Copper in a marine environment

Mathematical Model for Simulation of the Fate of Copper in a Marine Environment... 

J. Sandberg, I. Odnevall Wallinder, C. Leygraf, and N. Le Bozec, Corrosion-induced copper runoff from naturally and pre-patinated copper in a marine environment, Corros. Sci. 48 4316 (2006). 

In another study focused on the shielding effects of buildings in a marine environment, the directional impact of marine aerosols was revealed by comparing the level of patina on CLIMAT s copper rod... 

Galvanic corrosion occurs when two metals or alloys having different compositions are electrically coupled while exposed to an electrolyte. This is the type of corrosion or dissolntion that was described in Section 17.2. The less noble or more reactive metal in the particular environment experiences corrosion the more inert metal, the cathode, is protected from corrosion. As examples, steel screws corrode when in contact with brass in a marine environment, and if copper and steel tubing are joined in a domestic water heater, the steel corrodes in the vicinity of the junction. Depending on the natiue of the solntion, one or more of the reduction reactions. Equations 17.3 through 17.7, occius at the surface of the cathode material. Figure 17.14 shows galvanic corrosion. 

Wang J, Foster N, Armalis S, Larson D, Zirino A, Olsen K (1995) Remote stripping electrode for in-situ monitoring of labile copper in the marine-environment. Anal Chim Acta 310 223-231... 

Interactions of trace elements with algae in the marine environment are being extensively studied (1-3, 5-12). Copper and zinc, both essential micronutrients required by phytoplankton, may be toxic at elevated concentrations (11-13). The biological effects of copper and zinc are strongly dependent on their speciation the activity of the free metal ion has been shown to be a key parameter (13). Toxic effects of Cu on marine algae have been observed in the range of pCu 10-12 (11-13). 

A mathematical model is formulated to describe the first-order kinetics of ionic copper released into a marine environment where sorption on suspended solids and complexation with dissolved organic matter occur. Reactions are followed in time until equilibrium, between the three copper states is achieved within about 3 hr (based on laboratory determinations of rate and equilibrium constants). The model is demonstrated by simulation of a hypothetical slug discharge of ionic copper, comparable to an actual accidental release off the California coast that caused an abalone kill. A two-dimensional finite element model, containing the copper submodel, was used to simulate the combined effects of advection, diffusion, and kinetic transformation for 6 hr following discharge of 45 kg of ionic copper. Results are shown graphically. 

Figure 8. Fate of copper in labile (O), complexed with DOM (D), and sorbed on SS (A) states following discharge to a marine environment...

A voluminous literature deals with heavy metals, particularly mercury, cadmium, lead, copper, and zinc in the marine environment [42]. The concentration of mercury, cadmium, and lead in open ocean sea-water are about... 

Miao, A.J., and W.X. Wang. 2007. Predicting copper toxicity with its intracellular or subcel-lular concentration and the thiol synthesis in a marine diatom. Environ. Sci. Technol. 41 1777-1782. 

Immersion tests in seawater at many places, some of which have exceeded 10 years, as well as more than 50 years of experience with marine applications of aluminium demonstrate that casting alloys without copper of the 40000 series A-S7G (42100), A-SIOG (43100) the 50000 series A-G3T (51100), A-G6 (51300), as well as wrought alloys of the 5000 and 6000 series have an excellent resistance to corrosion in the marine environment and seawater. 

Applications Ion implantation is widely employed to improve the life of tools. Thus press tools, dies and gear cutters can be treated to increase their durability by three times or more. Nitrogen-implanted tungsten carbide drawing dies for copper and iron wire can be improved up to fivefold. By implanting chromium, aluminium or silicon a considerable increase in the corrosion resistance of steel can be obtained. Implantation of chromium into aircraft bearing alloys has improved their durability in marine environments . 

Bordin, G., J. McCourt, and A. Rodriguez. 1994. Trace metals in the marine bivalve Macoma balthica in the Westerschelde estuary, the Netherlands. Part 2 intracellular partitioning of copper, cadmium, zinc and iron — variations of the cytoplasmic metal concentrations in natural and in vitro contaminated clams. Sci. Total Environ. 151 113-124. 

Casas, A.M. and E.A. Crecelius. 1994. Relationship between acid volatile sulfide and toxicity of zinc, lead and copper in marine sediments. Environ. Toxicol. Chem. 13 529-536. 

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