Process for preparing zinc oxide-based sorbents

A process for preparing fluidizable, attrition resistant sorbent particles, comprising:

• providing an aqueous slurry of a precipitated zinc oxide precursor and a precipitated aluminum oxide precursor, the zinc oxide precursor and the aluminum oxide precursor being selected such that a mixture of the precursors can be converted to zinc oxide and zinc aluminate;
• adjusting the pH of the aqueous slurry to a pH of less than 4.5;
• spray drying the aqueous slurry to form spray dried particles comprising a mixture of the zinc oxide precursor and the aluminum oxide precursor;
• and
• calcining the zinc oxide precursor and the aluminum oxide precursor in the spray dried particles to zinc oxide and zinc aluminate to form fluidizable sorbent particles comprising a two phase active zinc component comprising a zinc oxide phase and a zinc aluminate phase.

A process for preparing fluidizable, attrition resistant sorbent particles, comprising:

• providing an aqueous solution of a zinc oxide precursor and an aluminum oxide precursor, the zinc oxide precursor and the aluminum oxide precursor being selected such that a mixture of the precursors can be converted to zinc oxide and zinc aluminate;
• coprecipitating the zinc oxide precursor and the aluminum oxide precursor to form an aqueous slurry of a precipitated zinc oxide precursor and a precipitated aluminum oxide precursor;
• adjusting the pH of the aqueous slurry to a pH of less than 4.5;
• spray drying the aqueous slurry to form spray dried particles comprising a mixture of the zinc oxide precursor and the aluminum oxide precursor;
• and
• calcining the zinc oxide precursor and the aluminum oxide precursor in the spray dried particles to zinc oxide and zinc aluminate to form fluidizable sorbent particles comprising a two phase active zinc component comprising a zinc oxide phase and a zinc aluminate phase, wherein the calcining temperature is at least about 500° C.