Peroxides removal from ethers

Low molecular weight ether hydroperoxides are similarly dangerous and therefore ethers should be tested for peroxides and any peroxidic products removed from them before ethers are distilled or evaporated to dryness. Many ethers autoxidize so readily that peroxidic compounds form at dangerous levels when stored in containers that are not airtight (133). Used ether containers should be handled cautiously and if they are found to contain hazardous soHd ether peroxides, bomb-squad assisted disposal may be required (134). ZeoHtes have been used for removal of peroxide impurities from ethers (135). 

Peroxides can be removed from ethers in a number of ways, including washing with solutions of ferrous ion (which reduces peroxides), or distillation from concentrated H2SO4 (which oxidizes peroxides). 

Mobile, very volatile, highly flammable liq. Vapor heavier than air. Characteristic, sweetish, pungent odor, more agreeable than chloroform. Burning taste. Tends to form explosive peroxides under the influence of air and light, esp when evaporation to dryness is attempted. Peroxides may be removed from ether by shaking with 5% aq ferrous sulfate soln. Addition of naphthols. polyphenols, aromatic amines,... 

Peroxides, removal from isoprene, 29,59 removal from isopropyl ether, 22,3 removal from o-tetrabne, 20, 95 Pexphthauc acid, mono-, 20, 70 Petroleum ether, 23,102, 104 Phenacyl chloride, 24, 25, 26 Phenanthrene, 28, 19 purification of, 28, 19 Phenanthrene-9-ai.dehvde, 28, S3 Phenanthrene, 9-bromo-, 28,19 9-Phenanthrenecarboniteile, 28, 7, 34... 

This reaction is catalyzed by sunlight. Thus ethers in the presence of oxygen or stored for a long period may contain peroxides. When evaporated to dryness, the concentrations of such peroxides increase, resulting in violent explosions. Tests for peroxides and the method of their removal from ethers are described in Section 18.3. 

Peroxides can usually be completely removed from a sample of ether by thorough shaking with aqueous potassium permanganate solution. 

The synthesis for each differs only in the relative proportion of monomer loaded into the reaction vessel. Commercial benzoyl peroxide (1 percent by weight based on the sum of TBTM and MMA) was employed as the initiator. 0.8 mol of TBTM freshly recrystallized from ether and 0.8 mol MMA were added to 860 g of benzene in a flask equipped with a thermometer and reflux condenser. To this mixture was added 4.3 g (0.018 mol) of benzoyl peroxide. The flask and contents were warmed at the reflux temperature of benzene (80.1°C) with stirring. After 24 hours reaction time the benzene was removed in vacuo at 50°C. 

Shutting down a process, either for an indefinite period of time or permanently, can introduce chemical reactivity hazard management considerations. For example, one facility wanted to dismantle some equipment for a process for which an ether was a feedstock. A review of facility records did not conclusively reveal whether the equipment had been thoroughly decontaminated after the process was shut down years before. This left open the possibility that the equipment might contain explosive peroxides that could have formed over time by peroxidation of the ether. In another example, an unstable byproduct exploded when piping removed from a process unit was being cut into smaller pieces for disposal. 

Oglialoro modification of, 708 Perkin triangle, 108, 218f Kon modification of, 109 Peroxides, detection of, in ether, 163 removal from diethyl ether, 163 removal from isopropyl alcohol, 886 Petroleum ether, purification of, 174 Phenacetin, 996, 997 1 10-Phenanthroline, 991, 992 p-Phenetidine, 997, 998 Phenetole, 665,670 Phenobarbitone, 1003,1004,1005 Phenol, 595, 613 Phenol aldehyde polymers, 1016 formation of, 1022 Phenolphthalein, 984, 985 action as indicator, 984 ... 

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