Abstract: The present invention provides for a process for converting a feedstock comprising ethylene and/or acetylene to a product comprising liquid hydrocarbons. The process comprises maintaining said feedstock at a temperature in the range of about 700.degree. C. to about 1000.degree. C. for about 100 to about 1000 milliseconds to provide for said conversion. In one embodiment, the feedstock further comprises hydrogen. In another embodiment the feedstock comprises the product made by the process comprising heating a gaseous mixture comprising (i) hydrogen and (ii) natural gas and/or at least one light hydrocarbon at a temperature of at least about 1250.degree. C. for an effective period of time to provide said feedstock. In still another embodiment, the feedstock further comprises natural gas and/or at least one light hydrocarbon in addition to said ethylene and/or acetylene.