| abstract |
The present invention relates to a method for producing ethylene glycol and/or ethylene carbonate, the method comprising: Contacting at least a portion of the recycle gas stream comprising alkyl iodide impurities with a guard bed system located upstream of the ethylene oxide reactor to produce a treated recycle gas stream, the guard bed system depositing silver on the alumina. Comprising a guard layer material comprising; Contacting an epoxidation feed stream comprising an ethylene feed stream, oxygen, a chloride modifier and at least a portion of a treated recycle gas stream with an epoxidation catalyst in an ethylene oxide reactor to produce an epoxidation reaction product comprising ethylene oxide; And Product stream comprising ethylene carbonate and/or ethylene glycol and alkyl iodide impurities by contacting at least a portion of the epoxidation reaction product comprising ethylene oxide with a liquid absorbent in the presence of an iodide-containing catalyst in an absorber. Generating a recycle gas stream comprising a Including, The epoxidation feed stream comprising the ethylene feed stream, oxygen, modifier compound, and treated recycle gas stream contacted with the epoxidation catalyst in the ethylene oxide reactor comprises 8000 ppmv or less of ethane, The vinyl chloride modifier is added to the epoxidation feed stream, and the concentration of the vinyl chloride modifier added to the epoxidation feed stream represents the relative amount of chloride modifier species present in the epoxidation feed stream and is defined as The I-factor is controlled to range from 0.02 to 0.4: Factor I = ([vinyl chloride]+[ethyl chloride]+[methyl chloride]/3)/([ethylene]+70*[ethane]). |