Formaldehyde, Organic Peroxides

The changeover from ROO radicals to HOO radicals and the switch from organic peroxides to HOOH has been shown as temperature is increased in propane VPO (87,141). Tracer experiments have been used to explore product sequences in propane VPO (142—145). Propylene oxide comes exclusively from propylene. Ethylene, acetaldehyde, formaldehyde, methanol, carbon monoxide, and carbon dioxide come from both propane and propylene. Ethanol comes exclusively from propane. 

Many analytical techniques have been developed specifically for the analysis of engine exhaust gases with major emphasis having been placed on procedures for organic peroxides, hydrogen peroxide, formaldehyde, acetaldehyde, higher carbonyl compounds, acids, and various hydrocarbon compounds (31, 36, Jfi, 64, S3, 84, 105). The mass spectrometer also has been used successfully (100). 

During the induction period propionaldehyde and hydrogen peroxide are the main products, although a little acetaldehyde is also formed. At the end of the induction period the reaction accelerates autocatalytically and formaldehyde, methanol, carbon monoxide, methane and ethane together with acids and peroxides are formed. Hydrogen peroxide is the most abundant peroxidic product, but there are also appreciable amounts of organic peroxides and peroxyacids [17]. These reach concentrations (as does formaldehyde, and to a less marked extent the higher aldehydes) at the time of maximum rate. 

The oxidation of this alcohol takes place only above about 400 °C and is not preceded by an induction period [26]. The products are simpler than those formed during the oxidation of the other butanols. The fnain product is acetone, and there are smaller amounts of hydrogen peroxide, formaldehyde formed in the early stages. Later in the reaction, acetaldehyde, methanol and organic peroxides also appear. 

This ester oxidizes very easily [95], reaction being perceptible even below 140 °C. Above about 300 °C, pyrolysis to propene and acetic acid also takes place. It too, gives cool flames [47]. Fish and Waris [95] detected only acetone, organic peroxides and peroxyacids in the products. Between 280 and 360 °C, Hoare and Kamil [97] found a wider range of products including hydrogen peroxide, formaldehyde, methanol, isopropanol, acetic acid and at 320 °C and below, acetaldehyde. Propene and acetone were found at 360 °C but organic peroxides and peroxyacids were always absent. 

In cold polymerization, the most widely used initiator system is the redox reaction between chelated iron and organic peroxide using sodium formaldehyde sulfoxide (SFS) as a reducing agent [see Eqs. (1) and 2]. In hot polymerization, potassium persulfate is used as an initiator. 

Allergic contact dermatitis can be caused by epoxyresin compounds (Tarvainen et al. 1995), UP resin (Liden et al. 1984 Tarvainen et al. 1993a, 1995) and chemicals used as accelerators (cobalt) (Bourne and Milner 1963 Tarvainen et al. 1993b, 1995) or hardeners (organic peroxides) (Bourne and Milner 1963), as well as by p-tert-butylphenol formaldehyde resin (Tarvainen et al. 1993b) and various woods (Hausen and Adams 1990). Natural rubber latex in protective gloves has caused occupational contact urticaria (Tarvainen et al. 1993b). 

Disinfection destroys pathogenic organisms. This procedure can render an object safe for use. Disinfectants include solutions of hypochlorites, tinctures of iodine or iodophores, phenoHc derivatives, quaternary ammonium salts, ethyl alcohol, formaldehyde, glutaraldehyde, and hydrogen peroxide (see Disinfectants AND antiseptics). Effective use of disinfected materials must be judged by properly trained personnel. 

Formaldehyde, benzaldehyde and aniline react violently with 90% performic acid (Ref 1). An unspecified organic compd was added to the acid, and soon after the initial vigorous reaction had subsided, the mixt expld violently (Ref 3). Reaction with aikenes is vigorously exothermic, and adequate cooling is necessary. Reactions with performic acid can be more safely accomplished by the slow addition of hydrogen peroxide to a soln of the compd in formic acid (Ref 4)... 

Lee, M B. G. Heikes, D. J. Jacob, G. Sachse, and B. Anderson, Hydrogen Peroxide, Organic Hydroperoxide, and Formaldehyde as Primary Pollutants from Biomass Burning, J. Geophys. Res.,... 

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