Looking Back

     The end of the semester is getting near, and it's time to reflect on the class as a whole.  If I had to explain the field of green chemistry to a friend, I would say that it is a relatively new field that is still expanding and growing its ideas, and it also strictly follows the twelve basic principles of green chemistry, including: "Safer Solvents and Auxiliaries", "Design for Degradation", and "Inherently Safer Chemistry for Accident Prevention."
     The "Safer Solvents and Auxiliaries" means to use as less chemicals that could potentially harm the environment and  human health as possible.  For example, many soaps are made up of chemicals that could be easily replaced with natural ingredients.  Therefore, natural soap is the perfect example for this principle.  Next time buying soap, look for the ingredients and see if they are natural!
     "Design for Degradation" means designing materials to be biodegradable whenever possible.  Many companies have been trying to go by this principle, including Lay's.  They have now created biodegradable bags!
     Last but not least, "Inherently Safer Chemistry for Accident Prevention" means that we should plan to minimize (or completely eliminate) any potential chemical accidents.  This is certainly true for nuclear power plants:  when designing them, we have to make sure that contains lots of backup to prevent any accidents.

Corn as a Chemical Feedstock

     Many experts today agree that we cannot solely rely on fossil fuels as a source of energy for cars.  Therefore, we should look for alternative fuels by experimenting with chemical and engineering sciences.   For instance, through the fermentation of yeast, corn produces ethanol.  Today, ethanol is an additive to gasoline.  Now when I look at the gas pump and see the "contains 10% ethanol" sign, I'll think of corn.

     Corn doesn't solely produce ethanol, however.  Corn can also produce acetone and butanol: these are "high-value industrial solvents."  Butanediol can also be produced from corn: it's "an industrial solvent and a precurser to synthetic rubber."  Others chemical feedstock derived from corn include lactic, acetic, and citirc acid.

     There is a big problem with producing a chemical from natural microorganisms: they are extremely slow to produce and the concentrations are really low.  For instance, the fermentation of yeast to produce ethanol takes about twenty-four to forty-eight hours and about ten percent of the entire final product is ethanol (and these numbers are even worse when producing acetone and butanol from corn).  This, in turn, makes production very expensive and time consuming.    This is where biochemical engineers come in, researchers at the University of Illinois have found a way to mutate corn and other chemical feedstock to be more efficient.

Source:

 https://netfiles.uiuc.edu/mcheryan/www/feedstoc.htm

Durham's Cogeneration Plant

     When I first started to read about the cogeneration plant at the University of New Hampshire in Durham, I thought it was the coolest thing!  The cogeneration plant is a heat and power facility that is taking methane gas from nearby landfills and turning it into electricity.  UNH will receive eighty percent of their power and heat from pure methane, and they are the first university to use gas as a source of power.

     First, the methane gas from the landfill is collected and transformed into its pure form (from the help of  TREE).  Then, the gas is transferred to the University's cogeneration plant by traveling 12.7 miles through pipes underground.  The plant then transforms the gas into energy.  By doing this, UNH will be saving money and reducing greenhouse gas emissions (by 21 percent an academic year).

     To me (as I am sure it is for other people) this is huge!  I would rather have cities powered by natural gas rather than nuclear energy.  In an event of a nuclear melt down, we have to be able to control and secure the condition before it turns into a threatening situation.  I don't care how secure people think nuclear power plants are--the minute it's not secure it becomes dangerous.  If the cogeneration plant were to malfunction some day, we would have nothing to worry about!  Natural gas has no threat to the environment or humans.  I think methane gas (if this cogeneration plant really proves to be efficient) should be the future heat and power source of homes (at least partially, like what UNH is doing)!

Sources:

http://unh.edu/news/cj_nr/2009/may/bp19ecoline.cfm

http://www.unh.edu/users/unh/admin/sustain/climate_ed/cogen_landfillgas.html

Carbon Monoxide: Air Pollutant

     When I first think of carbon monoxide, I think of the cars that we drive that give them off.  Carbon monoxide does not just come from the cars that we drive, however.  They can come from volcanic activities, any man-made fire, and the burning of fossil fuels.  The amount of carbon monoxide present in the air varies from place to place, but urban areas tend to have higher levels, and the exhaust from combustion engines are the primary reason for this.

     What can carbon monoxide do to you?  Carbon monoxide goes directly into people's bloodstream.  There are higher levels of CO in the bloodstream of people that live in urban areas.  The problem is that the presence of CO in the blood slows down oxygen activity.  Therefore, the higher the levels of CO present, the harder it is to breathe in general--especially if one is exercising.  People living in urban areas probably experience more chest pain, shortness of breath, and even heart problems due to the higher levels of carbon monoxide in the air.  And of course, extremely high levels of CO can kill anyone.

      One way the EPA and the US Department of Energy are working to reduce the levels of carbon monoxide is by creating alternative vehicles that will take in other fuels.  We already have hybrid (both electric and gas fueled) and plain electric cars.  There are these new vehicles that that in natural gas (such as methane) instead of gasoline or diesel as fuel.  These new vehicles reduce the emission of CO by 90 to 97 percent!  This is great because these are and will continue to be the cleanest vehicles on earth.  Hopefully we'll be seeing more and more of these vehicles overtime.

Sources:

http://www.epa.gov/airquality/carbonmonoxide/health.html

http://www.afdc.energy.gov/afdc/vehicles/natural_gas_emissions.html

http://en.wikipedia.org/wiki/Carbon_monoxide

Green Agriculture

     Before the civil war, Virginia's driving economy was tobacco.  Everyone knows now that tobacco sucks the nutrients right out of the soil.  As a result, this makes the soil unsuitable for growing crops.  When Virginians first started growing tobacco, they began to see that growing tobacco in one spot for a long period of time had an effect on their quality overtime.  Eventually, they figured out a very practical, efficient, and green way to grow tobacco.

     Since there was no such thing as fertilizers back then, someone came up with the brilliant idea of rotating the tobacco by using different sections of the land every few years.  The first four years of growing tobacco was done in one section of the land.  When those years were up, they'd plant tobacco in another section and so on.  By the time the farmers came back to the first section of the land, the soil had enough time to recover from it's lack of nutrients.  This eventually led to the idea of crop rotation.

     Crop rotation was used by farmers and gardeners for a very long time to reduce infertile soil, diseases, and buildup of pests.  It is a three year rotation of crops.  For instance, you grow a certain type of crops for the first year, then a different type for the second year, and for the last year you let the soil recover for the next year.  Then the cycle begins again.  Another more modern type of crop rotation is having roots (potatoes), legumes (beans), alliums, and brassicas.  You can rotate these plants around every couple of years or so (by using different section of land) because every type of plant has a different role to play with the soil.  For instance, legumes--such as beans-- have a type of bacteria in their roots that can produce nitrogen (acting as a natural fertilizer) and roots--such as carrots- serve as a type of anti-bacterial in the soil (helps kill any potential disease or pest).  Rotating these crops around can produce a nice and healthy soil.

     This type of agriculture has definitely grown overtime, and it is very green!  It doesn't get any greener than this.  If you haven't clicked on the link above ("modern type of crop rotation") you should now.  It'll help you understand the modern crop rotation better.  It's highlighted in white.

Sources:

My knowledge of what I learned in history and botany class.

http://www.thegardenerscalendar.com/Guides/story.asp?nid=2677

Fertilizers and the Environment

     The topic of this blog is biological interaction with environmental chemicals.  Took me a little while to figure out what I was going to write about, but I finally stumbled upon fertilizers and the impact they can have on the environment around us.  There are two kinds of fertilizers: organic and inorganic.  I have decided to discuss about inorganic fertilizers and how it affects the environment.

     Many inorganic fertilizers are usually synthesized in the lab.  For instance using the "Haber-Bosch Process" produces ammonia as the end product.  The ammonia is added to fertilizers as feedstock and this becomes the inorganic fertilizer. I don't know about you, but ammonia in soil raises big red flags in my mind. The use of inorganic fertilizers have been increasing steadily in the last fifty years or so.  These synthesized fertilizers are mostly used to treat corn, barley, and even soy.  They can have beneficial effects when used in moderate amounts.

     Using excessive amounts of inorganic fertilizers can have some devastating effects, however.  "Over-fertilization" can throw off nutrient levels in the soil and it eats away the minerals that crops need. Using too much inorganic fertilizer can also cause something called "fertilizer-burn", where roots dry out and if not treated right away can cause the plant to die.

     The disadvantages of inorganic fertilizers are much worse than the disadvantages of organic fertilizers.  The biggest disadvantage that the organic fertilizers is that using too much of it could cause the plant to catch some form of disease.  Comparing it to inorganic fertilizers this is not that bad.  The problem is that it is much more expensive that inorganic fertilizers.  Because it is cheaper,  buyers tend to go for the inorganic fertilizers.  This is really unfortunate since organic fertilizers have a lot more benefits than the non-organic fertilizers.  The disadvantages are even better (if that makes any sense).

Source:

 http://en.wikipedia.org/wiki/Fertilizer

Water as a Green Solvent

     For this week, our class has to provide an example of when water is used as a green solvent.  Before I give my example, I would like to explain why water is a very good (if not the best) green solvent. Water is extremely safe to work with, it is beneficial to the environment, it is simple, and even cheap!  When you think that water couldn't get any better, it's physical properties top it off; water's temperature is very easy to control since it has very specific heat, water has very high surface tension (this is why water feels wet), and it allows molecules to move freely.

      An example where water is used as a green solvent is in sewer systems.  It starts when we flush the toilet.  The waste then goes to a large sewage system where it will undergo the first step of the treatment.  The first step involves the water sitting still, which allows the solids to sink (since they are heavier than water) and the scum to rise.  The solids are then removed and later end up in landfills.  The first stage removes about fifty percent of the solids and bacteria in the water.  The second stage removes about ninety percent of solids of and organic materials with the help of bacteria.  The water is constantly in motion, and this allows the bacteria to move around and eat anything in it's path.  The last stage includes the use of Chlorine to completely clean the water by killing any remaining bacteria and other wastes.

     The sewer example shows that water is very easy to work with to remove waste.  This process applies to many principles of green chemistry.  By using water we are avoiding chemicals that can potentially harm the environment, this process recycles water, it is very easy to monitor, and we do not have to worry about any chemical accidents!  Water is the greenest solvent anybody could ever use.  Because of this, water should be used whenever possible!

Sources:

http://www.slideshare.net/balmukund/water-a-green-solvent-with-a-diference

http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/S/SewageTreatment.html

http://en.wikipedia.org/wiki/Sewage_treatment

The Organic Compound, Urea

     Interestingly enough, urea was first discovered in 1773 in human urine.  Then sometime in the 1800's, scientists discovered a laboratory procedure to create urea: by dehydrating ammonium carbonate.  Today, urea has different functions for different things.  Though urea has many uses, it makes me feel less grossed-out that scientists don't use the urea that come from pee any longer, but rather the one that is synthesized in the lab.  Next, I will tell of some of the uses urea has.

     Of all of the compounds containing nitrogen in fertilizers, urea contains the most nitrogen.  Therefore, urea is used in nitrogen-based fertilizers in agriculture to help fertilize soil.  It can also be found in plastic to help prevent the material from shrinking, absorbing water, and breaking easily.  It is also found in SNCR (Selective Non Catalytic Reduction), a method to reduce nitrogen oxide emissions in power plants that burn up coal, fossil fuel, and biomass.  It can also be used medically for re-hydration of skin, such as lotions (again, this is why am I am especially glad the urea used here doesn't come from urine).

     Last but not least, urea can be used to help make the process of organic tie-dye better (t-shirt tie-dyeing).  Urea helps serve two purposes in tie-dye: first, it helps any undissolved dye to be completely dissolved (especially true for the darker colors).  Secondly, it serves as a "water-attractor", so it keeps the shirt wet just long enough for the reaction of the tie-dye to occur effectively.

     Urea is a reasonably safe organic compound compared to many chemicals.  Pure urea is actually odorless, so if you ever run across smelly urea, it has gone bad.  The beauty of bad urea is this: though it is useless for tie-dye or medical uses, it can still be used as a fertilizer.  Urea is a green and an organic compound.  It doesn't get any better than that.

Sources:

http://en.wikipedia.org/wiki/Urea

http://www.pburch.net/dyeing/FAQ/urea.shtml

Greener Batteries

     For this assignment, I have to look for a material that has been made safer by using a greener process.  At first, I really did not know what to look for.  After a while, I eventually decided to write this blog about batteries.  Though making greener batteries is still a growing idea, I am going to talk about the current ideas on making them greener.
      As we all know, hundreds of thousands of regular batteries are ending up in landfills on a regular basis, and this is a huge problem since the metals these batteries contain are very toxic to the environment.  If you didn't know this before, now you do!  To help solve this environmental threat, rechargeable batteries were created.  The problem now is that these rechargeable batteries are just sitting on the shelves.  More people are still using the old batteries (maybe because they are way cheaper, and you don't have to wait hours for them to recharge).  So scientists are putting their brains together and are discovering new ways to make batteries greener and even cheaper than today's rechargeable and old metal batteries.
     Scientists are thinking of creating metal-free batteries from (of all things) algae, they call it conductive polymer batteries.  These will be very lightweight made of paper coated in thin layers of composite electrode polymer materials (or algae).  The algae paper is great because it has got a wide surface area, so it can hold more of the conducting polymer than the products of the old toxic battery can.  These future batteries are going to be cheaper to make, recyclable, sturdy, and definitely greener!  It has still got a long way to go before we start to see them in the market.
     Another way that scientists are thinking of making batteries (specifically lithium ion rechargeable batteries) greener is by having them recharge at an even faster rate.  The crazy part of this is that they have discovered a way to make them recharge in a matter of seconds!  All they did was wrap the metal in glass (lithium phosphate), and discovered that this made the battery charge instantaneously.  Turns out, this coating also helps the battery keep it's charge longer.  Can you imagine your phone fully charged in just nine seconds or so?  That's really awesome.
     Hopefully in the future we'll be able to see these batteries take over the market for the sake of the environment.  I could not find any specific chemical reactions to prove that the new and improved batteries are better.  I did my best to explain how these batteries are greener. These are great new discoveries!

 Sources:

http://www.treehugger.com/corporate-responsibility/researchers-say-9-second-charging-battery-within-2-years.html

http://www.nature.com/news/2009/090311/full/news.2009.156.html
http://www.eco20-20.com/Greener-Batteries.html

Three Chemical Compounds

     I go to the kitchen and pick up the first can I see-- pizza sauce.  I read under "ingredients" and run across Citric acid.  The correct formula for Citric acid is C₆H₈O₇.  Turns out that it is mixed into foods and soft drinks to add a sour taste.  This would explain why I found it on the label of a pizza sauce.  It is also naturally found in many fruits and vegetables, but citrus fruits has concentrated amounts of it (such as limes, lemons, and oranges).  Citirc acid is a weak organic acid, which would explain why our mouths don't corrode after we eat an orange.  Thank goodness!
     Then from a can of black olives, I pick out the second compound: Ferrous gluconate (C₁₂H₂₄FeO₁₄), an iron based compound.  The reason why they put this chemical compound in the can is so then the olives could maintain their  black color.  Ferrous gluconate is also used for treating hypochronic anemia (people who have little iron in their system).  Taking too much of this chemical compound, however, can be toxic.  An overdose can cause someone to be in a coma, but this would only be an extreme case.  Milder symptoms include dehydration, nausea, and loss of skin color.
     Last but not least, a can of veggies contains Calcium chloride (CaCl₂).  This chemical compound has multiple purposes.  It is used to absorb moisture in air-tight containers, to prevent ice from forming (useful on road surfaces and car tires during extremely cold temperatures), to provide more taste for pickles (it has a salty taste), to treat hypocalcaemia (people with low blood calcium), and even to level out calcium levels in pool water.  The reason why the canned veggies contained CaCl₂ is because this chemical compound serves as a "firming agent" (it helps strengthen the structure of the vegetables while in the can).  So now I know why the vegetables maintain their firm shapes when we open a veggie can.  It's a great thing that CaCl₂ can do that for canned veggies, otherwise they would be old and mushy!

What is Green Chemistry?

     When I first heard that the chemistry class I registered for was called "green goggles chemistry" I thought it had a lot to do about using chemicals that were environmentally safe, recycling recyclable materials, and making a planet a greener environment somehow.  I began to realize, before reading my chemistry textbook, that the idea of making the Earth a greener place is still a relatively new and growing idea, at least it seemed that way to me.  After I read chapter one in my textbook, I figured out that I already had a pretty good sense of what green chemistry was all about, but it is much more than just recycling and using environmentally safe chemicals.
     Green Chemistry is the study of the interaction between inorganic chemistry, organic chemistry, physical chemistry, analytical chemistry, and biochemistry.  It is also the study of the interaction between the atmosphere, hydrosphere, geosphere, biosphere, and most importantly the anthrosphere.  These studies can then help scientists determine what is best for the environment.  They can make valuable decisions such as eliminating harmful substances to humans and its surrounding environment, preventing any unnecessary wastes, and recycling reusable materials.  These decisions that scientist can make are part of the twelve basic principles of green chemistry.  These principles (though I only named a few) are essential to making the environment a greener place to live in.
     As I said before, green chemistry is still a growing subject.  Because of this, it is important to have scientists willing to take risks and to try out new experiments that could potentially expand our knowledge of green chemistry.  I look forward to learning even more about green chemistry in the classes to come.