Method of regenerating a degraded working solution for the production of hydrogen peroxide
Abstract
Abstract A working solution comprising anthraquinone and its derivatives, used for the production of hydrogen peroxide on becoming degraded by formation of non-effective anthraquinone is generated by an auto-oxidation process employing anthraquinone, which comprises: Contacting, at a temperature of below 130°C., and in the presence of a catalyst comprising a metal selected from a platinum group and supported on a carrier, said degraded working solution, which comprises non-effective anthraquinone and tetrahydroanthraquinone with an olefinic compound whose hydrogenation product is gaseous at said contact temperature and Subsequently, contacting the thus treated working solution, at a temperature above 130°C., and in the presence of a catalyst comprising a metal selected from the platinum group and supported on a carrier, with an olefinic compound whose hydrogenation product is gaseous at said contact temperature, Said method being characterized by the fact that at a temperature below 130°C., the regeneration of non-effective anthraquinone is accelerated much faster than the dehydrogenation reaction of tetrahydroquinone and therefore, at a pont in time, when all non-effective anthraquinone has been converted to anthraquinone, the temperature can be raised above 130°C. to permit dehydrogenation of said tetrahydroanthraquinone without incurring any impedance of the dehydrogenation reaction.
Inventors
- 👤 Hiroshi Shin
- 👤 Junichiro Sugano
- 👤 Tadashi Yoshii
- 👤 Kichiro Iwamoto
- 👤 Yasuhisa Kuriyama
- 👤 Minoru Kakuda
Bibliographic Details
Claims Analysis
Total Claims: 5References Cited (Backward Citations)
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