摘要:
Disclosed is a process and apparatus for treating a purge stream in a carboxylic acid production process. The process employs a purge process that allows for the separation of oxidation byproducts into benzoic acid and non-benzoic acid oxidation byproducts, thus providing flexibility in the treatment and use of such oxidation byproducts.
摘要:
Catalytic processes for the conversion of 2,5-dimethyl furan (DMF) to para-xylene are described. Para-xylene is a key product that is currently obtained commercially from petroleum sources. However, it has now been determined that the cycloaddition of ethylene to DMF provides an alternative route to para-xylene. Advantageously, the DMF starting material for the processes may be synthesized from carbohydrates (e.g., glucose or fructose), thereby providing a pathway that relies at least partly, if not completely, on renewable feedstocks.
摘要:
To provide a solid catalyst containing a cyclic imide skeleton which is easily available and easily separable from reaction products and which is easily recovered and regenerated, and free from reaction inhibitory factors; and a process for oxidation of organic compounds with the solid catalyst.An immobilized cyclic imide catalyst having a structure represented by following Formula (1), wherein X is oxygen or an —OR group (wherein R is hydrogen atom or a hydroxyl-protecting group); n is 0 or 1; Z1 is a five- or six-membered cyclic imide skeleton to which an aromatic or nonaromatic ring Z2 may be adjacent; elliptically shaped moiety S is an inorganic support; A1 is a group linking silicon atom with the cyclic imide skeleton Z1 or with the ring Z2 and is either a divalent hydrocarbon group or a group composed of a divalent hydrocarbon group and an amide bond (—NHCO—); and the cyclic imide skeleton Z1 and the ring Z2 may each be substituted.
摘要:
Disclosed are processes and apparatus for producing a carboxylic acid. The processes employ a concentration section disposed before and/or after a product isolation section, which allows for oxidation byproducts produced in the process to exit the product isolation section with the isolated carboxylic acid product and/or to be combined with the isolated carboxylic acid product downstream of the product isolation section at a rate of at least about 15 percent of the net make rate of the oxidation byproducts in the production process.
摘要:
An integrated process for producing aromatic hydrocarbons and ethylene and/or propylene and optionally other lower olefins from low molecular weight hydrocarbons, preferably methane, which comprises: (a) contacting one or more low molecular weight alkanes, preferably methane, with a halogen, preferably bromine, under process conditions sufficient to produce a monohaloalkane, preferably monobromomethane, (b) reacting a first portion of the monohaloalkane in the presence of a coupling catalyst under process conditions sufficient to produce aromatic hydrocarbons and C2-5 alkanes, (c) separating the aromatic hydrocarbons from the product mixture of step (b) to produce aromatic hydrocarbons, (d) reacting a second portion of the monohaloalkane in the presence of a coupling catalyst under process conditions sufficient to produce ethylene and/or propylene.
摘要:
Disclosed is an optimized system for more efficiently and economically producing terephthalic acid. The system employs an evaporative removal step downstream of oxidative digestion. The evaporative removal step removes a portion of the liquid phase and promotes precipitation of certain aromatic impurities. By promoting precipitation of certain aromatic impurities, the amount of the precipitated impurities in the recycled solvent is advantageously reduced.
摘要:
Disclosed is an optimized process and apparatus for more efficiently and economically carrying out the liquid-phase oxidation of an oxidizable compound. Such liquid-phase oxidation is carried out in a bubble column reactor that provides for a highly efficient reaction at relatively low temperatures. When the oxidized compound is para-xylene and the product from the oxidation reaction is crude terephthalic acid (CTA), such CTA product can be purified and separated by more economical techniques than could be employed if the CTA were formed by a conventional high-temperature oxidation process.
摘要:
The invention provides improved energy content in and shaft power recovery from off-gas from xylene oxidation reactions while at the same time minimizing wastewater treatment cost. More shaft power is produced using off-gas than is required to drive the main air compressor, even with preferred, relatively low oxidation temperatures. Simultaneously, an amount of wastewater greater than byproduct water from oxidation of xylene is kept in vapor form and treated along with off-gas pollutants in a self-sustaining (self-fueling) gas-phase thermal oxidative destruction unit. Optionally, off-gas is combined from multiple xylene oxidation reactors, comprising primary and/or secondary oxidation reactors and forming TPA and/or IPA. Optionally, air compressor condensate and caustic scrubber blowdown are used in a TPA process or as utility water, effectively eliminating normal flow of liquid wastewater effluent from a TPA plant. Optionally, PET off-gas containing the water of PET formation is treated in a shared thermal oxidative destruction unit, effectively eliminating normal flow of liquid wastewater effluent from a combined pX-to-TPA-to-PET plant.
摘要:
Disclosed is an optimized process and apparatus for more efficiently and economically carrying out the liquid-phase oxidation of an oxidizable compound. Such liquid-phase oxidation is carried out in a bubble column reactor that provides for a highly efficient reaction at relatively low temperatures. When the oxidized compound is para-xylene and the product from the oxidation reaction is crude terephthalic acid (CTA), such CTA product can be purified and separated by more economical techniques than could be employed if the CTA were formed by a conventional high-temperature oxidation process.
摘要:
Disclosed is an optimized process and apparatus for more efficiently and economically carrying out the liquid-phase oxidation of an oxidizable compound. Such liquid-phase oxidation is carried out in a bubble column reactor that provides for a highly efficient reaction at relatively low temperatures. When the oxidized compound is para-xylene and the product from the oxidation reaction is crude terephthalic acid (CTA), such CTA product can be purified and separated by more economical techniques than could be employed if the CTA were formed by a conventional high-temperature oxidation process.