Chemical hazards with peroxides

Volume 2 of Bretherick s Handbook of Reactive Chemical Hazards (Urben, 1999) lists many structures and individual chemical compounds having oxidizing properties. NFPA 432 can be consulted for typical organic peroxide formulations. Note, however, that some organic peroxide formulations bum with even less intensity than ordinary combustibles and present no chemical reactivity hazard. 

Label all chemical containers with hazard details and hazard warnings as flammable, corrosive, organic peroxide, oxidizer, pyrophoric, unstable (reactive), water reactive, combustible liquid, compressed gas, explosive, acids, and/or incompatible. 

SAFETY PROFILE Poison by intravenous and intraperitoneal routes. Mildly toxic by ingestion. Experimental reproductive effects. A skin and eye irritant. See also n-BUTYL ALCOHOL and ALCOHOLS. Dangerous fire hazard when exposed to heat or flame. Auto-oxidizes to an explosive peroxide. Ignites on contact with chromium trioxide. To fight fire, use water spray, alcohol foam, CO2, dry chemical. Incompatible with oxidizing materials. 

ASTM Saul Patai s book "The Chemistry of Peroxides" (41) was reviewed with some hope of finding either a systematic evaluation of reactivity as it relates to the potential hazard of peroxides or some basic concepts that would allow formulation of a unifying theory that would permit an algorithmic solution to the classification problem. Unfortunately, when Saul got to the chapter on safety he acknowledges that he gave up. Bretherick s "Handbook of Reactive Chemical Hazards" (42) presents some useful information and incident histories, but provides little in the way of coordinated insight based on molecular composition and structure to allow for systematic extrapolation to new materials. 

Because of the explosion risk associated with peroxides, older containers of ethers are not normally accepted as part of an ordinary hazardous waste shipment by a commercial chemical waste disposal firm. They would have to be disposed of as unstable explosive materials which is much more expensive than if the materials were not outdated. Any savings in buying the large economy size would be more than compensated for by the additional disposal costs. Attempting to treat the ethers to remove the peroxides or to dispose of them by laboratory persoimel carries with it the risk of an explosion and the subsequent liability for injuries. 

Table 5.3.2.3 presents a compilation of examples of peroxidizable chemicals from several sources. (In this instance, peroxidizable means peroxide-forming, not capable of reacting with peroxide. ) This table does not list all the chemicals that could form dangerous concentrations of peroxides. Peroxide-forming compounds are often grouped based on their relative reactivity, as shown in Table 5.3.2.3. Group 1 chemicals are especially hazardous because they may form peroxides that can explode without concentration. Group 2 chemicals may form peroxides that explode upon concentration. Group 3 chemicals may spontaneously polymerize explosively with peroxide formation. There are other listings of chemicals that may form peroxides but do not fit into these groups. ...

The most difficult polymers are thermoplastic polyolefins such as polypropylene and polyethylene. These have no obvious chemical handle. Some of the early work utilized the azide functionality, but this is a very hazardous group and no longer of commercial interest. More recent work uses unsaturation in combination with peroxide or possibly mechano-chemical grafting with the ultimate expression of this being to pregraft the inclusion reactive functional group onto the polymer or to copolymerize with it. 

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