Abstract:
Production of very pure butanediol-1,4 by separating in column 1 crude butanediol into a fraction A containing butanediol and lower boiling components and a fraction B containing higher boiling components, separating fraction A in column 2 into an overhead and a bottoms product consisting of very pure butanediol and separating fraction B in column 3 into butanediol of lower purity and components of higher boiling point.
Abstract:
AN IMPROVED PROCESS FOR THE PRODUCTION OF PURE 2-ETHYL HEXANOL (OBTAINED BY HYDROGENATION OF 2-ETHYLHEXEN-2-AL1) BY CONTINUOUS DISTILLATON IN THREE COLUMNS CONNECTED IN CASCADED FASHION THE IMPURITIES BOILING BELOW 2-ETHYL HEXANOL BEING TAKEN OVERHEAD IN THE FIRST COLUMN, PURE 2ETHYL HEXANOL BEING OVERHEAD IN THE SECOND COLUMN AND THE 2-ETHYL STILL REMAINING IN THE HIGHERBOILING IMPURITIES BEING SEPARATED IN THE THIRD COLUMN, THE IMPROVEMENT COMPRISING THE USE OF A PRESSURE OF FROM 200 TO 800 MM. OF HG AT THE HEAD OF THE SECOND COLUMN AND OF A PRESSURE OF FROM 70 TO 300 MM. OF HG AT THE HEAD OF THE THIRD COLUMN, SUFFICIENT 2-ETHYL HEXANOL BEING LEFT IN THE BOTTOMS OF THE SECOND COLUMN TO MAKE THE CONCENTRATION THEREOF AT LEAST 50%. 2-ETHYL HEXANOL IS USED IN THE MANUFACTURE OF PLASTICIZERS FOR POLYVINYL CHLORIDE.