過マンガン酸塩還元性化合物を除去することによって酢酸流を精製する方法

摘要

Processes for the reduction and/or removal of permanganate reducing compounds (PRC'S) formed by the carbonylation of methanol in the presence of a Group VIII metal carbonylation catalyst to produce acetic acid are disclosed. More specifically, processes for reducing and/or removing PRC's or their precursors from intermediate streams during the formation of acetic acid by said carbonylation processes are disclosed. In particular, processes in which a low boiling overhead vapor stream from a light ends column is subjected to a distillation to obtain an overhead that is subjected to an extraction to selectively remove and/or reduce PRC's from the process is disclosed. The processes include steps of recycling one or more return streams derived from the distillation step and/or the extraction step to a light ends column and/or a drying column in order to improve water control in the overall reaction system.