New Process Doubles Production of Alternative Fuel

A new discovery should make the alternative fuel butanol more attractive to the biofuel industry. University of Illinois scientist Hao Feng has found a way around the bottleneck that has frustrated producers in the past and could significantly reduce the cost of the energy involved in making it as well.

“The first challenge in butanol production is that at a certain concentration the fuel being created becomes toxic to the organism used to make it (Clostridium pasteurianum and other strains), and that toxicity limits the amount of fuel that can be made in one batch. The second issue is the high energy cost of removing butanol from the fermentation broth at the high concentrations used by the industry. We have solved both problems,” he said.

In the study, funded by the Energy Biosciences Institute, Feng’s team successfully tested the use of a non-ionic surfactant, or co-polymer, to create small structures that capture and hold the butanol molecules.

“This keeps the amount of butanol in the fermentation broth low so it doesn’t kill the organism and we can continue to produce it,” he said. This process, called extractive fermentation, increases the amount of butanol produced during fermentation by 100 percent or more.

But that’s only the beginning. Feng’s group then makes use of one of the polymer’s properties—its sensitivity to temperature. When the fermentation process is finished, the scientists heat the solution until a cloud appears and two layers form.

“We use a process called cloud point separation,” he said. “Two phases form, with the second facing the polymer-rich phase. When we remove the second phase, we can recover the butanol, achieving a three- to fourfold reduction in energy use there because we don’t have to remove as much water as in traditional fermentation.”

A bonus is that the co-polymers can be recycled and can be reused at least three times after butanol is extracted with little effect on phase separation behavior and butanol enrichment ability. After the first recovery, the volume of butanol recovered is slightly lower but is still at a high concentration, he said.

According to Feng, alternative fuel manufacturers may want to take another look at butanol because it has a number of attractive qualities. Butanol has a 30 percent higher energy content than ethanol, lower vapor pressure, and is less volatile, less flammable, and mixes well with gasoline, he noted.

Different Types Of Alcohol Chemicals

Alcohol products are all around you, from cleaning supplies to face cleaner to the fuel in your car or the wine you drink with dinner. In chemistry, there are three major types of alcohol. These include isopropyl alcohol, methyl alcohol and ethyl alcohol. Each of these types of alcohol has separate properties, so it is important to distinguish which type of alcohol you have for reasons of safety.

Methyl Alcohol
Methyl alcohol, also called methanol and wood alcohol, is used primarily as an industrial solvent. It is also used to make formaldehyde for plastics, paint and plywood. Methyl alcohol is used in windshield wiper fluid. For example, it is a component in paint remover and photocopier developer. People also use methyl alcohol to make other chemicals. This is because a by-product of degrading methanol is formaldehyde, which may be used to make everything from plastics to explosives. It also works to fuel internal combustion engines and keep fuel from freezing. The chemical formula for methyl alcohol is CH3OH.

Ethyl Alcohol
Ethyl alcohol, or ethanol, is the type in wine, beer, liquor, mouthwash or cold medicine. People usually take ethyl alcohol in a diluted concentration–the level of the concentration is known as the proof of the alcoholic beverage. Ethanol is also used in gasoline, It can be made from corn, sugar cane and potatoes, much like drinking alcohol is distilled from food crops such as wheat, potatoes and corn.

Isopropyl Alcohol
Isopropyl alcohol also is called isopropanol or 2-propanol. More commonly, it is known as rubbing alcohol due to the practice of physicians rubbing the substance on the body for cooling and disinfecting. Produced by combining water and propylene, rubbing alcohol works well for sterilization. Its high evaporation rate makes it a first choice for cleaning electronics, although it is found in everyday cleaning products, as well. Isopropyl alcohol also is found in cosmetics, including lotions. The chemical formula for this type of alcohol is C3H8O.

Butyl Alcohol
Adhesives and varnishes are traditionally made from butyl alcohol. Floor polishes and other cleaners sometimes contain it. Butyl alcohol(C4H10O), also known as 1-butanol or Butanol, also may be present in eye makeup, foundation and lipstick. It is also a component of gasoline and brake fluid, according to the Dow Chemical Co. website.

Ethylene Glycol
Ethylene glycol is primarily used in the manufacture of automotive antifreeze. It is extremely toxic if ingested.