Storage, chemicals peroxide-forming

Safe Storage Period for Peroxide Forming Chemicals... 

Inspect and test peroxide-forming chemicals periodically (these should be labeled with an acquisition or expiration date) and discard containers that have exceeded their safe storage lifetime. 

A chemical that can rapidly bring about an oxidation reaction by supplying oxygen or receiving electrons during oxidation. Example nitric acid, CAS 7697-37-2 A chemical that can form peroxides upon storage conditions—peroxides are highly reactive and unstable, and can explode upon concentration or sudden shock. Example diisopropyl ether, CAS... 

Does this operation involve the use, storage, or generation of peroxide-forming chemicals, shock-sensitive chemicals, or picric acid ... 

Sorbic acid and its salts are highly refined to obtain the necessary purity for use in foods. The quaUty requirements are defined by the Food Chemicals Codex (Table 3). Codistillation or recrystaUization from water, alcohoHc solutions, or acetone is used to obtain sorbic acid and potassium sorbate of a purity that passes not only the Codex requirements but is sufficient for long-term storage. Measurement of the peroxide content and heat stabiUty can further determine the presence of low amounts of impurities. The presence of isomers, other than the trans,trans form, causes instabiUty and affects the melting point. 

This question pertains to substances that will react with the oxygen in the atmosphere to form unstable peroxides, which in turn might explosively decompose if concentrated. Peroxide formation, or peroxidation, usually happens slowly over time, when a peroxideforming liquid is stored with limited access to air. Substances that are peroxide formers will often have an inhibitor or stabilizer added to prevent peroxidation. They are often not easily identifiable as peroxide formers using MSDSs or International Chemical Safety Cards. They are often identified by another characteristic, such as flammability, for storage and shipping purposes. 

Official methods of chemical analysis of conventional diesel are often not adequate to characterize biodiesel. Tests for the levels of sulfur and aromatic components in biodiesel are useful but usually reveal that the concentrations of compounds containing these atoms or functional groups are very low. Analysis of biodiesel chemistry can reveal characteristics conferred by the source of the oU, the method of manufacture, and duration of storage (20, 21). For example, free and bound glycerol is measured to ascertain if biodiesel has been completely formed during synthesis. Fatty acid content, residual soaps, iodine value, peroxide value, and fatty acid composition all may reflect the quality of biodiesel (Table 1) but are unimportant and inapplicable in conventional diesel fuel quality determination. 

---