Method of making a product gas mixture comprising providing a first gas mixture, contacting the first gas mixture with a lean absorber liquid at a first pressure and absorbing a portion of the first gas mixture in the lean absorber liquid to provide a rich absorber liquid and a non-absorbed residual gas, pressurizing the rich absorber liquid provide a pressurized rich absorber liquid, stripping the pressurized rich absorber liquid with a stripping gas at a second pressure greater than the first pressure to provide a pressurized lean absorber liquid and the product gas mixture, and reducing the pressure of the pressurized lean absorber liquid to provide the lean absorber liquid at the first pressure.