Preliminary results of metals leaching from a spent hydrodesulphurization (HDS) catalyst
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Wroclaw University of Technology
Władysława Mulak   

Wroclaw University of Technology, Chemical Department, Wybrzeże Wyspiańskiego 27, 50-370 Wroclaw, Poland
Publication date: 2006-01-01
Physicochem. Probl. Miner. Process. 2006;40(1):69–76
A spent industrial HDS catalyst Ni,Mo/γ−Al2O3 used for reducing sulphur in petroleum products was physically and chemically characterized by X-ray diffraction, scanning electron microscope, electron microprobe and chemical analysis. The leaching efficiency of Mo, Ni, V and Al from the spent catalyst in oxalic acid solution with hydrogen peroxide addition was investigated. The effects of oxalic acid and hydrogen peroxide concentrations and the stirring speed on the rate of metal leaching were studied. The results revealed that addition of hydrogen peroxide to oxalic acid up to 3.0M H2O2 concentration enhanced leaching of metals remarkably, and thereafter remained relatively constant. The highest extraction of metals from the spent catalyst (at 50oC in solution of 0.5M H2C2O4 with 3.0M H2O2) was found to be 90% Mo, 94% V, 65% Ni and 33% Al in 4 hour leaching.