NOVELTY - Processing a stream containing butene and/or butadiene, butane, hydrogen, nitrogen and carbon dioxide, comprises (a) absorbing the stream with a mixture containing N-methylpyrrolidone and water to obtain a stream (9) containing N-methylpyrrolidone, water, butene and/or butadiene, butane and optionally carbon dioxide and a stream (7) containing hydrogen and/or nitrogen and butane, (b) carrying out extractive distillation of the resulting stream with stream containing N-methylpyrrolidone and hydrogen, and (c) distilling the stream containing N-methylpyrrolidone, water, butene and/or butadiene.    USE - The method is useful for processing a stream containing butene, butadiene, butane, hydrogen, nitrogen and carbon dioxide.    ADVANTAGE - The method is carried out in a simple and cost efficient manner.    DETAILED DESCRIPTION - Processing a stream containing butene, butadiene, butane, hydrogen, nitrogen and carbon dioxide, comprises (a) absorbing the stream containing butene and/or butadiene, butane, hydrogen and/or nitrogen and optionally carbon dioxide with a mixture containing N-methylpyrrolidone (80-97 wt.%) and water (3-20 wt.%) to obtain a stream (9) containing N-methylpyrrolidone, water, butene and/or butadiene, butane and optionally carbon dioxide and a stream (7) containing hydrogen and/or nitrogen and butane, (b) carrying out extractive distillation of the stream containing N-methylpyrrolidone, water, butene and/or butadiene, butane and optionally carbon dioxide with stream containing N-methylpyrrolidone (80-97 wt.%) and hydrogen (3-20 wt.%), where the stream containing N-methylpyrrolidone, water, butene and/or butadiene, butane and optionally carbon dioxide is separated into a stream (17) containing N-methylpyrrolidone, water, butene and/or butadiene and a stream containing butane and optionally carbon dioxide, and (c) distilling the stream containing N-methylpyrrolidone, water, butene and/or butadiene into a stream (23) containing N-methylpyrrolidone and water and a stream (21) containing butene and/or butadiene.    DESCRIPTION OF DRAWING(S) - The figure shows a schematic process flow of the method.    Stream containing hydrogen and/or nitrogen and butane (7)    Stream containing N-methylpyrrolidone, water, butene and/or butadiene, butane and optionally carbon dioxide (9)    Stream containing N-methylpyrrolidone, water, butene and/or butadiene (17)    Stream containing butene and/or butadiene (21)    Stream containing N-methylpyrrolidone and water (23)