Process for oil recovery

A process for recovering oil and gas from an underground formation by injecting an ammonia containing enhanced oil recovery formulation into the oil-bearing formation, which process comprises

• (i) reacting steam with methane containing gas in the presence of a steam reforming catalyst at a temperature of from 700 to 1100° C. to obtain hydrogen and carbon monoxide,
• (ii) combining the reaction mixture obtained in step (i) with further steam to obtain a product containing carbon dioxide and more hydrogen,
• (iii) removing carbon dioxide from the product of step (ii) to obtain hydrogen,
• (iv) reacting at least part of the hydrogen obtained in step (iii) with nitrogen at a pressure of 15 to 35 MPa and a temperature of from 400 to 500° C.,
• (v) separating ammonia from the reaction mixture obtained in step (iv),
• (vi) mixing ammonia obtained in step (iv) with water and injecting enhanced oil recovery formulation containing this mixture into the underground formation via a production well,
• (vii) recovering oil and gas from the underground formation via a recovery well,
• (viii) separating methane containing gas from the fluid recovered from the recovery well,
• (ix) removing sulfur compounds from at least part of the gas which has been separated off to obtain treated methane containing gas, and
• (x) using in step (i) the treated methane containing gas obtained in step (ix).