Formaldehyde combustion product

Fire Hazards - Flash Point (deg. F) 482 CC Flammable Limits in Air (7o) Not pertinent Fire Extinguishing Agents Water, foam, carbon dioxide, or dry chemical Fire Extinguishing Agents Not To Be Used Not pertinent Special Hazards of Combustion Products Formaldehyde gas and ammonia may be given off when exposed to heat Behavior in Fire Not pertinent Ignition Temperature (deg. F) > 700 Electrical Hazard Not pertinent Burning Rate Not pertinent. 

Formaldehyde has been detected recently in the interstellar medium by microwave spectroscopy (593), It is a combustion product of hydrocarbons. The photolysis of H2CO by sunlight in the troposphere may produce H02 radicals by reactions such as... 

Formaldehyde, acetaldehyde, acetone, and carbon monoxide were common combustion products of the four hexanes. Propionaldehyde, n-butyraldehyde, acrylic aldehyde, crotonic aldehyde, and methyl ethyl ketone were all found as intermediates in the combustion of n-hcxane. Acetaldehyde and acetone were prominent and propionaldehyde and acrylic aldehyde were present among the intermediates from 2-methylpentane. Acetaldehyde and methyl ethyl ketone were peculiarly characteristic of 3-methyl-pentane and acetaldehyde, acetone, and pivalic aldehyde were characteristic of 2,2-dimethylbutane. In other words, the intermediate monocarbonyl combustion products... 

Aldehydes are often intermediates in the oxidation of other fuels [1—4, 29], and the ease with which they themselves oxidize and give rise to peroxidic materials or active radicals means that their role in these systems is likely to be important. For example, formaldehyde is produced during the oxidation of most hydrocarbons, and is known to behave as a branching intermediate during the high temperature combustion of methane [1—6], However, in certain systems, and particularly at lower temperatures, formaldehyde may behave as a retarder [7—9, 57]. Acetaldehyde is an intermediate in the oxidation of propene [10] and other olefins [11, 12], and its addition to these systems reduces the induction period or enhances the maximum rate. Many other examples are known both of the occurrence of aldehydes amongst the combustion products and of the ability of aldehydes to influence the oxidation of systems in which they occur [1, 13—19]. 

Urea-formaldehyde apparently, at least in some formulations, can produce highly toxic combustion products compared to other cellular materials. The University of Utah foimd it only slightly less toxic than phenolic foam, although with nonflaming combustion (830°C) it was found to be the fastest material to incapacitate test animals. Cyanide was found to be the causative agent of death. CO, CO2, and aimnonia are also produced in combustion, all of which are toxic. University of Pittsburgh studies showed UF foam to be only slightly less toxic than PTFE (solid, not foam) (6). 

On the other hand, formaldehyde is a byproduct of human activities. It is a combustion product it is in cigarette smoke, in wood combustion, and in natural gas flames. Urban air contains between 10 and 1,000 mg/m of aldehydes, depending on location. Typical concentrations are shown in Table I ... 

Indoor air pollution is caused by radon, a radioactive gas formed during uranium decay carbon monoxide and carbon dioxide, products of combustion and formaldehyde, a volatile organic substance released from resins used in construction materials. 

Further oxidation of CH3 proceeds by intermediate steps that are not entirely certain, involving formaldehyde, -CHO, and CO, which is finally converted to the ultimate combustion product, CO2, by the reaction... 

Carbon monoxide and carbon dioxide appearing in the combustion products are generated from the intermediate, formaldehyde in the oxygen-deficient zone ... 

Table 34-4. Mass Fraction of Combustion Products (ALD = Formaldehyde, Acetaldehyde, Butyraldehyde, Acrolein, etc.)...

Indoor Air Quality Control Techniques Radon, Formaldehyde, Combustion Products, Eds., W.J. Fisk, R.K. Spencer, D.T. Grimsrud, EJ. Offerman, B. Pedersen and R. Sextro, Noyes Data Corporation, Park Ridge, NJ, USA, 1987. 

There are several documented rational approaches toward the design of catalysts that are either entirely based on metal oxides or contain a significant metal oxide component. In particular, one area that demonstrates different methodologies for catalyst design is the selective partial oxidation of methane to methanol and formaldehyde. This transformation is one of the most challenging, as harsh conditions are often required to initiate reaction, whereas the desired products are thermodynamically unstable with respect to carbon oxide combustion products. Many catalyst systems have been evaluated, and although none exhibit exceptional performance, metal oxide-based systems are among some of the best. 

Volatile products of combustion phenol, formaldehyde, CO, CO, and more Wang, J Jiang, H Jiang, N, Ther-mochim. Acta, 496,136-42,2009. 

---