Heavy metal-manganese oxidation catalysts and process of producing same

Claim 2

The process of producing a heavy metal-manganese dioxide oxidation catalyst comprising the steps of: (a) forming a suspension of finely-divided alkali metal delta manganese dioxide hydrate in an aqueous solution containing heavy metal ions selected from the class consisting of copper, chromium, iron, lead, nickel, cobalt, silver, and mixtures thereof, said suspension having an initial pH of at least one-half pH point below the pH at which the heavy metal hydroxide begins to precipitate; (b) exchanging the alkali of said alkali metal manganese dioxide hydrate with said heavy metal ions under pH conditions on the acid side of said hydroxide precipitation pH and continuing said exchanging reaction until the manganese reaction product contains not over 0.05 moles of bound alkali metal per mole of manganese, said heavy metal ions exchanged for said alkali metal being complexed with the manganese dioxide of the resulting reaction product; (c) separating said reaction product from said aqueous solution; and (d) preparing dried porous catalytic pellets from said reaction product.

Claim 3

The process of claim 1 in which said manganese dioxide is by-product manganese dioxide containing sodium and potassium.

Claim 4

The process of claim 1 or claim 2 in which said heavy metal ions are copper ions.

Claim 5

The process of claim 1 in which said heavy metal ions are lead ions.

Claim 6

The process of claim 1 or claim 2 in which said heavy metal ions are iron ions.

Claim 7

The process of claim 1 or claim 2 in which said heavy metal ions are chromium ions.

Claim 8

The process of claim 1 in which said reaction is continued until said reaction product contains not over 0.03 moles of alkali metal per mole of manganese, and in which said heavy metal ions are selected from the group consisting of copper, lead, iron, and silver.

Claim 9

The process of claim 1 in which said catalytic pellets are prepared from a paste comprising a mixture of said reaction product in hydrated form and water-containing bentonite, said paste being extruded to form pellets, and said pellets being dried to a porous non-agglomerating condition.

Claim 10

The process of claim 1 in which said catalytic pellets are prepared from a paste comprising a mixture of said reaction product in hydrated form and a partially peptized hydrated alumina catalyst carrier, said pellets being dried to remove water therefrom.

Claim 11

The process of producing a heavy metal-manganese dioxide oxidation catalyst, consisting essentially of the steps of: (a) introducing finely-divided alkali metal delta manganese dioxide hydrate into an aqueous solution of heavy metal ions to form a reaction suspension, said heavy metal ions being selected from the class consisting of copper, iron, lead, nickel, cobalt, chromium, and mixtures thereof, said suspension having an initial pH of at least one-half pH point below the pH at which the heavy metal hydroxide begins to precipitate; (b) exchanging the alkali metal of said alkali metal manganese dioxide hydrate in said suspension with said heavy metal ions under pH conditions on the acid side of said hydroxide precipitation pH and continuing said exchanging reaction until the reaction product contains not over 0.03 moles of total bound potassium and sodium per mole of manganese, said heavy metal ions exchanged for said alkali metal being complexed with the manganese dioxide of the resulting reaction product; (c) separating said reaction product from said aqueous solution; and (d) preparing dried porous catalytic pellets from said reaction product by forming a paste from a mixture of said reaction product with water and a binder, extruding said paste to form pellets, and drying said pellets to remove water therefrom.

Claim 12

The process of producing a heavy metal-manganese dioxide oxidation catalyst, consisting essentially of the steps of: (a) introducing finely-divided alkali metal delta manganese dioxide hydrate into an aqueous solution of heavy metal ions to form a reaction suspension, said heavy metal ions being selected from the class consisting of copper, iron, lead, nickel, cobalt, chromium, and mixtures thereof, said suspension having an initial pH of at least one-half pH point below the pH at which the heavy metal hydroxide begins to precipitate; (b) exchanging the alkali metal of said alkali metal manganese dioxide hydrate in said suspension with said heavy metal ions under pH conditions on the acid side of said hydroxide precipitation pH and continuing said exchanging reaction until the reaction product contains not over 0.03 moles of total bound potassium and sodium per mole of manganese, said heavy metal ions exchanged for said alkali metal being complexed with the manganese dioxide of the resulting reaction product; (c) separating said reaction product from said aqueous solution; and (d) preparing dried porous catalytic pellets from said reaction product by forming a paste from a mixture of said reaction product with water and a binder, extruding said paste to form pellets, and drying said pellets to remove water therefrom.

Claim 13

The catalytic pellets produced by the process of claim 10.

Claim 14

The process of claim 10 in which said heavy metal ions are copper ions.

Claim 15

The process of claim 10 in which said heavy metal ions are lead ions.

Claim 16

The process of claim 10 in which said heavy metal ions are chromium ions.

Claim 17

The process of claim 10 in which said heavy metal ions are iron ions.

Claim 18

The process of claim 1 or claim 10 in which said reaction is carried out at a pH of about 4.0 or higher.

Claim 19

The process of claim 10 in which said catalytic pellets are prepared from a mixture of said reaction product in hydrated form and a partially peptized hydrated alumina carrier, said pellets after extrusion being dried to remove water.

Claim 20

The catalytic pellets produced by the process of claim 17.

Claim 21

The catalytic pellets of claim 11 in which said heavy metal ions are copper ions.

Claim 22

The catalytic pellets of claim 11 in which said heavy metal ions are lead ions.

Claim 23

The catalytic pellets of claim 11 in which said heavy metal ions are chromium ions.

Claim 24

The catalytic pellets of claim 11 in which said heavy metal ions are iron ions.