Ethylene ozone explosion

Carbon monoxide and ethylene admitted into contact with ozone via an aluminium tip ignited and burned smoothly, while normal contact of carbon monoxide, nitrogen oxide, ammonia or phosphine causes immediate explosion at 0° or —78°C [1], At pressures below 10 mbar, contact with ethylene is explosive at —150°C [2], See Nitrogen oxide, below... 

Ethylene forms explosive mixtures in air the LEE and UEL values are 2.7% and 36% by volume of air, respectively. Its reaction with fluorine is explosively violent (AH = —112 kcal/mol), and violent with chlorine (AH = —36 kcal/mol). In the presence of sunlight or UV light, an ethylene-chlorine mixture will explode spontaneously. The reaction is explosive at room temperature over the oxides of mercury or silver (Mellor 1946, Suppl. 1956). Ethylene reacts vigorously with oxidizing substances. It reacts with ozone to form ethylene ozonide, H2C(03)CH2, which is unstable and explodes on mechanical shock. Acid-catalyzed addition of hydrogen peroxide may produce ethyl hydroperoxide, which is unstable and explodes on heat or shock ... 

The sole possibility of preparing the two parent compounds of the trioxolane series consists in the action of ozone on ethylene. When this ozonation was performed under suitable conditions, e.g. in a condensed phase at temperatures below -175 °C, the formation of 1,2,3-trioxolane (1) was observed (72JA4856, 81JA2578) (cf. Section 4.33.2.2.4). However, because of its thermal instability, this primary ozonide cannot be isolated but rearranged at temperatures above -100 °C to 1,2,4-trioxolane (2), ethylene ozonide, a colorless, explosive liquid extremely sensitive to impact (42LA(583)187>. The mechanism of the ring transformation (1) -> (2) has been discussed in Section 4.33.3.1.2. 

Some gases explode by themselves without being mixed with other gases. For example, acetylene, ethylene oxide and ozone fall into this category. This property is recognized experimentally and no common evaluation method has been established. If the calculated decomposition heat of lg of the gas is large, it is assumed that the material may induce a decomposition explosion. 

At atmospheric pressure, when the mixture was admitted through the aluminum tip, no ignition took place with hydrogen, cyanogen, and methane (ozone rate 6 cc. per second). Carbon monoxide and ethylene, however, ignited spontaneously and burned normally afterwards without initiating an explosion or detonation in the ozone line. 

The limits, especially the upper limits, are slightly lower in smaller tubes due to the influence of the tube walls. The upper explosive limit of ethylene and air mixtures is raised from 16 per cent by volume of the hydrocarbon at 0 atmospheres pressure to 71 per cent at about 350 atmospheres pressure.32 It is probable that in the experiments with ozone to be described that the ozone acted as a trigger to set off the reaction which occurs with explosive violence when the proper mixtures of oxygen and ethylene are present.28... 

The application of ozone to the oxidation of ethylene was first investigated by Schonbein 88 in 1855 but neither he nor Otto who worked somewhat later,84 succeeded in isolating the primary product of the reaction because of the heavy explosions which invariably took place. 

The action of ozone on acetylene is very violent and explosions result when the reaction is conducted in the vapor phase. However, it is possible to study the mechanism of the reaction by carrying out the ozonization in solution. The ozonide formed in this way is too unstable to be isolated and only by allowing a very slow decomposition to occur by slow evaporation of the solvent is it possible to isolate reaction products. In this way, it has been found that the material remaining after evaporation of the solvent consists of a large proportion of glyoxal (SI per cent) and a small amount of formic acid (5.6 per cent).1,12 The decomposition of the ozonide of acetylene differs from that of ethylene in that the linkage of carbon to carbon is not destroyed. The direct oxidation of acetylene with ozone, however, results in die formation oi formic acid and carbon dioxide.188... 

VINYL NEODECANO ATE (51000-52-3) CijHjjOj Combustible, polymerizable liquid (flash point >175°F/>79°C). Inhibitor (monomethyl ether of hydroquinone or copper is recommended) must be present in adequate concentrations to avoid explosive polymerization. Inconq)atible with acids, 2-aminoethanol, ammonia, aliphatic amines, alkanolamines, ethylene diamine, ethyleneimine, ozone. The monomer is usually supplied in bulk or resin-lined drums and may be stored in tin- or stainless steel-lined dmms. Storage in plastic or other vessels is not recommended. The uninhibited... 

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