Leaching processes affecting

The solid sulfur product need not be chosen as an unknown. Near room temperature, only a small percentage of it is oxidized to soluble sulfur-containing anions(4). It can be assumed, therefore, that none of the sulfur atoms originally present in the solid chalcopyrite enter the solution. The sulfur product is not recovered in the leaching process and does not affect the solution chemistry. 

Radiolysis of the leachants by radiation from the glass does not affect the leaching process nor does it produce sufficient HNO3 to cause a pH decrease. 

In leaching, there usually is a very rapid leach rate that occurs when the mineral is on the surface of the particle, but many times the internal diffusion of the solid through the solid particle becomes controlling, and mixer variables do not affect the leaching rate beyond that point. In studying the effect of mixing on leaching processes, it is normally desirable to run separate experiments with... 

The inherent instability of sulfur-infiltrated concrete in aqueous media illustrated in this study may be the most important factor in utilization, because it will affect long-term durability of the concrete in many natural settings. The Ca(OH)2 produced by the hydration of portland cement is a principal reactant in the leaching process, and while it remains sulfur could be extracted, leaving the matrix vulnerable to other destructive processes. The removal rate of sulfur will vary greatly, depending mostly upon the pH of the immersion medium thus, the concrete deteriorates in alkaline sulfatic soils but is relatively stable in the corrosive neutral sulfatic solutions from the sodium sulfate plant. 

Process (i) is expected to be the major process affecting the dissolution of radionuclides present in the graphite lattice (principally or strongly adsorbed thereon. Processes (ii) or (ii) could result in more rapid leaching of the radionuclide than the graphite. 

Transport processes describe movement of the pesticide from one location to another or from one phase to another. Transport processes include both downward leaching, surface mnoff, volatilization from the soil to the atmosphere, as weU as upward movement by capillary water to the soil surface. Transport processes do not affect the total amount of pesticide in the environment however, they can move the pesticide to sites that have different potentials for degradation. Transport processes also redistribute the pesticide in the environment, possibly contaminating sites away from the site of apphcation such as surface and groundwater and the atmosphere. Transport of pesticides is a function of both retention and transport processes. 

During the first trials with synthetic separators around 1940 it had already been observed that some of the desired battery characteristics were affected detrimentally. The cold crank performance decreased and there was a tendency towards increased sulfation and thus shorter battery life. In extended test series, these effects could be traced back to the complete lack of wooden lignin, which had leached from the wooden veneer and interacted with the crystallization process at the negative electrode. By a dedicated addition of lignin sulfonates — so called organic expanders -— to the negative mass, not only were these disadvantages removed, but an improvement in performance was even achieved. 

These galvanic corrosion processes take place when one or more elemental constituents of an alloy is leached, often leaving a weak, porous structure, although the component dimensions often are unchanged. Dealloying particularly affects equipment constructed of cupronickels, bronzes, brasses, and gunmetal, such as FW heaters, strainers, valves, and pump impellers. 

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