Abstract: A method for separating a cyclic urea degradation product from a solution, such as a scrubbing solution comprising n-cyclohexyl-1,3-propane diamine, an alkali metal carbonate and cyclic urea, is disclosed. The solution is passed to a vacuum crystallization zone wherein at least a portion of the cyclic urea is crystallized after which the solution is passed to a filtration zone for separation of the cyclic urea crystals from the solution.

Abstract: A process for the liquefaction of natural gas which employs a multi-component refrigerant system and a second independent refrigeration system. The process differs from the prior art processes in that the feed gas is cooled only by the independent refrigeration system until it has been freed of those components which could precipitate as solids at the low temperatures of the liquefaction process and thereafter is cooled by the multi-component refrigeration system. The multi-component refrigerant system is a self-contained cycle and does not reject heat to the independent refrigeration system, but directly to the ambient temperature surroundings.