Safe handling considerations

Such outstanding advantages of TNT, its low sensitiveness to impact and friction, safe handling, considerable safety in storage (because of the low reactivity of the compound), relative safety in manufacture and relatively high explosive power, have made TNT the most widely used of all high explosives since the beginning of the twentieth century up to the present time. 

Toxicological properties of intermediates and impurities often dictate safe handling considerations on scale, as routine laboratory safety techniques may not transfer easily to the pilot plant and larger scales. Information on the safety of purchased chemicals may be found in the relevant MSDS. Intermediates prepared during processing may be hazardous to operators, and special handling may be... 

Syntheses of radioactive tracers involve all of the classical biochemical and synthetic chemical reactions used in the synthesis of nonradio active chemicals. There are, however, specialized techniques and considerations required for the safe handling of radioactive chemicals, strategic synthetic considerations in terms of their relatively high cost, and synthesis scale constraints governed by specific activity requirements. 

Prime considerations in pigment manufacture and use, as with any other chemical, include personnel safety, air emission and wastewater quality, and appropriate waste removal. Although basic information is supplied by the pigment manufacturer, it is the processor who is responsible for safe handling and use. He is also the one responsible for solving internal safety problems. 

These general objectives should form an extensive consensus. There is likewise a general consensus that environmental, occupational, health and consumer policies over the past thirty years have achieved considerable material success in reducing the use of known hazardous substances, also with regard to their loads in soil, air, water and products and not least of all with regard to their safe handling at the workplace. 

Compatability of ingredients is always important. Particularly important to safe handling is the autoignition temperature and friction sensitivity of the propellant. Small changes in the formulation can often effect these important properties. An example is the sensitivity of some propellant formulations to extremely small amounts of chlorate. Safety precautions must always include consideration of the chemistry. By following this practice, the propellant industry has experienced an excellent safety record while making unusual progress in the application of viscoelastic materials in case-bonded solid propellant rockets. 

CA UTION Since F2 is a highly oxidizing and toxic gas, experimenters should familiarize themselves with the precautions necessary for the safe handling of F2. The use of diluted F2 in an inert gas (N2 or argon) is considerably safer than pure F2. The apparatus used for the fluorination consisted of a 20% F2/N2 cylinder, a nitrogen cylinder, two flow meters, a Pyrex glass reactor, and valves made of stainless steel or brass. The cylinders, the flow meters, and the valves were connected with stainless steel or copper tubes. 

As noted in the preceding discussion of Sensitivity Data , TNT is comparatively insensitive and safe to handle. Consideration of the compilation of accident data (Ref 3) in Table 10 leads to the same conclusion. It is also noted that no one area is especially accident prone. The incident involving the expin of 10000 lbs is discussed in the section on Preparation portions of the plant were redesigned as a result. A Safety Data Statement (Ref 2) summarizes factors pertinent to its handling, shipping and use... 

With few exceptions, organolead compounds are sufficiently stable to air, water and fight to permit their safe handling without any unusual procedures. Because of toxicity considerations, however, organolead compounds should always be handled in well-ventilated hoods. (See Section 8). 

Industrial production of perfluorinated ionomers, Nafion membranes, and all perfluorinated membranes is costly due to several factors first, the monomers used are expensive to manufacture, since the synthesis requires a large number of steps and the monomers are dangerous to handle. The precautions for safe handling are considerable and costly. Secondly, the PSEPVE monomer is not used for other applications, which limits the volume of production. The most significant cost driver is the scale of production. Today, the volume of the Nafion market for chlor-aUcali electrolysis (150,000 m year ) and fuel cells (150,000 m year ) is about 300,000 m year resulting in a production capacity of 65,000 kg year. When compared to large-scale production of polymers like Nylon (1.2 x 10 m year ), the perfluorinated ionomer membrane is a specialty polymer produced in small volumes. 

Concentrating a large amount of a solution or a solid to dryness requires considerable time and is inefficient on a large scale. Commercial equipment is available for rotary evaporation of solutions in 100-liter flasks, but a half-filled 22-liter round-bottom flask is as much as most individuals can conveniently and safely handle without external support of the flask. On scale there is no immediate analogy to a rotary evaporator. Most concentrations are carried out in stirred vessels. 

Reductions often pose scale-up concerns. The primary difficulty is that hydrogen is used or generated, which requires additional considerations and equipment for safe handling. At the end of a reaction, safely quenching any residual reducing capability is a concern on scale. Work-up can be tedious, especially if colloidal salts are formed. Disposing of metal salt by-products can be costly, and environmental concerns arise. Considerable attention to details is necessary to develop a reliable reduction for scale-up. In spite of these potential drawbacks, once the process has been developed and the appropriate equipment has been commissioned, reductions can be extremely reliable. 

B. Special considerations required for safe handling of materials Yes/No... 

Many syntheses of (benzo)pyridazines involve the use of hydrazine and its derivatives, and the safe handling and disposal of these materials should be given careful consideration. Hydrazine and its salts are potential carcinogens and many hydrazine derivatives have, or are likely to have, toxic properties and all should be handled with care. In addition, hydrazine can react violently with oxidizing agents and the explosive decomposition of hydrazine vapor in air can be catalyzed by, for instance, rust. 

Safety. Alkylated products in themselves are not as a rule hazardous, although some of them, such as tetraethyllead, are toxic. However, some alkylating agents must be handled with considerable care, e.g., dimethyl sulfate. Among the catalysts, hydrogen fluoride is very toxic and hazardous, but the conditions for its safe handling have been worked out (see HF Alkylation), and consequently it may be employed without undue risk. 

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