What is biodiesel? Biodiesel is a renewable, clean-burning diesel replacement that is reducing U.S. dependence on foreign petroleum, creating jobs and improving the environment. Made from a diverse mix of feedstocks including recycled cooking oil, soybean oil, and animal fats, it is the first and only EPA-designated Advanced Biofuel in commercial-scale production across the country … Read More

Developed in the 1890s by inventor Rudolph Diesel, the diesel engine has become the engine of choice for power, reliability, and high fuel economy, worldwide. Early experimenters on vegetable oil fuels included the French government and Dr. Diesel himself, who envisioned that pure vegetable oils could power early diesel engines for agriculture in remote areas … Read More

The physicochemical properties of biodiesel are nearly similar to diesel fuel. The most important properties for biodiesel are cetane number, heat of combustion, viscosity, oxidative stability, cold flow properties and lubricity (Knothe et al., 2005). Table 1 presents the main properties of microalgae biodiesel compared with diesel and 1st generation biodiesel. 1. The cetane number … Read More

Microalgae biodiesel and by-products must be separated for increasing the biodiesel production. The main separation processes used hot water (50?C) (Li et al., 2007), organic solvents such as hexane (Halim et al., 2010; Wiltshire et al., 2000) and water-organic solvent for a liquid-liquid separation (Couto et al., 2010; Lewis et al., 2000; Samorì et al., … Read More

The direct use of crude vegetable oils in diesel engines is envisageable, but could lead to numerous technical problems. For example, their characteristics (high viscosity, high density, difficulty to vaporize in cold conditions) cause deposits in the combustion chamber, with a risk of fouling and an increase in most emissions (Basha et al., 2009). These … Read More

In order to produce biodiesel from microalgae lipids, the later must be priory extracted. The main lipid extraction techniques are the use of chemical solvents, supercritical CO2, physicochemical, biochemical and direct transesterification. Chemical solvents extraction Chemical solvents method is by far the most commonly used, but less effective when microalgae are still wet (Samorì et … Read More

The large scale production of microalgae is generally performed with solar energy (photoautotrophic metabolism) in open ponds (raceways), closed systems (photobioreactors) or fermentors. Open ponds are generally circular with nested loops and are 30 cm deep (Chisti, 2007). However, ponds can have several non neglectable disadvantages. Indeed, as they are open, evaporation and contaminants (protozoa, … Read More

Finding new energy resources to compensate the decrease of the world petroleum reserves is an important challenge. The estimation of the world crude oil reserves is a difficult task because it is influenced by political, economic and technological factors (Pirog, 2005). The proven oil reserves represent the amount of petroleum that could be obtained from … Read More

There exists today a significant demand in industrialized countries for biofuels, driven largely by regulatory mandates for blending of biofuels into petroleum fuels. This demand is likely to grow considerably in the years ahead, driven by increasingly ambitious regulatory mandates, sustained high oil prices, and energy security concerns. Biofuel demands in many developing countries will … Read More

The effectiveness with which greenhouse gas emissions (GHGs, including CO2, CH4, and others) can be avoided using biofuels is related to the amount and carbon intensity of the fossil fuel inputs needed to produce the biofuel, as well as to what fossil fuel is substituted by use of the biofuel. A proper GHG accounting considers … Read More