Toluene inflammation limit

The theoretical air required for the oxidation of toluene to benzoic add, 1.5 mols of oxygen per mol of tolnene, amounts to about 30 cn. ft. of air measured at 20° C. (6S° F.) and one atmosphere, per pound of toluene oxidized. Similarly, the theoretical air for oxidation to bcnzalcle-hyde amounts to 20 cu. ft. per pound of tolnene oxidized. The explosive limits of toluene at ordinary pressures and temperatures as measured in narrow tubes or small vessels are lower limit, 0.003375 lbs. toluene per cu. ft. air (296.5 cu. ft. air per lb. toluene) and upper limit, 0.01927 lbs. toluene per cu. ft. air (52 cu. ft. air per lb. toluene).1151 In the case of the lower aliphatic hydrocarbons as methane and ethane it is well known that the explosive or inflammability limits widen with rise in temperature so that it could well be expected that mixtures of toluene and air leaner than the one given for the lower limit and richer than the one for the upper limit would become inflammable as the temperature becomes higher. The same is true for increase in size of the explosion chamber. Hence, although theoretical mixtures of toluene and air for formation of benzaldehyde and benzoic acid lie on the rich side of the inflammable range,... 

Special attention must be given to the hazards involved in the use of solvents, and there is a general tendency to replace solvents that are hazardous, but have long been in use for historical reasons, with less dangerous solvents. For instance, benzene, a very useful solvent but known carcinogen, ought to be and actually often is replaced by the less hazardous toluene or xylene. Table A3 (see the appendices) provides some information concerning the toxicity of solvents on the table as well as their inflammability and the explosive limits of their vapor in air. 

Polyalumophenylsiloxane varnish is a solution of polyalumophenylsiloxane in a mixture of toluene and butanol. Its flammability, boiling point and inflammation point, as well as explosive limits of varnish vapours mixed with air, mostly depend on the properties of the solvents used. 

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