Abstract: A process for separating ethylene glycol and 1,2-butanediol. A material flow containing ethylene glycol and 1,2-butanediol gets into the lower-middle part of the azeotropic rectification column C3 after the light components are removed by the separating columns C1 and C2, wherein the ethylene glycol and the azeotropic agent added from the top of the column form azeotrope which is distilled out from the top of the column and gets into the phase separator D1 after being condensed, the upper phase enriched with azeotropic agent after the phase was separated returns to the top of the column to continue to participate in azeotropy, and the lower phase enriched with ethylene glycol gets into the fourth separating column C4 to be refined to obtain the ethylene glycol product.

Abstract: The present invention relates to a process for separating ethylene glycol and 1,2-butanediol. A material flow containing ethylene glycol and 1,2-butanediol gets into the lower-middle part of the azeotropic rectification column C3 after the light components are removed by the separating columns C1 and C2, wherein the ethylene glycol and the azeotropic agent added from the top of the column form azeotrope which is distilled out from the top of the column and gets into the phase separator D1 after being condensed, the upper phase enriched with azeotropic agent after the phase was separated returns to the top of the column to continue to participate in azeotropy, and the lower phase enriched with ethylene glycol gets into the fourth separating column C4 to be refined to obtain the ethylene glycol product.

Abstract: Provided is a process for crystallization separating p-xylene, comprising: a) feeding a mixed xylenes stream comprising greater than or equal to 60% by weight, of p-xylene, such as 60% to 98% by weight of p-xylene, to a crystallization unit to perform cooling crystallization, to obtain a slurry comprising p-xylene crystals; and b) feeding the slurry to a filtration and purification unit, to obtain a mother liquor, washings, and p-xylene, wherein the filtration and purification unit uses a simulated moving bed or a combination of multiple moving beds.

Abstract: Provided is a process for crystallization separating p-xylene, comprising: a) feeding a mixed xylenes stream comprising greater than or equal to 60% by weight, of p-xylene, such as 60% to 98% by weight of p-xylene, to a crystallization unit to perform cooling crystallization, to obtain a slurry comprising p-xylene crystals; and b) feeding the slurry to a filtration and purification unit, to obtain a mother liquor, washings, and p-xylene, wherein the filtration and purification unit uses a simulated moving bed or a combination of multiple moving beds.