Chemistry of inorganic compounds – Oxygen or compound thereof – Peroxide
Reexamination Certificate
2007-10-30
2007-10-30
Langel, Wayne A. (Department: 1754)
Chemistry of inorganic compounds
Oxygen or compound thereof
Peroxide
C502S230000
Reexamination Certificate
active
11167573
ABSTRACT:
A method for improving drastically both the selectivity and yield of hydrogen peroxide in the direct oxidation of hydrogen to hydrogen peroxide over a solid catalyst comprising palladium, which comprises:i) depositing on the solid catalyst at least two halogen containing compounds, one compound essentially comprising bromine and second compound essentially comprising fluorine with the bromine to palladium and fluorine to palladium atom ratios in the range from 0.02 to 20 and from 0.01 to 50, respectively;ii) decomposing the halo compounds deposited on the solid catalyst by calcination at a temperature above 200° C. under inert, reducing or oxidizing gas atmosphere or under vacuum; andiii) contacting the solid catalyst obtained from step (ii) with a gas mixture consisting of hydrogen and oxygen or air or O2enriched air in an aqueous reaction medium, comprising a mineral acid at the following reaction conditions: concentration of mineral acid in the reaction medium above 0.001 mol/dm3, concentration of the solid catalyst in the reaction medium above 0.01 g/dm3, H2/O2mole ratio in the gas mixture in the range from 0.01 to 10, flow rate of the gas mixture in the range from 50 cm3/g catalyst/h to 50,000 cm3/g catalyst/h, gas pressure at least 0.9 atm, and temperature below 100° C. and contact period of the reaction medium at least 0.01 h, is disclosed.
REFERENCES:
patent: 4256608 (1981-03-01), Antos
patent: 5922639 (1999-07-01), Alario et al.
patent: 5965101 (1999-10-01), Goto et al.
patent: 6117409 (2000-09-01), Bertsch-Frank et al.
patent: 6218334 (2001-04-01), Alario et al.
patent: 2001/0024634 (2001-09-01), Bertsch-Frank et al.
Drastic increase of selectivity for H2O2formation in direct oxidation of H2to H2O2over supported Pd catalysts due to their bromination; Chem Comm 2004, 2054-2055; Choudhary, Samanta, Giakwad, no month.
Choudhary Vasant Ramchandra
Jana Prabhas
Samanta Chancal
Council Of Scientific And Industrial Research
Ladas & Parry LLC
Langel Wayne A.
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