New meanings of "green" that is being talked about.

We know it is good for health to eat organic food. We also know it will cost more to buy.

These days, "green" become popular and most widely used word. "Green food", "green energy", "green chemistry", "green economy", "green consumers", "green power","green chemicals", "green drink".....

Green may have many new meanings when people use it. It may mean clean, environmental friendly, healthy, technical advanced, more natural, and more.

But we need to know almost every "green" products are not cheap. Sometimes, it requires more sources or sacrifice more clean and healthy sources to produce one "green" product. Green is good but nowadays we need to know the cost to be "green".

Pump 'gas' from biomass: the journey from dream to reality (9)

Fermentation


Typically, fermentation is conducted at ~30 0C for 24-96 hours. The microorganisms include bacteria (such as Zymomonas molis and E. coli) and yeast (i.e. Saccharomyces cerevisiae).

Bactera:
–Embden-Meyerhof pathway and Entner-Doudorpff pathway
–High yield and ethanol tolerance

–Disadvantages
»Inability to convert complex carbohydrate to ethanol
»By-products such as sorbitol, glycerol and acetic acid

Yeast:
–Embden-Meyerhof pathway
–Very robust and well suited to SW lignocelluloses (mannose and later galactose)

But traditional baker's yeast only ferment C6 sugars and need engineer it by genetic modification to ferment both C5 and C6 sugars.

Algae: Can it be more effective for biodisel?

No doubt, algae has been a great feedstock to produce biofuel (biodisel) and attracted so much attention from researcher, industry, business people, investors, public policies, and goverment officials. Because of the 2008 Algae Summit, algae wind spread almost every corner of the world; algae is booming.

When talking algae about its potential being biofuel, , people may focus more on these facts: "algae can flourish in non-arable land or in dirty water, and when it does flourish, its potential oil yield per acre is unmatched by any other terrestrial feedstock". My question is: can we do the transgenetic modification by transfering the genes from high oil yield plants into algae to increase its oild yield? What are the technical barriers?

Any new possibilites for biomass treatments ?

To convert lignocellulosic biomass to simple sugars, conventional methods use acid or base at high temperatures and pressures or combined enzymatic saccharification, which require large amounts of energy inputs or take long time.

Since the main barrier is the interference of lignin and the crystal structure of cellulose,one approach may be to utilize cellulose swelling agents to destroy the cristal structure; the other one may be to use lignin dissolving agents to remove part of lignin. As a result, the rate of saccharification will be speeded up from either of the treatments.

Biobutanol

Butanol is a 4 carbon alcohol and used primarily as an industrial solvent and can replace for gasoline as a fuel without major engine modifications. It has a lot of advantages:

• high energy content: 110,000 btu/Gal. Ethanol: 84,00 btu/Gal;Gasoline: 115,00 btu/Gal.
• 6 times less evaporation than ethanol and 13.5 times less than gasoline
• cost less than ethanol
• can be made from biomassrenewable and could be produced in distributed biorefineries scattered across the landscape

Now the questions are:

1. Why is the butanol not declared as an alternative fuel sources by government like ethanol?

2. Why aren't there more extensive research and commercialization activities on bio-butanol production?

3. What are the major barriers for its production and commercialization?