title: Nickel recovery from spent nickel catalyst.
abstract: A process for nickel recovery from a spent catalyst of definite composition has been developed using the hydro-metallurgical route. The processing steps includes direct sulphuric acid leaching followed by separation of iron as well as silica and other impurities. For a 152 microm particle size catalyst, extraction of about 98% nickel was achieved at 363 K in 2 h using a sulphuric acid concentration (v/v) of 8% and a pulp density of 10%. The dissolution of nickel followed diffusion-controlled leaching kinetics. Increase in temperature and sulphuric acid concentration resulted in increase in the nickel recovery. The activation energy for nickel dissolution was calculated to be 62.8 kJ mol(-1). Finally, nickel was recovered as value-added products such as sulphide and oxalate with overall recovery of 90 and 88% of nickel, respectively.
authors.affiliation: National Metallurgical Laboratory, Jamshedpur, India. drkksahu@yahoo.com
authors.forename: Kamala K
authors.initials: KK
authors.lastname: Sahu
authors.forename: Archana
authors.initials: A
authors.lastname: Agarwal
authors.forename: Banshi D
authors.initials: BD
authors.lastname: Pandey
mesh_terms: D002384:Catalysis; D002617:Chemical Industry; D011232:Chemical Precipitation; D003247:Conservation of Natural Resources; D005308:Fertilizers; D007501:Iron / Q000737:chemistry; D009532:Nickel / Q000737:chemistry / Q000302:isolation & purification*; D010070:Oxalates / Q000737:chemistry; D012822:Silicon Dioxide / Q000737:chemistry; D013464:Sulfuric Acids / Q000737:chemistry
chemical_list: D005308:Fertilizers; D010070:Oxalates; D013464:Sulfuric Acids; D012822:Silicon Dioxide; D009532:Nickel; D007501:Iron; C017558:nickel sulfide; C033158:sulfuric acid