Violent eruption

When hydroxide dissolves in water it gives off a lot of heat. If this operation is carried out without care the effects can be particularly dangerous. Hydroxide pellets were used. Then a stirrer was switched on. A very violent eruption threw out part of the reactor s content all over the surrounding area. 

Nitromethane had been stored with zeolites in order to dry it. More zeolites are added after several weeks. The resulting violent eruption was explained by the formation of sodium salt sediments. 

The preparation of ethyl cyanoacetate by the reaction of sodium cyanide on ethyl chloroacetate, which had not caused any incident after being carried out about twenty times, gives rise to a violent eruption of the medium during a further operation. No explanation could be provided. 

Probably polymeric at ambient temperature [1], at 400°C, traces of water react to cause a violent eruption and incandescence [2],... 

A bucket containing 25% sodium hydroxide solution was used to catch and neutralise bromine dripping from a leak. Lack of stirring allowed a layer of unreacted bromine to form below the alkali. Many hours later, a violent eruption occurred when the layers were disturbed dining disposal operations. Continuous stirring is essential to prevent stratification of slowly reacting mutually insoluble liquids, especially of such differing densities. 

Lack of any mixing arrangements caused stratification of strong sulfuric acid and (probably) sodium carbonate solutions in the same tank. When gas evolution caused intermixing of the layers, a violent eruption of the tank contents occurred. 

Interaction is violent [1]. A polythene-lined drum which had previously contained acetyl chloride was inspected and appeared empty, but when it was washed out with water a violent eruption occurred. This was attributed to trapping of residual acetyl chloride between the split liner and the drum wall [2], A very similar but more violent event, rupturing the drum and sending part of it 30 m. with sufficient force to puncture another drum which it hit, occurred in Scotland in 1997 [3],... 

The preparation of carbonylmetals by treating a transition metal halide either with carbon monoxide and zinc, or with iron pentacarbonyl is well-known and smooth. However, a violent eruptive reaction occurs if a methanolic solution of a cobalt halide, a rhodium halide or a ruthenium halide is treated with both zinc and iron pentacarbonyl. 

Meschino, J. A. et al., J. Org. Chem., 1971, 36, 3637, footnote 9 Interaction with dimethylsulfinate anion (from the sulfoxide and sodium hydride) at —5°C is very exothermic, and addition of the chloro compound must be slow to avoid violent eruption. 

Wilcox, C. F. et al., J. Amer. Chem. Soc., 1984, 106, 7196 It is more sensitive to thermal decomposition than other diazonium carboxylates, and will decompose readily when inadequate stirring, large scale or excessively rapid diazotisation produces too large a temperature rise. There is significant potential for violent eruption of suspensions, or detonation of the filtered solid, and all recommended precautions should be used. 

A mixture of the sulfide, ethylene glycol and hexane in a mantle-heated flask spontaneously overheated and exploded at an internal temperature of around 180°C. It had been intended to maintain the reaction temperature at 60°C, but since alcoholysis of the sulfide is exothermic, presence of the heating mantle prevented the dissipation of heat, and the reaction accelerated continuously until explosive decomposition occurred [1], An incident in similar circumstances involving interaction of the sulfide with 4-methyl-2-pentanol also led to violent eruption of the flask contents. 

Violent eruption, vulcanism the patient becomes violent, as he wakes up. The madness of the millennia breaks out Dionysius is violence."... 

Bromine. Addition of bromine to sodium hydroxide solution should be slow with adequate mixing to prevent the formation of two layers otherwise, a violent eruption may occur.2... 

Some operators who have been asked to wash out and prepare vessels for inspection or repairs understand these problems. Energetic reactions are likely with strong sulfuric acid, some salts like calcium chloride, and some alkalis. A violent eruption of steam and dilute caustic soda occurred when a preparing 73-percent caustic soda storage tank for maintenance. This incident appeared in the British Loss Prevention Bulletin about a decade ago. [6]... 

A Violent Eruption from a Tank Being Prepared for Maintenance... 

Drain cleaners are generally one of two types, sodium hydroxide or sulfuric acid. Numerous accidents have occurred when users have first applied one and, when it did not clear the drain, subsequently the other. The neutralization reaction of sodium hydroxide and sulfuric acid generates a large quantity of heat, sufficiently large enough to rapidly heat water present to its boiling point and result in a violent eruption. Numerous individuals have suffered eye and skin burns because of unreacted sodium hydroxide or sulfuric acid that has thus erupted. 

The wise practitioner of process development tries to stay informed of unexpected, hazardous reactions, which are often published as letters in Chemical Engineering News and other publications. Even transfer and storage operations should be considered. For instance, transferring a distillate of SOCl2 and EtOAc to drums that had contained SOCl2 seemed a safe method for short-term storage of the distillate. However, this storage led to pressure buildup and violent eruption, probably due to contact of the distillate with elemental zinc in the drum liners [20]. 

Only volcanoes characterized by particularly violent eruptive styles are likely to be important in producing the thin, widespread... 

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