Process for separating a hydrogen-comprising hydrocarbon mixture (C2minus) comprising in addition to the hydrogen essentially hydrocarbons having two carbon atoms and methane using a distillation column where - fluid (a, c, e) of the hydrocarbon mixture (C2minus) at a first pressure level is cooled stepwise from a first temperature level via two or more intermediate temperature levels to a second temperature level, wherein at each of the intermediate temperature levels first condensates (b, d) are separated from the fluid (a, c, e), - fluid (e) of the hydrocarbon mixture (C2minus) which at the second temperature level remains gaseous is fed at the first pressure level into a C2 absorber to the top of which a liquid reflux (r) is applied, wherein from the bottom of the C2 absorber a second condensate (f), and at the top of the C2 absorber a predominantly methane- and hydrogen-comprising gasesous tops stream (g) are withdrawn, - fluid of the gaseous tops stream (g) from the top of the C2 absorber is cooled to a third temperature level and at the first pressure level is transferred into a hydrogen separator in which from the fluid of the gaseous tops stream (g), to leave behind a gaseous hydrogen-rich stream (h), a methane-rich third condensate (i) is separated and - fluid of the first condensates (b, d) and fluid of the second condensate (f) are decompressed from the first pressure level to a second pressure level below the first pressure level and fed into the distillation column which is operated at the second pressure level, wherein in the distillation column at least a liquid stream (o) which consists essentially of hydrocarbons having two carbon atoms and a liquid stream (m) which consists essentially of methane are derived and are withdrawn from the distillation column, characterized in that the reflux (r) applied at the top of the C2 absorber is formed from fluid of the third condensate (i) which is separated in the hydrogen separator from the fluid of the gaseous tops stream (g) from the top of the C2 absorber and transferred exclusively by the action of gravity from the hydrogen separator into the C2 absorber. - fluid (a, c, e) of the hydrocarbon mixture (C2minus) at a first pressure level is cooled stepwise from a first temperature level via two or more intermediate temperature levels to a second temperature level, wherein at each of the intermediate temperature levels first condensates (b, d) are separated from the fluid (a, c, e), - fluid (e) of the hydrocarbon mixture (C2minus) which at the second temperature level remains gaseous is fed at the first pressure level into a C2 absorber to the top of which a liquid reflux (r) is applied, wherein from the bottom of the C2 absorber a second condensate (f), and at the top of the C2 absorber a predominantly methane- and hydrogen-comprising gasesous tops stream (g) are withdrawn, - fluid of the gaseous tops stream (g) from the top of the C2 absorber is cooled to a third temperature level and at the first pressure level is transferred into a hydrogen separator in which from the fluid of the gaseous tops stream (g), to leave behind a gaseous hydrogen-rich stream (h), a methane-rich third condensate (i) is separated and - fluid of the first condensates (b, d) and fluid of the second condensate (f) are decompressed from the first pressure level to a second pressure level below the first pressure level and fed into the distillation column which is operated at the second pressure level, wherein in the distillation column at least a liquid stream (o) which consists essentially of hydrocarbons having two carbon atoms and a liquid stream (m) which consists essentially of methane are derived and are withdrawn from the distillation column,