Safety fluorination

Fluorine, the most reactive element known, is a dangerous material but may be handled safely using proper precautions. In any situation where an operator may come into contact with low pressure fluorine, safety glasses, a neoprene coat, boots, and clean neoprene gloves should be worn to afford overall body protection. This protection is effective against both fluorine and the hydrofluoric acid which may form from reaction of moisture in the air. 

Continuous monitoring for the presence of fluorine gas in the workplace may be accompHshed using detectors available from Mine Safety Apphances (Pittsburgh, Pa.) or FIT (Exton, Pa.). 

Hydrogen fluoride or compounds that can produce it and fluorine-containing oxidizers should be handled with adequate safety equipment and extreme care by weU-trained personnel. Often the effect of skin exposure is not immediately evident, especially when dilute solutions are handled. Pain may develop several hours later. 

Health and Safety Factors. Completely fluorinated alkanes are essentially nontoxic (16). Rats exposed for four hours to 80% perfluorocyclobutane and 20% oxygen showed only slight effects on respiration, but no pathological changes in organs. However, some fluorochemicals, especially functionalized derivatives and fluoroolefins, can be lethal. Monofluoroacetic acid and perfluoroisobutylene [382-21-8] are notoriously toxic (16). 

Health and Safety Factors. The toxicity of aHphatic CFCs and HCFCs generally decreases as the number of fluorine atoms increases (16), as shown in Table 7, but there are exceptions as in the case of 141b vs 142b. Also, some derivatives like HCFC-132b can have low acute but high chronic toxicides (29). 

Health and Safety Factors. Fluorocarbons containing bromine or iodine are more toxic than the corresponding chloro compounds. When the ratio of the fluorine to other halogens is high, the toxicity can be quite low, especially for bromofluorocarbons. Perfluoro-l-bromooctane [423-55-2] has an LD q of greater than 64 mL/kg when adininistered into the gastrointestinal tract, and has Htde effect when instilled into the lungs (49). Other examples are included in Table 7. 

As a leader in fluorine technology, Honeywell Chemicals is committed to safety, customer satisfaction, the development of new technology, and the manufacture and supply of fluorochemicals worldwide. We are proud to be the world s largest producer of hydrofluoric acid and sulfur hexafluoride supplying customers globally. 

As far as handling of fluorinating agents is concerned, no dramatic changes have occurred since the publication of Chemistry of Organic Fluorine Compound in 1976. Reiteration of basic safety regulations, however, is in order... 

Hazardous reactions are pointed out in specific cases. In addition general safety rules for work with fluorine and fluorinated agents are thoroughly discussed on pages 25 and 26 of this book and on pages 13 and 14 in the 1976/1992 editions. 

A Caution Hydrogen fluoride and fluorine are dangerous materials. Exposure to them will cause severe, painful, and perhaps fatal injury. Exposure may not be evident for several hours. The procedures described here pose the risk of exposure to hydrogen fluoride and to elemental fluorine and should only be carried out by, or under the direct supervision of, qualified professionals. Qualified first aid treatment and professional medical resources must be established prior to working in the area. Prompt treatment is necessary to reduce the severity of damage from exposure and should be sought immediately following exposure or suspected exposure. Material safety data sheets are available from HF and fluorine suppliers. Their recommendations should be followed scrupulously. 

Cleaning for fluorine service. It is important that materials that may contact elemental fluorine be thoroughly cleaned to remove any traces of grease or other substance that may ignite on contact with fluorine. Furthermore, it is important to passivate all surfaces that may contact fluorine. Refer to the manufacture s fluorine material safety data sheet for more information. The assembled anodes used in the laboratory were degreased by refluxing overnight with trichlorotrifluoroethane in an oversized Soxhlet extractor. 

Gezdhmte Chemie im Mikroreaktor, VDI Nachrichten, June 2000 Micro-reactor enterprises shape and material variety of micro reactors selectivity gains and new project regimes direct fluorination faster process development BASF investigations safety increase speed-up of catalyst development production for fine chemistry and pharmacy numbering-up first industrial examples for micro-reactor production [215]. 

DesMarteau, D. D. et al., J. Amer. Chem. Soc., 1987, 109, 7194-7196 Fluorine is the most electronegative and reactive element known, reacting, often violently, with most of the other elements and their compounds (note the large MRH values quoted below). Handling hazards and disposal of fluorine on a laboratory scale are adequately described [1,2,3,4,5][6], and a more general review is also available [7], Safety practices associated with the use of laboratory- and industrial-scale fluorine cells and facilities have been reviewed [8], Equipment and procedures for the laboratory use of fluorine and volatile fluorides have been... 

Partially fluorinated components can be used either as electrolyte solvents (Fig. 12) or as electrolyte additives (Fig. 13). In many cases they show much superior SEI forming capabilities compared to their non-fluorinated counterparts. Moreover, fluorinated solvents are in general much less flammable as less hydrogen is available, which might contribute to cell safety [12, 23, 25]. 

However, the fact that industrial applications of polymer surface fluorination employ a fluorine/nitrogen mixture as the fluorinating agent complicates matters because fluorine gas is toxic, may explode when brought into contact with organic substances, and causes severe bums on human tissue. Moreover, the use of fluorine requires highly qualified personnel and special safety systems. 

M.F.A. is practically odourless. When four of us were exposed to a concentration of 1/1,000,000 in a 10 cu.m, chamber, we were unable to detect the compound. Even at 1 /100,000 (30 sec. for reasons of safety) the compound was found to possess only a faint fruit-like odour indistinguishable from that of many harmless esters not containing fluorine. 

There have been far more thermochemical experiments carried out in fluorine than in any other halogen atmosphere, the large majority of them by fluorine bomb calorimetry [110-116]. Thus, only fluorine combustion calorimetry will be covered in this section with a strong emphasis on bomb calorimetry. Note, however, that many technical details and safety precautions mentioned here for fluorine combustion calorimetry also apply to combustion in other halogens. 

Safety precautions applicable to direct liquid phase fluorination of aromatic compounds are discussed [1]. Attention is drawn to the hazards attached to the use of many newer fluorinating agents [2], In a study of fluorination reactions of hafnium and zirconium oxides by the fluoroxidisers xenon difluoride, chlorine trifluoride and bromine trifluoride, reactivity decreased in the order given [3],... 

The survey of hazards and safety procedures involved in handling rocket fuels and oxidisers includes liquid hydrogen, pentaborane, fluorine, chlorine trifluoride, ozone, dinitrogen tetraoxide, hydrazine, methyl hydrazine and 1,1-dimethyl hydrazine [1]. The later volume [2] is a bargain compendium of five NFPA publications ... 

This section reviews these research efforts in the past decade on developing new solvents and lithium salts for nonaqueous electrolytes of lithium ion cells, but the cosolvents or additives developed for nonflammable electrolytes, most of which are phosphorus or fluorinated molecules, are not included, since their presence is intended for improvement in safety rather than performance. They will be reviewed in section 8.5. 

Historically, the so-called safety factor approach was introduced in the United States in the mid-1950s in response to the legislative needs in the area of the safety of chemical food additives (Lehman and Fitzhugh 1954). This approach proposed that a safe level of chemical food additives could be derived from a chronic NOAEL from animal studies divided by a 100-fold safety factor. The 100-fold safety factor as proposed by Lehman and Fitzhugh was based on a limited analysis of subchronic/chronic data on fluorine and arsenic in rats, dogs, and humans, and also on the assumption that the human population as a whole is heterogeneous. Initially, Lehman and Fitzhugh reasoned that the safety factor of 100 accounted for several areas of uncertainty ... 

Largent EJ Fluorine and compounds. In International Labor Ofiice Encyclopaedia of Occupational Health and Safety, Vol 1, A-K, pp 557-559. New York, McGraw-Hill, 1971... 

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