Oxygen chemical incompatibilities

A detailed strategy for the approach to safety testing is provided in Chapter 2 (Figures 2.3, 2.4, and 2.5) and in Chapter 3 (Figure 3.4). These schemes are directed to the investigation of thermal instabilities, chemical incompatibilities, including acid, water, and oxygen incompatibility, and other factors important to potential unstable behavior. 

DOT CLASSIFICATION 4.1 Label None SAFETY PROFILE Moderately toxic by ingestion, A severe eye and skin irritant. Mutation data reported. Flammable when exposed to heat or flame can react with oxidizing materials. To fight fire, use alcohol foam, CO2, dry chemical. Incompatible with liquid oxygen. Dangerous when heated to decomposition it emits toxic formaldehyde gas. See also FORMALDEHYDE. 

Compatibility with other system additives. This is another important requirement for the injection water biocide. The most common concern about chemical incompatibilities is an interaction between the biocide and the oxygen scavenger. Most commercially available biocides for oilfield use will react with the bisulfite based oxygen scavengers and become deactivated. This interaction will be discussed in greater detail in the discussion of the commonly used oilfield biocides. 

The reaction was reinvestigated by Cvetanovic (21) who found that within a small analytical uncertainty the exclusive primary step was reaction (11). Formation in this reaction of oxygen atoms in their triplet ground state (OIP) is required by the spin conservation rule and there is now ample chemical evidence that this is indeed so. A primary formar tion of an electronically excited N20 molecule, ruled out in the early work on spectroscopic grounds, is also incompatible with the lack of a pressure dependence of the rate of decomposition. 

Significant characteristics of the porphyrin iron monoxide are seen in the chemical reactivity. Naphthalene is converted initially to the corresponding arene oxide on treatment with P 450 (19), consistent with a molecular mechanism of oxygen transfer from an iron monoxide to the aromatic nucleus. Retention of stereochemistry in the P-450 catalyzed hydroxylation of d ethylbenzene also supports the molecular mechanism. The unusually large kinetic isotope effect observed for the P-450 oxidation of dideutero 1,3-diphenylpropane, kJkD = 11, demonstrates that C—H cleavage is involved in the rate determining step (20), probably in a very unusual environment, not incompatible with a molecular mechanism. 

Cadmium. Cadmium appears to be compatible or very mildly incompatible, similar to zinc. Almost nothing is known about which minerals it prefers. From a crystal-chemical view, cadmium has similar ionic radius and charge to calcium, but a tendency to prefer lower coordination due to its more covalent bonding with oxygen (similar to zinc and indium). Cadmium in spinel Uierzolites varies from 30 ppb to 60 ppb (BVSP) and varies in basalts from about 90 ppb to 150 ppb (Hertogen et al., 1980 Yi et al., 2000). Cd/Zn is —10 in peridotites (BVSP) and the continental cmst (Gao etal., 1998), and —1.5 X 10 in basalts (Yi etai, 2000). We adopt the mean of these ratios (1.2 X 10" ). 

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