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.   

Chemical Compounds Found in Generic Ibprofen

Whether we like it or not, chemistry is a part of our daily lives.  The products of chemistry (compounds and reactions) can be found in everything from toothpaste, to antibacterial hand soap, to gas, to even some processes in our body.  Without chemistry, or the chemical compounds that scientists have been working to create and perfect, the world would not have plastics, pharmaceuticals, or daily hygiene items.  While looking at a generic bottle of ibuprofen, I noticed about a dozen chemical compounds on the back; I decided to take a closer look at three of them.

Hypromellose (aka Hydroxypropyl methyl cellulose)- This compound is used in a wide variety of items including cosmetics, paint, and cement.  Currently, research is being conducted to see if hypromellose can be used to replace gluten in breads.

CH₂CH(OH)CH₃

Polyethylene Glycol- This is used mainly in medications because it causes medicines to last longer and reduces the toxicity of the drug.  It is also used as the basis of many skin creams.  Research being done on this compound includes using it in gene therapy.

C_2NH_4N + 2O_N+1

Titanium Dioxide- The main use of this compound is for light refraction.  It is used in lines on tennis courts, materials to build space shuttles, and in all sunscreen- and in all cases to redirect the light. 

TiO₂

All of the chemicals listed are not only found in ibuprofen, they are also found in many other items.  Most compounds are versatile- they have many uses in very different places.  It is this versatility that makes chemical compounds essential in manufacturing the things we frequently use today.

What is Green CHemistry?

Green Chemistry is something that is completely new to me.  I took a general chemistry course at St. Anselm last year and nothing about green chemistry, even the existence of it, was mentioned.  Now, as I read the textbook and other sources about green chemistry I don't know why it wasn't mentioned.  Green chemistry is not throwing the ideas of traditional chemistry out the window; it is enhancing chemistry, making it friendly to a more conscientious world.

Green chemistry isn't just a focus of the impact of chemicals and by-products on the environment.  It also evaluates the impact of chemistry on the economy.  Chemicals, experiments, and research can begin to cost a great deal of money, especially because experiments must be done more than once.  With green chemistry, reduce, reuse, and recycle (now a common phrase) will help lower the final cost of the project or help sites break even.  Green chemistry also helps reduce waste.  Any person who has taken a chemistry lab knows that something has to be produced by the end of the lab in order to complete the report correctly.  Now imagine that on a larger scale put into toxic waste dumps.  These dumps have the power to completely alter the soil in which they are put.  The last concept that green chemistry covers is the reuse and recycling of materials.  With the constant use of recycled materials there will be little or no need to dip into unused resources. 

The three concepts above come from the text book to illustrate sustainability (a word that pops up constantly).  This sustainability is what I think green chemistry is all about.  If the world or even individual sites can reduce, reuse, and recycle enough, chemistry can become a sustainable science.