| 摘要 |
The present invention relates to a separation process for removing acetone from a mixture comprising acetone, methyl acetate, methyl iodide and acetic acid, and in particular to a process for the removal of acetone from a stream comprising acetone, methyl acetate and methyl iodide, which stream has been obtained from a production system in which a mixture comprising methanol, methyl acetate and water is carbonylated to produce acetic anhydride and acetic acid, and said process comprising the steps of:
(a) introducing said stream comprising acetone, methyl acetate and methyl iodide into a first distillation zone;
(b) introducing acetic acid into said first distillation zone, either by addition of acetic acid to said stream comprising acetone, methyl acetate and methyl iodide or by introduction of acetic acid directly to the first distillation zone at one or more points at or above the point of introduction of said stream comprising acetone, methyl acetate and methyl iodide into the first distillation zone in step (a), or a combination of both;
(c) removing from the first distillation zone an overhead stream comprising methyl iodide and a bottoms stream comprising acetone, methyl acetate, acetic acid, and a reduced amount of methyl iodide;
(d) introducing into a second distillation zone the bottoms stream from step (c);
(e) removing from the second distillation zone an overhead stream comprising methyl acetate and methyl iodide and a bottoms stream comprising acetone, methyl acetate and acetic acid;
(f) introducing the bottoms stream from step (e) into a third distillation zone; and
(g) removing from the third distillation zone an overhead stream comprising methyl acetate and acetone and a bottoms stream comprising methyl acetate and acetic acid. |
