Class Reflection

  To me, Green Chemistry is still about sustainability- the twelve principals are guidelines to this concept because they promote the use of renewable resources, reduce the use of resources that aren’t renewable, and focus on the prevention of environmental hazards, thus sustaining the earth.

The most interesting example of green chemistry is the use and production of alternative fuels.  By using these fuels we can reduce air pollution and no longer exclusively rely on foreign oil.  The process used to make these fuels, specifically biofuel, is relatively easy and can even be done at home.  Also, the amount of energy used to make these fuels equals the amount of energy produced so there is no negative effect on the environment.

When I began this class I had a hard time with some chemical principals- stoichiometry, air and gas laws, and balancing complicated chemical equations.  After this class, I feel more confident with all three of the areas I had trouble with in the beginning.

Water as a Green Solvent

As far as solvents go, water was the first; it has always been used to help man whether it was to help peel animal fat off of the hide or to wash blood off of hands.  Eventually, it was used to wash hair, bodies, clothes, and other items kept in homes.  Water is the best and most widely used solvent around now days; it is used as a base in products used to clean the house, used to clean beakers in chemistry labs, and still used to wash everything we as humans need. 

Now, water is being used in some places to decaffeinate coffee.  Originally, a harmful chemical like chloroform was used.  In the late 20^th century ethyl acetate was used because it was a chemical present in fruit and scientists said that it was a more natural choice, even though it was toxic.  The manufacturers eventually settled on the obvious choice, water.  The process is simple- the beans are placed in water, which soaks the caffeine and the flavor out of the beans.  Then, the beans are placed back in the water to restore the flavor but not the caffeine. 

Although water is the more natural choice, it is also the more expensive choice.  Scientists are now looking at ways to genetically engineer the beans to keep the caffeine from being produced in certain bunches of coffee beans.

Specific Air Pollutant

There are several specific pollutants that affect the quality of air that we breathe; one of these specific pollutants is sulfur dioxide.  Sulfur dioxide is let into the atmosphere by the combustion of fossil fuels at plants that create power, by other factories, and by using fuel that contains high amounts of sulfur.  The effects of this pollutant on human health are extreme- mild exposure can cause temporary breathing problems and more long-term exposure can long lasting respiratory effects, especially for asthmatics.  Sulfur dioxide particles can also bond with other particles and burry themselves in the lungs, causing or worsening respiratory diseases.

EPAs around the world are working together to create a list of ways to control emissions of this pollutant into the environment.  Factories and power plants are now placing monitoring devices at set points around the facility to see how much sulfur dioxide is being released into the environment.  There is also a comprehensive list of factories that emit SO₂ and the amount that they are emitting; the specific amounts will help environmental organizations formulate ideas on how to reduce the production and keep levels down.

 

Another idea is the use of alternative fuels, either biodiesel or ethanol.  The use of these fuels will not only reduce the emission of SO₂ in the environment but also promote the use of a renewable feedstock.  The use of alternative fuels will also help control other air pollutants that are being released into the environment.