5
Basic Concepts from Organic Chemistry
5.1 | INTRODUCTION
The fundamental information that environmental engineers and scientists need concerning organic chemistry differs considerably from that which the organic chemist requires. This difference is due to the fact that chemists are concerned principally with the synthesis of compounds, whereas environmental engineers and scientists are concerned, in the main, with how the organic compounds in liquid, solid, and gaseous wastes can be destroyed and how they react in the environment. Another major difference lies in the fact that the organic chemist is usually concerned with the product of the reaction: the by-products of a reaction are of little interest to him or her. Since few organic reactions give better than 85 percent yields, the amount of by-products and unreacted raw materials that represent processing wastes is of considerable magnitude. In addition, many raw materials contain impurities that do not enter the desired reaction and, of course, add to the organic load in waste streams. A classical example is formaldehyde, which normally contains about 5 percent of methanol unless special precautions are taken in its manufacture. Unfortunately, organic chemists have presented very little information on the nature of the by-products of reactions to aid environmental engineers and scientists in solving industrial and hazardous waste problems. Fortunately, this is changing because of the large liabilities that companies now face from discharge of environmental pollutants. Awards are now being given for “green chemistry,” that is, for changing the ways chemicals are produced in order to reduce the environmental harm they or their production cause. The environmental engineer and scientist, like the biochemist, must have a fundamental knowledge of organic chemistry. It is not important for either to know a multiplicity of ways of preparing a given organic compound and the yields to be expected
References: Brezonik, P. L.: Principles of Linear Free-Energy and Structure-Activity Relationships and Their Applications to the Fate of Chemicals in Aquatic Systems, in “Aquatic Chemical Kinetics,” W. Stumm, ed., Wiley-Interscience, New York, 1990. Carey, F. A.: “Organic Chemistry,” 4th ed., McGraw-Hill, New York, 2000. Loudon, G. C.: “Organic Chemistry,” 3rd ed., Benjamin/Cummings, Menlo Park, CA, 1995. Manahan, S. E.: “Environmental Chemistry,” 5th ed., Lewis, Chelsea, MI, 1991. Morrison, R. T., and R. N. Boyd: “Organic Chemistry,” 4th ed., Allyn and Bacon, Boston, 1983. 314 PART 1 Fundamentals of Chemistry for Environmental Engineering and Science Reinhard, M., and A. Drefahl, “Handbook for Estimating Physiochemical Properties of Organic Compounds,” John Wiley & Sons, Inc., New York, 1999. Schwarzenbach, R. P., P. M. Gschwend, and D. M. Imboden: “Environmental Organic Chemistry,” Wiley-Interscience, New York, 1993. Schwarzenbach, R. P. and P. M. Gschwend: Chemical Transformations of Organic Pollutants in the Aquatic Environment, in “Aquatic Chemical Kinetics,” W. Stumm, ed., Wiley-Interscience, New York, 1990.