Process for the production of vinyl esters

Abstract

Abstract IMPROVEMENT IN A PROCESS FOR THE PRODUCTION OF VINYL ESTERS BY REACTING ETHYLENE, LOWER CARBOXYLIC ACIDS WITH 2 TO 4 CARBON ATOMS AND OXYGEN IN THE GAS PHASE AT ELEVATED TEMPERATURE AND NORMAL OR ELEVATED PRESSURE, IN THE PRESENCE OF SUPPORTED CATALYST CONSISTING ESSENTIALLY OF PALLADIUM, GOLD AND AN ALKALI METAL ACETATE ON A SILICIC ACID SUPPORT, WHICH IMPROVEMENT COMPRISES PREPARING THE CATALYST BY TREATING THE SUPPORT, SIMULTANEOUSLY OR SUCCESSIVELY OR IN COMBINATION WITH A SOLUTION A DND A SOLUTION B, THE SOLUTION A CONTAINING DISSOLVED SALTS OF PALLADIUM AND GOLD AND THE SOLUTION B CONTAINING COMPOUNDS WHICH ARE ABLE TO REACT ON THE CATALYST SUPPORT WITH THE NOBLE METAL SALTS OF THE SOLUTION A TO FORM WATER-IN-SOLUBLE NOBLE METAL COMPOUNDS WHICH ARE SUBSTANTIALLY FREE OF HALOGEN, SULPHUR AND NITROGEN, IMPREGNATING THE CATALYST SUPPORT WITH THE SOLUTIONS A AND B IR WITH THE COMBINED SOLUTION OF A AND B IN QUANITIES WHICH CORRESPOND TO FROM 1 TO 110% OF THE ABSORPTIVE CAPACITY OF THE CATALYST SUPPORT FOR THESE SOLUTIONS: SUBJECTING THE CATALYST SUPPORT IMPREGNATED WITH THE SOLUTIONS A AND B TO A TIME/ TEMPERATURE-TREATMENT WHICH IS SUCH THAT 95% AT LEAST OF THE IMTHE IMPREGNATED PALLADIUM AND 95% AT LEAST OF THE IMPREGNATED GOLD IS TRANSFORMED INTO WATER-INSOLUBLE NOBLE METAL COMPOUNDS, TREATING THE WATER-INSOLUBLE NOBLE COMPOUNDS WITH A REDUCING AGENT TO COVEY THESE COMPOUNDS SUBSTANTIALLY INTO THE CORRESPONDING NOBLE METALS AND REMOVING THE WATER-SOLUBLE COMPOUNDS WHICH ARE CONTAINED IN THE CATALYST BY WASHING, AND APPLYING AN ALKALI METAL COMPOUND BEFORE OR AFTER THE TREATMENT WITH THE REDUCIING AGENTS, THE ALKALI METAL COMPOUNDS CONSISTING OF ALKALI METAL CARBOXYLATES OR OF ALKALI METAL COMPOUNDS WHICH ARE WHOLLY OR IN PART TRANSFORMED INTO ALKALI METAL CARBOXYLATES UNDER THE REACTION CONDITIONS.

Inventors

• 👤 Walter Kroenig
• 👤 Gerhard Scharfe

Bibliographic Details