ABSTRACT
The interest in steam reforming process as an efficient method for hydrogen production has been greatly increasing, due to its efficiency during hydrogen production and low environmental problems compared to other techniques. The main objective of this review was to present a comprehensive study of environmental, economic aspects of hydrogen production from steam reforming of raw materials such as biomass, bio-gas, ethanol, and natural gas. From literature review, it was found that among methods for hydrogen production, steam reforming of natural gas has lower installed capital due to the precence of high amounts of unconverted hydrocarbons in the produced gas (so-called tar) during other methods such as steam reforming of bio-gas.