Metals manufacturing, waste reduction

Source Reduction and Recycling Activity for Nonferrous Metals Manufacturing Wastes... 

Waste reduction methods of specific interest to PC board manufacture are discussed below 11.1.3 SOURCE REDUCTION 11.1.3.1 Metal Complexes... 

This process will allow the recycling of solid waste to produce a useful product. High pressure and temperature combined with hydrogen can convert most types of domestic and industrial wastes back into products that are currently obtained from fossil coal and oil. No volatile polluting chemicals will be vented into the atmosphere. The metals can be recovered for further use and the ceramic materials will be converted into a product difficult to distinguish from natural rocks. This type of process will not solve all the solid waste disposal problems, but will provide a potential method for recovery of valuable products from waste. When implemented, it will dramatically reduce the amount of solid waste placed in landfills. This process also has the potential to reduce the amount of oil and coal mined to provide the carbon compounds needed to manufacture all petrochemical derived materials. This waste reduction process is a variation on the Fischer-Tropsch process, mentioned on page 101, in use commercially to produce hydrocarbon materials from coal. 

Guidelines for Waste Reduction and Recycling Metal Finishing, Electroplating, Printed Circuit Board Manufacturing... 

EPA used the WMPT as a basis for a proposed voluntary waste reduction scheme. This has left the manufacturers of color pigments, which were categorized incorrectly in the beginning of this process, to continue arguing for some rational means of removing the unwarranted PBT label. The EPA proposed that industry reduce voluntarily by up to 50 % wastes containing a list of 53 constituents. These constituent chemicals included a list of metals. The listed metals included aU compounds of lead, cadmium, nickel, arsenic, antimony, copper and zind l... 

In comparison with the rhodium-catalyzed process, the biocatalytic process provides sitagliptin with a 10-13% increase in overall yield, a 53% increase in productivity, a 19% reduction in total waste, the elimination of all heavy metals, and a reduction in total manufacturing cost the enzymatic reaction is run in multipurpose vessels, avoiding the need for specialized high-pressure hydrogenation equipment [28]. 

Many applications, especially in electrochemistry, rely on the use of expensive and rare metals, like Pt, Li, and rare-earth elements. In the synthesis of micro- and me-soporous materials, costly structure-directing agents are sometimes applied. The reduction of catalyst mass and the prevention of waste formation, for instance by recycling of synthesis additives, are therefore highly topical research issues. The practicability of future technologies based on catalysis will depend on the availability of efficient catalysts composed of abundant elements prepared by robust, preferentially aqueous-based synthesis methods and the reduction of environmental impacts arising from catalyst manufacture. 

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