Chemistry Associated with Pollution Processes

Gas-phase HO- is generated by photolysis of HOOH and by cosmic radiation and solar radiation of O2/H2O in the atmosphere. The latter process is an important contributor to the atmospheric chemistry associated with organic pollutants. The gas-phase reactions of HO- with organic molecules have been exhaustively reviewed and summarized in a recent compendium. In aqueous solutions, HO- is produced by radiolysis (continuous and pulsed) (equation 87), ... 

The purpose of this chapter is to deal with the surface modification of cellulose fibres in order to provide them with specific functionalities, so that they can play determining roles in such applications as reinforcing elements for composite materials, self-contained composite structures, anti-pollution aids, hybrid materials, superhydrophobic surfaces and conductive and magnetic materials. Other types of surface modifications, such as those associated with dying or the manufacture of chromosorb, enzymatic and ion-exchange supports, fall outside the scope of this review. Within the structure of this book, this chapter constitutes in many ways a bridge between the chemistry associated with bulk modification treated in Chapter 16 and the processing and properties of composite materials in Chapter 19, with the addition of more specific aspects. 

Black chemistry stands for waste = pollution and conjures up images of the industrial revolution, black smoking chimneys and Blake s dark satanic mills. Red chemistry, on the other hand, denotes danger and evokes associations with incidents such as Bhopal and Seveso. Many chemical processes in use today are black or red, or both. Hence, the goal of the chemical industry is, or should be, the replacement of red and/or black chemistry vfith green alternatives. ... 

A great deal of the environmental concern associated with chemical manufacture comes from not merely the chemicals that are made or the chemicals from which they are made, but from all of the substances associated with their manufacture. In the manufacture, processing, formulation and use of chemical products, there are a variety of associated substances that contribute to the environmental loading from chemical manufacture. The most visible of these associated substances are the solvents used in reaction media, separations and formulations. Many solvents, especially the widely used volatile organic solvents, have come under increased scrutiny and regulatory restriction based on concerns for their toxicity and their contributions to air and water pollution. It is for these economic and environmental reasons that much of the research and development in Green Chemistry reaction conditions is focussed on alternative solvents. 

A critical but poorly understood factor related to atmospheric exposure is the connection between nominal environmental conditions (e.g., humidity, ultraviolet radiation, pollution, atmospheric particles, and so on) and the actual chemistry of the environment on the material s surface. Time-of-wetness is known to be an important parameter in outdoor exposure, given that water associated with precipitation or condensation is critical to the corrosion processes. However, accurate prediction of corrosion rates depends on knowing how the water on the surface affects the concentration of all the important corrosive species. 

There are over 280 million scrap tires produced annually in the United States. Of these over 100 million are used as fuel and most of these are burnt to supplement fuel use in cement and other rotary kiln operations. The cement process is particularly convenient for tire combustion because the reinforced steel wire in the tire tread can be a source of iron for the cement chemistry. Kilns burning tires must comply with the EPA s boiler and industrial furnace act and hence are heavily regulated as a pollution source. Table 6.3 gives a typical average composition of tires supplied by the Rubber Manufacturers Association of America. 

Professor Maria Turco is Associated Professor at the Faculty of Engineering of University Federico II of Napoli, where she teaches courses in Industrial Chemistry, Traditional and Innovative Fuels and Fnel Cells, and Catalysis . Professor Maria Tnrco carried ont research activity, mainly in the field of the technologies for the production of energy with low environmental impact, such as catalytic processes for removal of gaseous pollutants and processes for hydrogen production. A large part of her recent activity is devoted to the study of fuel cells for mobile or stationary apphcations. 

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