A method is provided of regenerating solvents used to remove gaseous contaminants from gaseous mixtures of various compositions with significantly reduced energy required, where one exemplary method includes directing a solution with the solvents and the preferentially absorbed and/or dissolved gaseous contaminants through a filter comprising a membrane having pre-determined diffusion rates so that a substantial portion of the gaseous contaminants pass through the filter, permitting the passage of the gaseous contaminants through the membrane for further processing, and recirculating the separated solvent so that it may be used again to remove new gaseous contaminants. In some cases, it may be desired to permit some of the solvent to pass through the membrane along with the gaseous contaminant.