature
calcination is carried out to obtain aluminum
oxide; and the product quality meets the quality requirement of first-
level aluminum oxide of
national standard and the process is economic and environment-friendly. According to the invention, the metallic
recovery rate is high, wherein the
recovery rate of cobalt is greater than or equal to 97%, the
recovery rate of
ruthenium is greater than or equal to 95% and the recovery rate of aluminum is greater than or equal to 92%.