Hydroxylation and sulfidation for nickel recovery from a spent catalyst containing the chelating agent, 2,2'-bipyridine.

ABSTRACT: Techniques for recovering nickel (Ni) from various Ni-containing products are needed for resource circulation. In this study, Ni recovery from a spent catalyst containing 2,2'-bipyridine (bpy) was conducted by precipitation using hydroxylation and sulfidation. In the absence of bpy, both methods completely precipitated Ni as estimated in chemical equilibrium calculations. For an actual spent catalyst with a bpy/Ni molar ratio of one, the recovery rates were reduced to approximately 70% and 90% for the hydroxylation and sulfidation methods, respectively. Similar values were obtained for a simulated spent catalyst with a bpy/Ni molar ratio of one. Precipitation was inhibited in both methods for simulated spent catalyst with an initial bpy/Ni molar ratio of three. Ultraviolet-visible spectros

SUBMITTER: Iwai H 

PROVIDER: S-EPMC11894522 | biostudies-literature | 2025 Mar

REPOSITORIES: biostudies-literature