Environmental impact, lead copper

Human toxicity, aquatic toxicity, and the environmental impact of engine coolants and deicing fluids ate typically measured on the fresh fluid only. Spent fluids contain varied contaminants that can drastically affect the toxicity and environmental impact of the fluid. Most pronounced is the impact of heavy-metal contaminants in spent antifreeze. Data on spent and recycled antifreeze, compiled by the ASTM Committee on Engine Coolants, show an average lead level 11 ppm, as weU as various other metal contaminants (iron, copper, zinc) (18). The presence of these contaminants in a used fluid may require special disposal techniques for the fluids. 

Secondary metal production is advantageous not only with respect to energy consumption but also to environmental impact as compared to primary metal production. The important environmental problems pertain to the formation of dioxins during thermal processing and the generation of dusts of the oxides of zinc, lead, and other metals in secondary steel, copper, and zinc production. 

Spurgeon, D.J., SR. Hopkin, and D.T. Jones. 1994. Effects of cadmium, copper, lead and zinc on growth, reproduction and survival of the earthworm Eiseniafetida (Savigny) assessing the environmental impact of point-source metal contamination in terrestrial ecosystems. Environ. Pollut. 84 123-130. 

While the environmental impact of cadmium azide in deep oil deposits is relatively low, the long-term use of Pb(N3)2 and lead styphnate in military training grounds has resulted in considerable lead contamination (see Ch. 1.2.3, see Fig. 1.17). On demand lead azide (ODLA) is available from the reaction of lead acetate and sodium azide. The recently introduced iron and copper complexes of the type [Cat]2 [Mn(NT)4(H20)2] ([Cat]+ = NH4, Na+ M = Fe, Cu NT = 5-nitrotetra-zolate) as green primary explosives [3] are relatively easily obtained and show similar initiator properties as those of lead azide (Tab. 2.2). 

Phosphates and silicate corrosion inhibitors have been used with or without pH control, to reduce the metal release and to prolong the service life of distribution systems or domestic installations. When the concentration is limited, the inhibitors may not avert localized corrosion such as pitting or the corrosion of galvanized steel, steel, cast iron, copper, or lead, sufficiently to extend the life of the system beyond 75-100 years. Corrosion inhibitors are useful when concerns about water quality deterioration have to be resolved. Unfortunately, there is no simple solution for balancing water quality, health risks, system reliability, and environmental impact. 

Another environmentally compatible primary explosive is copper(I) 5-nitrotetrazolate (Fig. 1.17). This compound has been developed under the name of DBX-1 by Pacific Scientific EMC and is a suitable replacement for lead azide. DBX-1 is thermally stable up to 325 °C (DSC). The impact sensitivity of DBX-1 is 0.04 J (ball-drop instrument) compared with 0.05 J for LA. The compound is stable at 180 °C for 24 hrs in air and for 2 months at 70 °C. DBX-1 can be obtained from NaNT and Cu(I)Cl in HC1/H20 solution at a higher temperature. However, the best preparation for DBX-1 in a yield of 80-90 % is shown in the following equation where sodium ascorbate, NaC6H706, is used as the reducing agent ... 

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