| 摘要 |
A process for purifying a crude olefinically unsaturated nitrile containing hydrogen cyanide and water by feeding the crude olefinically unsaturated nitrile at a point above the middle of a rectifying column for stripping hydrogen cyanide, withdrawing and condensing a vapor of hydrogen cyanide from the top of the column while withdrawing the olefinically unsaturated nitrile and water from the bottom of the column, which process comprises withdrawing a vapor in the column at a point between the top of the column and the point of introduction of the crude olefinically unsaturated nitrile at a substantially constant rate, cooling and condensing the vapor withdrawn in a condenser having an outlet for non-condensing gas while continuously withdrawing non-condensing gas in the vapor from the condenser, and returning the condensate liquid to the column at an intermediate point between the point of introduction of the crude olefinically unsaturated nitrile and the top of the column, and a condenser useful for the above described process which comprises an heat exchange section having an inlet for vapor at its upper part and a liquid reservoir section having an outlet for condensate liquid at its lower part and an opening at the side wall of the liquid reservoir section, the opening being connected with a conduit for withdrawing non-condensing gas from the condenser. |
