SEPARATION OF M-XYLENE

摘要

PURPOSE:To obtain high-purity m-xylene from a 8C aromatic compound mixture by a combination of chromatography and distillation. CONSTITUTION:A mixture of 8C aromatic compounds is charged together with toluene used as a desorbent to a chromatographic separation apparatus 1 containing zeolite as an adsorbent and the mixture is separated into a m-xylene fraction and a non-m-xylene fraction. Each fraction is distilled to obtain toluene and a 8C fraction and toluene is recycled and reused. Toluene replenished from an external source is distilled (3) together with the non-m-xylene fraction to remove the accompanying 8C component and supplied to the chromatographic separation apparatus as a desorbent. The process is effective for preventing the contamination of m-xylene fraction with 8C component accompanying to the replenishing toluene.