摘要:
The present invention provides novel solutions to the problem of recycling carbonylation catalysts in epoxide carbonylation processes. The inventive methods are characterized in that the catalyst is recovered in a form other than as active catalyst. In some embodiments, catalyst components are removed selectively from the carbonylation product stream in two or more processing steps. One or more of these separated catalyst components are then utilized to regenerate active catalyst which is utilized during another time interval to feed a continuous carbonylation reactor.
摘要:
To provide a method for treating a wastewater, which can efficiently collect a heavy metal compound from a wastewater containing the heavy metal compound derived from an aromatic carboxylic acid production process. A method for treating a wastewater comprising bringing a wastewater derived from an aromatic carboxylic acid production process into contact with a specific chelate resin to collect a heavy metal compound contained in the wastewater on the specific chelate resin.
摘要:
A method for recovering and reusing a ring-halogenation catalyst comprises: (A) Contacting an aromatic compound with chlorine or bromine in the presence of a catalyst composition, where the catalyst composition comprises at least one salt comprising a Group 4-13 metal, a lanthanide metal, or an actinide metal; and at least one organic counterion derived from an organic acid having a pKa relative to water of 0 or greater; and at least one organic sulfur compound; to form a first product mixture comprising a monochloro or a monobromo aromatic compound and a Group 4-13 metal halide, a lanthanide metal halide or an actinide metal halide; (B) Separating the metal halide from the first product mixture; and (C) Contacting at least a portion of the metal halide and an aromatic compound with chlorine or bromine, and at least one organic sulfur compound; to form a second product mixture comprising a monochloro or a monobromo aromatic compound and a Group 4-13 metal halide, a lanthanide metal halide or an actinide metal halide having a pKa relative to water of 0 or greater; and at least one organic sulfur compound.
摘要:
An apparatus and a method for effectively recovering acetic acid and catalyst from a mother liquor discharged from a series of processes including an oxidation process, a crystallization process and a solid-liquid separation process, in a continuous process for preparing naphthalenedicarboxylic acid by oxidizing dimethylnaphthalene in the presence of an oxygen-containing gas and an acetic acid solvent, using a catalyst system comprising a transition metal such as cobalt or manganese, and a bromine-based compound, are provided.
摘要:
The subject for the invention is to efficiently use, recover, and reuse a soluble metallic catalyst with great ease at low cost in various liquid-phase reactions using the soluble metallic catalyst. The invention provides a method of liquid-phase reaction using a soluble metallic catalyst in which the soluble metallic catalyst is caused to coexist with an anion-exchange resin during the reaction and the reaction is conducted under such conditions that 50% or more of the soluble metallic catalyst is adsorbed onto the anion-exchange resin. The anion-exchange resin having the soluble metallic catalyst adsorbed thereon is separated from the liquid reaction mixture to thereby recover the soluble metallic catalyst and reuse it in a liquid-phase reaction.