Solvents, flammable

HEXANE. Colorless, volatile liquid used as solvent, flammable. 

Solvent flammability, the solvent, and dust loading in the atmosphere of the working environment and of the products in the ease of edible materials are ihe main factors that conslilute health and safety hazards in extraction plants. General safely and environmental standards must therefore he applied and due recognition taken of Ihe most recently published national regulations relating to acceptable threshold limit values (TLVs) for solvents and dusts. 

MW 100.16 CAS [108-10-1] used as a solvent for gums, resins, oils, and waxes colorless liquid faint camphor-like odor boils at 117°C vapor pressure 7.5 torr at 25°C freezes at -87.4°C density 0.80 g/mL solubility in water 19.1 g/L, soluble in most organic solvents flammable. 

Note Moderately polar solvent soluble in water and most organic solvents flammable highly toxic by ingestion and inhalation absorbed through the skin may cause central nervous system depression, necrosis of the liver and kidneys incompatible with strong oxidizers. Synonyms diethylene ether, 1,4-diethylene dioxide, diethylene dioxide, dioxyethylene ether. 

Note Moderately polar solvent, ethereal odor soluble in water and most organic solvents flammable moderately toxic incompatible with strong oxidizers can form potentially explosive peroxides upon long standing in air see the relevant tables in the chapter on laboratory safety commercially, it is often stabilized against peroxidation with 0.5 to 1.0% (mass/mass) p-cresol, 05 to 1.0% (mass/mass) hydroquinone, or 0.01% (mass/mass) 4,4 -thiobis(6-ferf-butyl-m-cresol) can polymerize in the presence of cationic initiators such as Lewis acids or strong proton acids. Synonyms THF, tet-ramethylene oxide, diethylene oxide, 1,4-epoxybutane, oxolane, oxacyclopentane. 

It has been emphasized already that you should be familiar with the regulations and codes of practice pertaining in your laboratory. We will not discuss safety legislation here but some fundamental rules should be stressed. Never work alone in a laboratory. Always wear suitable safety spectacles and a cotton lab coat, and use other protection such as gloves, face masks, or safety shields if there is a particular hazard. Never eat, drink or smoke in a laboratory. Work at a safe, steady pace, and keep your bench and your lab clean and tidy. Familiarity breeds contempt do not allow yourself to get careless with everyday dangers such as solvent flammability. Familiarize yourself with the location and operation of the safety equipment in your laboratory. 

Nonaqueous solvents Flammability limits Fire hazard... 

Ease of solvent handling—e.gf., viscosity Solvent toxicity Solvent flammability... 

Conditions dry ether solvent (flammable, therefore no flames), under reflux with a trace of iodine as catalyst e.g. 

Closed floating-roof tank used to store polar-solvent flammable liquids, such as alcohols and ketones. 

The electrodeposition which is commercially most important is that of A1 by the NBS process . The plating bath is a mixed electrolyte solution of LiAlH. (0.2-O.4 M) and AICI3 (3 M) in anhydrous DEE. Attempts have been made to reduce the volatility of solvent (flammability), to improve the operating life of the bath, to increase the current density, and to find substitutes for LiAlH. ... 

Flammable solid inorganic, n.o.s., see Flammable Solids and Division 4.1, p.99 Flammable solvents. Flammable Liquids and Class 3, p.96... 

Two limits of solvent flammability exist. The lower flammability limit is the minimum eon-centration of solvent vapor in oxidizing gas (air) that is capable of propagating a flame through a homogeneous mixture of the oxidizer and the solvent vapor. Below the lower flammability limit the mixture is too lean to bum or explode. The upper flammability limit is the maximum concentration of solvent vapor in an oxidizing gas (air) above which propagation of flame does not occur. Mixtures with solvent vapor concentrations above the upper flammability limit are too rich in solvent or too lean in oxidizer to bum or explode. 

The ease of solvent handling also depends on odour, flammability, toxicity and environmental factors, some of which are again interlinked. The main factors governing the ease of handling are discussed separately in the chapters dealing with solvent flammability, safety, health and environmental considerations. The same applies to a certain extent to solvent stability. The industrial solvents discussed in this book are, as such, rather stable products. More reactive liquids such as olefins, acids, epichlorohydrin, many amines/ amides etc. are generally seen as reactants rather than solvents and are therefore not discussed further. 

Solvent flammability data can be obtained from many standard reference books [11,12,13]. However, the data quoted can often vary widely for the same solvent. This is mainly due to the different test methods that are used to measure what is nominally the same parameter. In addition, as explained above, small variations in composition can sometimes have a marked effect on the measured parameter. 

Introduction to solvents 3 4 Solvent flammability and reactivity hazards 70... 

Solvent consumption 5 4.2.4 Minimum oxygen concentration and inerting 4.2.5 Effect of different oxidants on flammability 4.2.6 Sources of solvent flammability data 75 76 77... 

Process safety (solvent flammability, combustibility and potential for explosion, potential for high emissions through high vapor pressure, static charge, peroxide formation, odor, etc.). 

Various organic solvents Flammability, toxicity, poor biodegradability, tendency to contribute to photochemical smog Supercritical Widely available, good solvent fluid carbon for organic solutes, readily dioxide removed by evaporation, nonpolluting, except as a greenhouse gas if allowed to escape ... 

Dispense solvents carefully to avoid spills. Make sure the receiving container is appropriate for the solvent — flammable solvents should only be transferred into approved safety cans. If you must transfer flammable solvents from a drum, make sure the drum is grounded and the pump and container are properly bonded. Never suck on a hose or pipette to siphon any solvent from a container. 

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