As you prolly know, peracetic and performic acid in PURE form should never be heated above 110°C, that's why in the 15% H2SO4 hydrolisis step in the performic method it is adviced to use a waterbath, which can't go higher then 100°C by nature, and not use an oilbath, which accidently could be overheated. And the temp is adviced as not exceeding 80°C, for 2 to 3 hours.
Don't forget we work with diluted forms of peracids.
Links:
Perbenzoic acid and performic acid are mentioned as :
--- 3. Dangerous – When exposed to heat or flame may explode or is spontaneously flammable in air. In this link:
http://www.engr.usask.ca/dept/cen/safety.booklet/table.i.htm
Sadly there are no more details to gather on that page, but
you all should read this page and look for chemicals you already use or plan to use. It's better to read it before using them.
Using the Edit/Find(On this page) function of IE while filling in - per - will quickly give you an impression which peroxides or other per's are dangerous.
So we got interested to find a more detailed description of the dangers you asked for:
http://www.engr.usask.ca/dept/cen/safety.booklet/table.ii.htm
---List of Some Incompatible Chemicals
---Substances in the right hand column should be stored and handled so they cannot possibly accidentally contact corresponding substances in the left hand column.---
(Very handy and should be read by everyone here.)http://www.engr.usask.ca/dept/cen/safety.booklet/handling.chemicals.htm
In there I found this, amongst a heap of other good advice which can safe your life:
Listed below are a few simple, but important reminders of precautions that should be considered in the routine handling of reagents.-Before undertaking any chemical reaction always try to assess the hazards that may arise.
-Know the locations of safety showers, eye washes and the safety air packs and know how to use them.
-Keep reagent containers clean on the outside to protect your hands; use rubber or plastic gloves when appropriate.
-Be sure rubber gloves are clean on the inside before using; cleanse or decontaminate gloves regularly.
-Lab coats and closed-toed shoes should be worn to minimize hazards from splashes and spills.
-Avoid prolonged contact of chemicals with skin; wash hands and face frequently; be sure laboratory clothing is cleaned regularly.
-If water in not the appropriate washing agent, or antidote, procure proper first aid supplies before starting work.
-Avoid inadvertent contamination by not returning unused portions of reagents to stock bottles; stoppers should be held while pouring.
-Experiments involving toxic and corrosive vapours should be carried out in fume hoods. In general when working with small quantities of such materials the hood exhaust volume is sufficient to prevent an atmospheric pollution problem above and outside the building. When large scale operations are carried out in the fume hoods which evolve large amounts of either flammable, corrosive, or toxic vapours these vapours should not be simply vented to the outside but should be treated to destroy the harmful effects and thereby prevent atmospheric pollution outside the building.
-Condense flammable vapours and then dispose of the condensate. Other materials can be absorbed in an appropriate chemical solution.
-Never test chemical by taste.
-Smell cautiously - sniff (never inhale).
-Use a safety pipet filler, (pipeting by mouth is dangerous).
-Cool sealed vials of chemicals below the boiling point of the substance contained therein before breaking seal. Cool gradually, first in ice water, then CO2 etc., to avoid temperature shock to the glass vial and a possible explosion.
-Add concentrated chemicals to water (never vice versa).
-Low flash point liquids should be stored in safety cans.
-Limit quantities of solvents in glass bottles to one gallon.
-Keep flammable solvents such as benzene, ether, etc., away from hot plates and flames.
-Use care in transporting chemicals. The transporting of acids, liquids and hazardous solids to and from Stores is to be done using a pail or other carrier to retain the material if breakage occurs. This is to be strictly enforced by the Stores personnel.
-Use caution in working with mercury. The equilibrium concentration of Hg vapour over liquid mercury at room temperature is approximately 20 times the threshold toxic limit.
-Clean up spills of mercury and other chemicals promptly. (See SP-4 for cleanup procedure for mercury spills; see The Handbook on Laboratory Safety (located in the Thorvaldson Library for the method of cleanup of other chemicals).
PEROXIDES-Are a frequent cause of laboratory explosions.
-Common solvents that peroxidize easily include:
-Ethers – dioxane, tetrahydrofuran, ethylene glycol dimethyl ether (glyme), diethylene glycol dimethyl ether (diglyme), diethyl ether, diisopropyl ether;
-Alcohols – some secondary alcohols, for example, isoprophyl alcohol;
-Hydrocarbons – cyclohexene, also other olefins; tetralin, decalin, branched-chained saturated hydrocarbons, alkyl substituted cycloaliphatics.
-Since peroxide explosions occur most frequently during distillation they should be carried out behind shields.
-Such materials should not be stored over long periods of time because peroxides form readily in poorly closed containers or even in well closed containers if there is air space above the solvent.
-Solvents should always be tested for peroxide content before using.
-Text methods and procedures for removing peroxides are described in The Handbook on Laboratory Safety (
LT: a pinch of ferrous salt like ferrous chloride).
PERCHLORIC ACID-Do not use perchloric acid on wooden benches or tables.
-Keep the perchloric acid bottles on glass or ceramic trays having enough volume to hold all the acid in case the bottle breaks.
-Discoloured acid (contaminated) should be disposed of immediately.
-Acids should be diluted prior to being returned to Stores for disposal.
-Operations in which the acid is heated to fuming are forbidden in ordinary hoods. An acceptable fume hood for this operation
LT: should be specially build, including an explosion shield.
Am still searching for specific data on peracids, will return soon. LT/
WISDOMwillWIN
