Environmentally safer processes

A United States Environmental Protection Agency report (Lin et al., 1994) contains an extensive review of inherently safer process chemistry options which have been discussed in the literature. This report includes chemistry options which have been investigated in the laboratory, as well as some which have advanced to pilot plant and even to production scale. 

Wixom, E. D. (1995). Building Inherent Safety into Corporate Safety, Health and Environmental Programs. CCPS Inherently Safer Process Workshop, May 17,1995, Chicago, IL. 

By modifying the catalyst with a so-called promoter (in this case vanadium oxide) it is possible to largely eliminate the intermediate. As Fig. 2.6 shows, the rate constant of the reaction from the hydroxylamine to the amine is much larger when the promoted catalyst is used, and thus the intermediate reacts instantaneously, resulting in a safer and environmentally friendlier process. 

Intensification of hazardous material results in a safer process. The minimization of waste will most often bring environmental benefits. 

The U S. EPA is funding research at Ionedge Corporation, Fort Collins, Colorado, to develop a process for zinc-graphite and zinc-cadmium alloy dry plating as environmentally safer alternatives to cadmium electroplating in cyanide baths. Successful development of these technique could lead to a method which would potentially eliminate the environmental and occupational hazards associated with cadmium electroplating. 

More and more the development of safer, more environmentally friendly processes becomes one of the main conditions for the survival of companies involved in Fine Chemicals production. Molecular sieve catalysts with their remarkable properties of shape selectivity and of easy tuning of their pores and active sites, etc. should play in the near future an essential role in the development of these processes. 

A dairy farm processing 100 ton of milk per day produces approximately the same quantity of organic products in its effluent as would a town with 55,000 residents. However, legislative regulations for the dumping of whey are forcing industries to come up with alternatives to make this process of elimination environmentally safer. One with attractive potential involves the use of thermophilic microorganisms to produce a... 

Heterogeneous catalysis has played a key role in the synthesis of CFC alternatives. However, for the process to be environmentally safer, the HCl must be recycled or sold. Although it is outside the scope of this chapter, it is important to recognize that new catalytic processes based on Deacon chemistry (eq 38) have been commercialized by Mitsui-Toatsa [114] using Cr-based catalysts. 

Major environmental trends that we see for land, air, water, and transportation of environmentally hazardous materials are shown in Box 9. These trends require that we get ahead of these issues and lead the chemical industry in the reduction of toxic metal (e.g., Sb, Sn, As) compounds, greenhouse gases, mercury emissions, and sulfur from gasoline and diesel, and find ways to control and sequester C02. Reduction of arsenic, as well as nitrates and ammonia, in drinking water is necessary. It is also imperative in these days of terrorism that we reduce transportation and storage of hazardous materials and continue our drive to develop inherently safer processes. 

Major challenges seem today even closer, including the synthesis of homochiral zeolites in the pure and separate form and their evaluation in asymmetric chemical and physicochemical processes, as well as crystalline zeolites with more open spaces, where larger molecules could be processed. Cheaper, faster, environmentally safer synthesis procedures should be sought, in particular with regard to the synthesis of hydrophobic pure-silica materials, where the use of HF should be avoided if a major industrial application is desired. In the coming years we may expect many beautiful new structures and exciting new chemistry within the zeolite field. 

In above situations, it is advisable to invest in research for new process and allocating fund for development of technology—which should result in a safer process for manufacturing of the products with better quality, having a better environmental pollution control and more overall efficiency (lesser raw material and energy consumptions, more equipment life, better use of manpower, etc.). 

In addition to providing safer and environmentally friendly processes, these newer surface treatments have also been shown to provide for easier and faster processing. They promise a potentially tremendous positive impact on both manufacturing cost and performance properties. The reduced cost impact can be in the form of equipment costs, implementation costs, operational costs, rework costs and storage/waste removal costs. 

However, to compare alternative routes solely on the basis of waste generation is an oversimplification. An environmentally friendly or favorable process, such as HF-based synthesis of ibuprofen, is not always a safer process. 

Palaniappan, C., Srinivasan, R. and Halim, I., 2002c, A Material-Centric Methodology for Developing Inherently Safer and Environmentally Benign Processes, Computers Chemical Engineering, Vol. 26(4/5), pp.757-774. 

Current trends in industrial production are toward the introduction of environmentally safer biotechnological processes, using microorganisms such as bacteria... 

The ambient condition, use of natural source in place of oxidative reagents, not only makes this methodology an alternative platform to the conventional route for the same, but it also becomes significant under the umbrella of environmental greener and safer processes. 

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