Precautions in use

The precautions needed flow naturally from the properties in addition to the precautions usual when handling any strong acid, it is necessary to ensure that perchloric acid does not come into contact with easily oxidisable organic matter or strongly reducing substances under circumstances where it can become hot or anhydrous. It is failure to observe these precautions that leads to problems, and a few examples of what to do and what not to do are given below — 

Having stressed some of the precautions to be taken, it is perhaps necessary to list the advantages of using perchloric acid, with particular reference to its use in wet oxidation procedure. 

Exposures to chemicals, resulting in toxic effects or oxygen-deficient atmospheres, may arise in a variety of industrial situations. A summary of common sources is given in Table 4.11 clearly this is not exhaustive since exposure may result whenever materials are mixed, machined, heated, dispersed or otherwise processed or used. 

The precautions naturally vary in each case. For example, to avoid improper admixture of chemicals will require  

Strategies for reducing the risk from toxic chemicals depend upon its nature (i.e. toxic, corrosive, dermatitic) and extent. A combination of the following measures may be appropriate. 

Hazardous chemicals or mixtures may be replaceable by safer materials. These may be less toxic per se, or less easily dispersed (e.g. less volatile or dusty). Substitution is also applicable to synthesis routes to avoid the use of toxic reactants/solvents or the production, either intentionally or accidentally, of toxic intermediates or byproducts. 

As a general rule, it is preferable to minimize the amounts of toxic chemicals in storage and in process. There may be an advantage in handling chemicals in the most dilute practicable concentration. 

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Hydrazoic acid reaction with cyclobu-tanecarboxyhc acid, 47, 28 Hydrogenation of t butylazidoacetate to glycme ( butyl ester, 46,47 Hydrogen bromide 46, 43 reaction with y butyrolactone, 46, 43 Hydrogen fluoride anhydrous, precautions in use of, 46, 3 in preparation of mtromum tetra-fluoroborate 47, 57 reaction with benzoyl chloride, 46,4 with boron tnfluonde in conversion of p cymene to m cymene, 47, 40 in bromofluorination of 1 heptene, 46, 11... 

The hazards and precautions in use of this very reactive fluorinating agent are outlined [1]. Contact with rubber, plastics or other organic materials may be explosively violent and reaction with moisture is very vigorous [2]. 

Patton, C. Thompson, S. Epel, D. Some precautions in using chelators to buffer metals in biological solutions. Cell Calcium 2004, 35, 427-431. 

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