ABSTRACT
Natural gas is a mixture of hydrocarbons ranging from methane to C7 or higher. The lighter hydrocarbons are paraffinic; those corresponding to naphtha cut also consist mostly of paraffins but include small amounts of naphthenes and occasionally aromatics. In countries where natural gas is plentiful, methane is also the raw material for producing synthesis gas. Natural gas constituents heavier than methane are also excellent petrochemical feedstocks. In addition to producing a liquid fuel such as ethanol, biomass can also be converted into methane. In areas where natural gas resources are scarce, biomass conversion into methane serves as an attractive process, since methane is a very conveniently usable gaseous fuel for domestic energy needs. In the absence of oxygen, but in the presence of water, the organic matters will ferment naturally, and 60–80% of the carbon is converted into carbon dioxide, methane, and small amounts of hydrogen sulfide and nitrogen.
