Thionyl chloride safety

Health nd Safety Factors. Thionyl chloride is a reactive acid chloride which can cause severe bums to the skin and eyes and acute respiratory tract injury upon vapor inhalation. The hydrolysis products, ie, hydrogen chloride and sulfur dioxide, are beheved to be the primary irritants. Depending on the extent of inhalation exposure, symptoms can range from coughing to pulmonary edema (182). The LC q (rat, inhalation) is 500 ppm (1 h), the DOT label is Corrosive, Poison, and the OSHA PEL is 1 ppm (183). The safety aspects of lithium batteries (qv) containing thionyl chloride have been reviewed (184,185). 

Lachrymator A lachrymator is an irritant that causes tearing (watering of the eyes). Examples include onions, tear gas, and pepper spray (capsaicin). Some typical lachrymating chemicals are thionyl chloride (SOClj) and acrolein (CHj=CH-CHO). Certain chemicals may say lachrymator on the label so treat these with respect. Use these only in a fume hood. Goggles or safety glasses are not adequate protection for lachrymators, because the fumes can still reach your eyes directly or through inhalation. 

Wang, S. S. Y., S. Kiang, and W. Merkl, "Investigation of a Thermal Runaway Hazard—Drum Storage of Thionyl Chloride/Ethyl Acetate Mixture," Process Safety Progress, 13, No. 3,153 (July 1994). 

Thionyl bromide, 23 647 Thionyl chloride, 23 642, 647-651 end use of chlorine, 6 135t commercial production of, 23 650 economic aspects of, 23 650 health and safety factors related to, 23 650... 

Equip the flask for vacuum distillation. Cool the receiving flask with an ice-salt bath, and attach the vacuum adapter to an aspirator by means of a safety trap such as that shown in Figure 2.42a. Evacuate the system and distill the excess thionyl chloride. When the thionyl chloride has been removed, cautiously release the vacuum. Tightly stopper the flask containing thionyl chloride. To the residue in the stillpot. which is 3,5-dinitrobenzoyl chloride, add 1 mL of the alcohol and 0.3 mL of... 

The addition of BrCl to the thionyl chloride cell enhances cell performance to increase the OCV to 3.9 V, operate over a wide temperature range, and provide an energy density up to 1,000 WhA. The structure of a typical BCX cell is shown in Fig. 9. Two layers of nonwoven glass separator are employed to provide added safety since this cell does not incorporate a safety vent. The glass-to-metal seal is designed to crack if an overpressure or over-temperature condition occurs. Cells are available in sizes from AA (2.0 Ah) to DD... 

Potential safety concerns with lithium-metal anodes and a flammable electrolyte. However, they have an excellent safety record in the field, and the safety of the solid cathode cells is generally regarded as being much better than that of lithium cells using liquid cathodes (thionyl chloride or sulfur dioxide) used primarily in industrial/military applications. These and other characteristics have made... 

As regards safety considerations, it should be noted that thionyl chloride is refluxed prior to addition of the fatty acid, whereas phosgene is passed in with the complete amount of fatty acid already being available. 

The Li/SOCl2 cell consists of a lithium anode, a porous carbon cathode, and a nonaqueous SOCl2 LLAlCl4 electrolyte. Other electrolyte salts, such as LiGaCl4 have been employed for specialized applications. Thionyl chloride is both the electrolyte solvent and the active cathode material. There are considerable differences in electrolyte formulations and electrode characteristics. The proportions of anode, cathode, and thionyl chloride will vary depending on the manufacturer and the desired performance characteristics. Significant controversy exists as to the relative safety of anode-limited vs. cathode-limited designs. Some cells have one or more electrolyte additives. Catalysts, metallic powders, or other substances have been used in the carbon cathode or in the electrolyte to enhance performance. 

A. Meitav and E. Peled, Calcium-Ca(AlCl4)2-Thionyl Chloride Cell Performance and Safety, J. 

Like the sulphur dioxide combination, thionyl chloride has been haunted by safety questions. One safety-related problem exists when a gas forms during the cell s operation, placing the cell under pressure. If heating occurs, there could be an explosion, or at least an output of toxic gases through the safety vents. 

Eagle Richer recommend their active lithium-thionyl chloride cells for micropower sources in advanced application areas, e.g. airborne instrumentation, undersea communications, mineral exploration, remote site monitoring safety controls, security, and space and/or defence systems. 

Hazardous incidents have been experienced with some lithium systems, particularly those using sulphur dioxide and thionyl chloride cathodes. These incidents generally occur at later stages in battery life under reverse current conditions, during voltage reversal and while operating at high temperatures. Safety incidents have not been experienced with lithium-iodine cells, which is why they power 90% of the cardiac pacemakers presently in use. 

The reserve configuration eliminates most safety concerns associated with lithium-thionyl chloride active batteries. 

---