Method for the preparation of terephthalic acid
Abstract
Abstract AN APPARATUS FOR CONTINUOUS PRODUCTION OF TEREPHTHALIC ACID FROM P-DIALKYLBENZENE AND MOLECULAR OXYGEN WITH HIGH UTILIZATION RATIO OF SAID OXYGEN, WHICH COMPRISES A REACTOR WITH ITS BOTTOM TAPERED DOWNWARDS, THE REACTOR BEING PROVIDED WITH A GAS EXHAUST PIPE AT AN UPPER PART, AN EXIT FOR THE REACTION PRODUCT AT THE BOTTOM PORTION, AND A STARTING MATERIAL FEED PIPE AT A SUITABLE POSITION THEREBETWEEN; A GAS SPARGER FOR SUPPLYING MOLECULAR OXYGEN WHICH OPENS INTO THE REACTOR AT THE BOTTOM PORTION; A DRAFT TUBE WITH OPEN TOP AND BOTTOM, WHICH IS POSITIONED ABOVE THE GAS SPARGER; AND A GAS DISTRIBUTOR FOR DISPERSING THE MOLECULAR OXYGEN INTO THE REACTOR, WHICH IS POSITIONED ABOVE AND APPROPRIATELY SPACED FROM THE DRAFT TUBE; FURTHERMORE THE REACTOR BEING PROVIDED WITH A HEATING AND/OR COOLING MEANS FOR MAINTAINING THE REACTION MATERIAL IN THE REACTOR AT A TEMPERATURE OF 80-150*C.; WHEREBY P-DIALKYLBENZENE, AN ALIPHATIC MONO-CARBOXYLIC ACID AND A HEAVY METAL CATALYST, ARE SUPPLIED FROM THE STARTING MATERIAL FEED PIPE, AND AT LEAST A PART OF THE MOLECULAR OXYGEN IS SUPPLIED FROM THE GAS SPARGER.
Inventors
- 👤 Yataro Ichikawa
- 👤 Gentaro Yamashita
- 👤 Yuichi Akachi
Bibliographic Details
Claims Analysis
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