Flammable organic solvent
Many organic solvents can cause fire or even explosion if not handled properly. The mixture of solvent and air spreads rapidly once it is burned. The firepower can ignite flammable objects in an instant, and it is ignited in places where oxygen is sufficient (such as the oxygen cylinder leaking), and the firepower is fiercer, which can burn some non-combustible substances. When the flammable organic solvent vapor is mixed with air and reaches a certain concentration range, an explosion may even occur.
When using flammable organic solvents, pay attention to the following:
(1) Place the container of flammable liquid on a lower reagent rack.
(2) Open the lid of the closed container when the container is kept closed and the liquid needs to be poured.
(3) Use flammable organic solvents in areas where there is no source of ignition and good ventilation (such as a fume hood), but be careful not to use too much.
(4) When storing flammable solvents, the storage should be reduced as much as possible to avoid danger.
(5) When heating flammable liquid, it is best to use oil bath or water bath, and do not use open flame heating.
(6) When using flammable organic solvents, special attention should be paid to the use temperature and experimental conditions. Table 1 shows the ignition point, auto-ignition temperature and combustion concentration range of commonly used organic solvents.
(7) Combustion of a mixture of chemical gas and air causes an explosion (for example, 3.25 g of acetone gas is equivalent to 10 g of explosive energy), so the combustion experiment requires careful operation.
(8) During use, beware of the following common sources of ignition: open flames (Bunsen burners, welding torches, oil lamps, fireplaces, ignition seedlings, matches), Mars (power switches, friction), heat sources (electric heating plates, filaments, electric heating sets, Oven, radiator, movable heater, cigarette), electrostatic charge.
                           
2. Toxic organic solvents
The toxicity of organic solvents is caused by local anesthesia stimulation or impaired function of the whole body when the solvent is in contact with the human body or absorbed by the human body. All volatile organic solvents, which are always toxic with long-term, high-concentration exposure to the human body, such as primary alcohols (except methanol), ethers, aldehydes, ketones, partial esters, benzyl alcohol solvents It is easy to damage the nervous system; methyl carboxylates and formates can cause lung poisoning; benzene and its derivatives, glycols, etc. will cause blood poisoning; halogenated hydrocarbons will cause liver and metabolic poisoning; tetrachloroethane And ethylene glycol can cause severe kidney poisoning. Therefore, you should pay attention to the following matters when using:
 
(1) Try not to directly contact the skin with organic solvents, so be sure to do personal protection. For details, see: Three Labs Personal Protection Knowledge.
(2) Pay attention to keep the experimental site ventilated.
(3) If the toxic organic solvent overflows during use, remove all sources of ignition according to the amount of spillage, remind the laboratory personnel to spray with a fire extinguisher, then use the absorbent to clean, bag, seal, and treat as a waste solvent. .