Clean process technology catalyst waste

Today s society asks for technology that has a minimum impact on the environment. Ideally, chemical processes should be clean in that harmful byproducts or waste are avoided. Moreover, the products, e.g. fuels, should not generate environmental problems when they are used. The hydrogen fuel cell (Chapter 8) and the hydrodesulfurization process (Chapter 9) are good examples of such technologies where catalysts play an essential role. However, harmful emissions cannot always be avoided, e.g. in power generation and automotive traffic, and here catalytic clean-up technology helps to abate environmental pollution. This is the subject of this chapter. 

Whereas such applications of catalytic clean-up technology are of obvious importance, it is even more desirable to develop new catalytic processes that produce less or no waste products. Many conventional routes consume acids or bases and produce salts which cause waste problems. The production of ethylene epoxide from ethylene by direct oxidation over silver catalysts forms an example for a clean, catalytic process which has replaced traditional routes involving the... 

Pyrolysis is the treatment of plastic waste in the presence of heat under controlled temperatures without catalysts. The pyrolysis process is an advanced conversion technology, in which the hydrocarbon content of the waste is converted into a clean, high calorific value gas from a wide variety of plastic waste. The produced gas can be utilized in gas engines, electricity generation, or in boiler applications. 

The Victor Company of Japan, in collaboration with the National Institute of Advanced Industrial Technology and Clean Japan Centre (CJC), is developing a process to recover high-purity bisphenol A from waste optical disks, typically CD, CD-ROM and DVD. The new process decomposes PC resin at around 200 °C in a nitrogen atmosphere under 2 MPa pressure, using sodium carbonate in cyclohexanol as a catalyst. In CJC simulations it was shown that was possible to secure an 80% yield of 99.9% pure bisphenol A. 

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