BIO FUEL SYNTHESIS FROM ALGAE

Hypothesis

• Does increase in the production of bio-fuels have a negative effect on food production?

• Would using algae curb the global food demand ?

• How would this energy source be made more useful to our engines or engines made to siut this energy source?

Active Components AlgaeAlgal biomass contains three main

components: carbohydrates, protein and lipids/natural oil. Because the bulk of the natural oil made by microalgae is in the form of triacylglycerides(TAGs).

How is it made?Studies show that some species of algae can produce up to 60% of their dry weight in the form of oil. Because the cells grow in aqueous suspension, where they have more efficient access to water, CO2 and dissolved nutrients, microalgae are capable of producing large amounts of biomass and usable oil in either high rate algal ponds or photo bioreactors

How it’s madeMicroalgae grow very quickly compared to terrestrial

crops. They commonly double every 24 h. During the peak growth phase, some microalgae can double every 3.5 h. Oil contents of microalgae are usually between 20-50% (dry weight) (Table 2-1), while some strains can reach as high as 80%. The fatty acids attached to the TAG within the algal cells can be both short and long chain hydrocarbons. The shorter chain length acids are ideal for the creation of biodiesel, and some of the longer ones can have other beneficial uses. For example, several species of alga have been investigated for their production capabilities of omega-3 fatty acids

Storing Methods

An Algae Culture System

Chemical structures of nucleotides

Phosphate groups Nitroge

nous base

(adenine

shown)

Sugar (ribose in ribonucleotides; deoxyribose in deoxyribonucleotides)

in deoxy-ribose

Nucleoside (sugar + nitrogenous base)

Nucleoside monophosphate (adenosine or deoxyadenosine monophosphate)Nucleoside diphosphate

(adenosine or deoxyadenosine diphosphate)

Nucleoside triphosphate (adenosine or deoxyadenosine triphosphate)

In ribose

Glucose subunit

Cellulose molecule

Cellulose microfibrils in plant cell wall

Cellulose microfibril

Cellulose

Mechanisms

The above mechanism is a common organic chemistry reaction known as transesterification.

RCOOR' + R"OH cat RCOOR" + R'OH

Transesterification Mechanisms

Mechanisms cont’d

Summary Mech.

LimitationsThe major limitation for algal biodiesel is the production cost and energy input required while producing and harvesting the micro-algal biomass. Different researchers claim different theories on this topic. When considering net energy inputs and life cycle fossil fuel inputs, one researcher concluded that bio-fuels from microalgae were not even capable of out-producing terrestrial plants (Reijnders 2008). This concern sparked off a reply that furthermore proved that microalgae still beat bio-fuels from terrestrial plants even when including these new factors. Other studies concluded that the high moisture content of microalgae means drying it before using it for energy production would be too great an energy usage