MOULDABLE MATERIALS WHICH CAN BE USED AS A CATALYST

摘要

The present invention relates to mouldable materials which can be used as a catalyst for producing cyclic lactames by reacting aminocarboxylic acid nitriles with water in a liquid phase in a fixed bed reactor. The mouldable materials contain no reaction-soluble constituent and contain pyrogenic titanium dioxide as their main component. The mouldable materials can be obtained by moulding the pyrogenic titanium dioxide into moulded articles, and by processing the pyrogenic titanium dioxide before or after moulding with an acid in which it dissolves with difficulty, wherein said acid is taken in amount of between 0.1 and 30 wt % relative to said pyrogenic titanium dioxide.