Catalytic process for making H2O2 from hydrogen and oxygen

Claim 1

A method of making hydrogen peroxide from hydrogen and oxygen in a reaction medium at superatmospheric pressures, characterized in that: (i) the oxygen and hydrogen are reacted in an aqueous reaction medium having substantially no organic component present; and (ii) as catalyst, is used a catalytically effective amount of Pd on adsorbent carbon in the weight ratio of Pd to Pd plus carbon of above about 0.5 percent.

Claim 2

A method of making hydrogen peroxide from hydrogen and oxygen in a reaction medium at superatmospheric pressures, characterized in that: (i) the oxygen and hydrogen are reacted in an aqueous reaction medium having substantially no organic component present; and (ii) as catalyst, is used a catalytically effective amount of Pd on adsorbent carbon in the weight ratio of Pd to Pd plus carbon of above about 0.5 percent.

Claim 5

A method as claimed in any preceding claim wherein the weight ratio of Pd to Pd plus carbon is above about 2 percent.

Claim 6

A method as claimed in any preceding claim wherein the reaction medium has a chloride ion concentration between about 0.01 and 2 M and a hydrogen ion concentration between about 0.01 and 2 M.

Claim 7

A method of making hydrogen peroxide from hydrogen and oxygen in a'reaction medium at superatmospheric pressures, characterized in that:- (i) an aqueous reaction medium having substantially no organic component present is used; and (ii) A catalytically effective amount of Pd on adsorbent carbon is used as catalyst, said catalyst being prepared in situ by adding a Pd salt solution and finely divided carbon to the H 2 0 2 reaction vessel or to a vessel interconnected with said reaction vessel, so that the resulting reaction mixture has a ratio of Pd to Pd plus carbon of above about 0.5 percent.

Claim 8

A method of making hydrogen peroxide from hydrogen and oxygen in a'reaction medium at superatmospheric pressures, characterized in that:- (i) an aqueous reaction medium having substantially no organic component present is used; and (ii) A catalytically effective amount of Pd on adsorbent carbon is used as catalyst, said catalyst being prepared in situ by adding a Pd salt solution and finely divided carbon to the H 2 0 2 reaction vessel or to a vessel interconnected with said reaction vessel, so that the resulting reaction mixture has a ratio of Pd to Pd plus carbon of above about 0.5 percent.