Chemical hazards with anhydrides

There are explosion hazards with phthahc anhydride, both as a dust or vapor in air and as a reactant. Table 11 presents explosion hazards resulting from phthahc anhydride dust or vapor (40,41). Preventative safeguards in handling sohd phthahc anhydride have been reported (15). Water, carbon dioxide, dry chemical, or foam may be used to extinguish the burning anhydride. Mixtures of phthahc anhydride with copper oxide, sodium nitrite, or nitric acid plus sulfuric acid above 80°C explode or react violently (39). 

There are explosion hazards with phthalic anhydride, both as a dust or vapor in air and as a reactant. Water, carbon dioxide, dry chemical, or foam may be used to extinguish the burning anhydride. 

DOT CLASSIFICATION 8 Label Corrosive DOT Class 8 Label Corrosive, Poison SAFETY PROFILE Confirmed human carcinogen. A poison. Moderately toxic by inhalation. A corrosive irritant to skin, eyes, and mucous membranes. A very dangerous fire hazard by chemical reaction with reducing agents and carbohydrates. A severe explosion hazard by chemical reaction with acetic acid, acetic anhydride, acetonitrile, acrolein, acrylic acid, acrylonitrile, aUyl... 

Production of Fertilizers and Compost (Table 13.4) Contact with Antigenic Plant Dust 286 Animal Proteins 286 Chemical Hazards 286 Metallic Dusts 286 Metal Working Fluid 287 Detergents 287 Epoxy Resin 287 Acid Anhydride 287 Compensation 287... 

Although I had been aware during most of my career as a preparative chemist of a general lack of information relevant to the reactive hazards associated with the use of chemicals, the realisation that this book needed to be compiled came soon after my reading Chemistry Industry for June 6th, 1964. This issue contained an account of an unexpected laboratory explosion involving chromium trioxide and acetic anhydride, a combination which I knew to be extremely hazardous from close personal experience 16 years previously. 

Chemicals that are water or air reactive pose a significant fire hazard because they may generate large amounts of heat. These materials may be pyrophoric, that is, they ignite spontaneously on exposure to air. They may also react violently with water and certain other chemicals. Water-reactive chemicals include anhydrides, carbides, hydrides, and alkali metals (e.g., lithium, sodium, potassium). 

ID S is synthesized by the reaction of ammonia with maleic anhydride in water. The synthesis of EDDS and IDS is also in accordance with the 3rd Principle of Green Chemistry Design Less Hazardous Chemical Synthesis, although they are still not perfectly green as there still some hazardous components. This can be a difficult principle to achieve completely as many reactive chemicals in the chemist s toolbox are often hazardous. 

Benzene is a volatile, colorless, highly flammable liquid that is consumed as a raw material for the manufacture of phenolic and polyester resins, polystyrene plastics, alkylbenzene surfactants, chlorobenzenes, insecticides, and dyes. It is hazardous both for its ignitability and toxicity (exposure to benzene causes blood abnormalities that may develop into leukemia). Naphthalene is the simplest member of a large number of multicychc aromatic hydrocarbons having two or more fused rings. It is a volatile white crystalline solid with a characteristic odor and has been used to make mothballs. The most important of the many chemical derivatives made from naphthalene is phthalic anhydride, from which phthalate ester plasticizers are synthesized. 

Flammable Liquid SAFETY PROFILE Mildly toxic by subcutaneous route. Questionable carcinogen with experimental tumorigenic and teratogenic data. A dangerous fire hazard when exposed to heat or flame can react with oxidizing materials. To fight fire, use foam, CO2, dry chemical. When heated to decomposition it emits acrid smoke and fumes. See also ANHYDRIDES. 

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