Hazards from explosion reactive compounds

Two compounds are included in tins category of antimicrobials. One is tile gas, ethylene oxide, the other, propylene oxide. a colorless liquid with a boiling point of 35 0 Ethylene is highly reactive and must be used carefully and only with proper equipment. Somewhat less hazardous from an explosion standpoint, propylene oxide also has an explosive range of 2-22%. Consequently, these materials are usually mixed with inert substances, such as carbon dioxide or organic diluents. 

Acetylene is a reactive material that poses a fire and explosion hazard. Its lower and upper explosive limits in air are 2.5% and 93%, respectively. Acetylene reacts with active metals (e.g., copper, silver, and mercury) to form explosive acetylide compounds. Acetylene manufactured from calcium carbide can contain impurities such as phosphine and arsine that are responsible for the ethereal to garlic-like odor of commercial acetylene and pose a greater human... 

The reactivity of aliphatic amines is low. Strongly basic, these compounds react vigorously with concentrated mineral acids. The explosion hazards from amines are very limited. They may promote base-catalyzed polymerization of many unsaturated organics. Such reactions are exothermic and can become violent if not controlled properly. Reactions with perchloric acid, hypochlorites, and chlorine may produce unstable products that may explode. 

The subject of hazardous properties of chemical compounds constitutes a very wide area which includes topics of wide diversity ranging from toxicology and explosivity of a compound to its disposal or exposure limits in air. In fact, each of these topics can form a subject for a book on its own merits. There are several well-docnmented books on these topics. However, most of these works show important limitations. The objectives of this book, therefore, are (1) to present information on many aspects of hazardous properties of chemical substances, covering the research literature up to 1991, and (2) to correlate the hazardous properties of compounds to the functional groups, reactive sites, and other structural features in the molecules and thus to predict or assess the hazards of a compound from its structure when there is lack of experimental data. 

Active methylene compounds have been nitrated directly with nitric acid. Since the nitro group thus introduced also activates the carbon adjacent to it, the product resulting from the direct nitration of an active methylene compound is frequently highly reactive and consequently may be quite unstable—in fact, explosive. Therefore, as with all aliphatic nitro compounds, precaution must be taken to reduce the hazards of explosion to personnel and equipment. A typical example of the reaction is given in the following preparation. 

According to Klimov (Ref 2) the tetrafluoride is resistant to deton. However, because of its high reactivity, very sensitive explns result from contact with flammable materials such as acet, polyethylene, wool, paper, sawdust, Al foil, ferric carbonyl, lubricants or styrene Refs 1) J.H. Holloway, Noble-Gas Chemistry , Methuen, London (1968), 95 ff 2) BD. Klimov et al, Explosion Hazard During Work With Fluorine Containing Xenon Compounds , Zh Prikl Khim (Leningrad) 42 (12), 2822-24 (1969) CA 72, 85784 (1970) 3) T.C. 

Compared to other classes of organic compounds, ethers have relatively low toxicities. This characteristic can be attributed to the low reactivity of the C-O-C functional group arising from the high strength of the carbon-oxygen bond. Like diethyl ether, several of the more volatile ethers affect the central nervous system. Hazards other than their toxicities tend to be relatively more important for ethers. These hazards are flammability and formation of explosive peroxides (especially with di-isopropyl ether). 

Table 5.3.2.3 presents a compilation of examples of peroxidizable chemicals from several sources. (In this instance, peroxidizable means peroxide-forming, not capable of reacting with peroxide. ) This table does not list all the chemicals that could form dangerous concentrations of peroxides. Peroxide-forming compounds are often grouped based on their relative reactivity, as shown in Table 5.3.2.3. Group 1 chemicals are especially hazardous because they may form peroxides that can explode without concentration. Group 2 chemicals may form peroxides that explode upon concentration. Group 3 chemicals may spontaneously polymerize explosively with peroxide formation. There are other listings of chemicals that may form peroxides but do not fit into these groups. ...

---