MBTE, sometimes referred to as MTBE, is an additive to gasoline that is produced via the reaction of methanol and isobutylene. When this additive is put into gasoline, the fuel is then referred to as reformulated gasoline. While there are other uses for MBTE, the vast majority of large quantities produced are used as a fuel additive. The properties of methyl tertiary-butyl ether allow more oxygen into gasoline and as such it falls into a category of chemicals referred to as “oxygenates.” Other properties of MBTE include its colorless liquid phase, solubility in water, volatility and flammability at room temperature.
While there are numerous reasons for its use in gasoline, perhaps the most prominent reason is that it replaces lead as an octane enhancer. By replacing the lead in gasoline with the oxygenate MBTE, the fuel essentially become much cleaner. Since the institution of Clean Air Act Amendments in 1990 higher amounts of MBTE have been used in gasoline in various parts of the world to fulfill the requirements set by the act. In essence the fuel burning process is much more complete with the addition of methyl tertiary-butyl ether and as such tailpipe emissions that may be harmful to the environment are greatly reduced.
There are certain areas of the world where air pollution is at a much higher level than in other places. This is basically the reason behind the Clean Air Act Amendments introduced in 1990. The use of MBTE in gasoline to meet emission standards is to some extent arbitrary also as any other type of oxygenate, for instance ethanol, could very well be used to create the same desired effect. A simple and logical reason for the use of MBTE as opposed to ethanol is the fact that it is much less volatile and as such can be shipped through existing pipelines, thus meeting emission standards is much easier.
There is a wealth of benefits to using this reformulated fuel as opposed to regular gasoline. One such benefit is the reduction of smog forming pollutants and other damaging toxic compounds like benzene. Recent phases of the programs implementing the use of this reformulated gasoline have suggested that harmful emissions be reduced by a fairly sizeable amount as it is estimated that roughly 105 thousand tons of smog forming pollutants can be eliminated annually.
As with virtually everything, there is a flipside to using MBTE. Many people are concerned with the use of the additive in gasoline for numerous reasons. One such reason is that trace amounts of MBTE have been found in water supplies all over the continental United States. Even the presence of these trace amounts of methyl tertiary-butyl ether in drinking water can make the water absolutely impossible to drink as it leaves the water with a rather unpleasant taste and scent. Other disadvantages of the use of MBTE have been found by determining the effects of inhalation on humans. Though no humans were actually used in the experiments conducted, the effects witnessed in animals were astounding. These test subjects developed Cancer and various other health concerns, yet there are still organizations that feel that the use of MBTE is not harmful to humans and poses no threat to the public. The researchers cannot comment on the effects of swallowing anything containing the additive, as very little data actually exists on the matter. Data only for ingestion of water containing low concentrations and as such no real conclusions can be made regarding higher concentrations of MBTE. Researchers believe however that higher amounts of methyl tertiary-butyl ether contaminating the water can be potentially cancer causing if ingested.