Coal Gasification

Coal gasification is the oldest method of extracting hydrogen. Coal is heated to 900°C; this way, it is transformed in coke oven gas. It is a gas that contains hydrogen, methane, oxide monoxide and a small amount of unsaturated hydrocarbon. The percentage of hydrogen is almost 60%. The gas is mixed with steam and nickel-based catalysts

Catalytic reforming

Catalytic reforming uses catalytic reactions to process primarily low-octane high-boiling straight-run gasoline into high-octane aromatics. Catalysts (Pt, Rh, etc.) are used in cyclisation and dehydrogenation, where hydrogen is a waste product.

Plasma reforming

There are several procedures using plasma reforming technology. The most known is the Kvaerner process, developed by a Norwegian company of the same name. Owing to new technologies, this is an environment-friendly process. Hydrocarbons are split into carbon and hydrogen in a reactor using a plasma burner at high temperatures (1600 - 2000°C). Compared to the other methods, the greatest advantage of this procedure is transforming carbon into soot without producing harmful CO2. Plasma reforming products are 48% of pure hydrogen, 40% of carbon in the form of soot and 10% of overheated steam. The disadvantage to other methods is high energy demands, 2-2.5 kWh energy per 1 m3 of H2.

This chapter described the most common methods of hydrogen production from fossil fuels. With time the efficiency of this methods increases, and energy demands decrease. The underlying problem of using fossil fuels to produce hydrogen is intensive by-production of greenhouse gases. They need to be stored permanently to prevent their release into the atmosphere. For this purpose, empty oil tanks or underground water reservoirs are used. A 1996 study showed that the capacity for storing greenhouse gases in Europe is 806 billion tons of CO2. Most of this capacity (476 billion tons of CO2) is on the Norwegian continental shelf in underground water reservoirs. This capacity would cover the CO2 produced by all power plants in western Europe for centuries.[1]