Fundamentals of cleaner technology in the chemicals industry.

Basic synthetic processes start with more or less inert material of natural origin, both inorganic and organic matter. Process energy is the agent for converting starting material of low reactivity into highly reactive derivatives or elements. The principles of chemical reactions as first steps of synthesis are explained along with the formation of by-products. The second steps of applying separation techniques for purposes of concentration and purification of products desired and of extracting unwanted and harmful products to be reused or eliminated are presented as critical examples. Reuse of by-products within the limits of chemical recycling, as well as degradation or final waste disposal, are shown as third steps. A concept of cleaner technology is outlined as an unachievable aim due to natural limitations of both entropy and energy.