摘要
A process for separating ethylene glycol, which is synthesizedfrom syngas, has been developed by the ChinaWuhuan Engineering Company, Ltd. This process coversthe following procedures. The hydrogenate obtainedfrom hydrogenation of dimethyl oxalate is subjected topretreatment involving the recovery of methanol, dehydration,removal of esters of oxalic acid, rectification andrefining to obtain the ethylene glycol product. Dibutylketone used as the azeotropic agent is mixed with theraw ethylene glycol obtained after recovery of methanol,dehydration, and removal of oxalic esters to give the EGdimerizationreaction to convert the remaining cyclopentadieneinto dicyclopentadiene with the remainder undergoingseparation via rectification to extract the remainingisoprene which is concentrated in the tower overhead,while dicyclopentadiene and piperylene are concentrated inthe tower kettle. The isoprene material obtained in the previousphase is further subjected to extractive rectificationand purification to yield the polymerization grade isoprene.The advantage of this method is to effectively inhibit theco-polymerization of isoprene and cyclopentadiene in thecourse of heating and separation to significantly reducethe loss of isoprene and cyclopentadiene.rich azeotrope, which is then subjected to condensationand separation to yield an azeotrope-rich liquid phase andan EG-rich liquid phase. The EG-rich liquid phase is furtherrefined to give a premium EG and an on-spec EG.
A process for separating ethylene glycol, which is synthesizedfrom syngas, has been developed by the ChinaWuhuan Engineering Company, Ltd. This process coversthe following procedures. The hydrogenate obtainedfrom hydrogenation of dimethyl oxalate is subjected topretreatment involving the recovery of methanol, dehydration,removal of esters of oxalic acid, rectification andrefining to obtain the ethylene glycol product. Dibutylketone used as the azeotropic agent is mixed with theraw ethylene glycol obtained after recovery of methanol,dehydration, and removal of oxalic esters to give the EGdimerizationreaction to convert the remaining cyclopentadieneinto dicyclopentadiene with the remainder undergoingseparation via rectification to extract the remainingisoprene which is concentrated in the tower overhead,while dicyclopentadiene and piperylene are concentrated inthe tower kettle. The isoprene material obtained in the previousphase is further subjected to extractive rectificationand purification to yield the polymerization grade isoprene.The advantage of this method is to effectively inhibit theco-polymerization of isoprene and cyclopentadiene in thecourse of heating and separation to significantly reducethe loss of isoprene and cyclopentadiene.rich azeotrope, which is then subjected to condensationand separation to yield an azeotrope-rich liquid phase andan EG-rich liquid phase. The EG-rich liquid phase is furtherrefined to give a premium EG and an on-spec EG.
