PEROXIDE TEST STRIPS

Peroxide test strips may not be sufficiently reliable as the sole means of testing for presence of peroxides in a wide range of susceptible liquids. 

A sample of the readily peroxidisable allyl ether, tested with a peroxide test strip gave a negative test result, so was charged into a distillation apparatus, but there was a detonation during distillation. It was recommended that an additional test (potassium iodide-acetic acid) should be used unless it is certain that the test strips will give a positive result with a particular peroxide-containing liquid. 

The very sensitive ether peroxide test strips (Merckoquant, Art. No. 10011), available from E. Merck, Darmstadt, are used. If the test is still positive at this point, an additional 0.2 ml. of N-methyl morpholine is added. Stirring and heating at 75° are continued for another 5 hours. Remaining peroxide renders the work-up and drying of the product potentially hazardous. N-Methylmorpholine N-oxide (1) and hydrogen peroxide form a strong 1 1 complex. In the reaction with osmium tetroxide, this complex produces conditions similar to those of the Milas reaction,7 and some ketol formation may result. 

If the test is still positive, thiosulfate solution should be added until a negative test is attained. The checkers found EM Quant Peroxide Test Strips obtained from EM Science to be more sensitive than conventional Kl-Starch test paper. 

Hydrogen peroxide Acetone 4-Methyl-2-pentanone PEROXIDE TEST STRIPS PEROXIDISABLE COMPOUNDS Peroxomonosulfuric acid Acetone 2-Propanol Tetrahydrofuran See ETHERS... 

Commercially available peroxide. test strips (Aldrich Chemical Company, Inc.) are used to verify the presence of oxidizing agents. 

A technician was remotely handling an old, opened, metal can of anesthesia grade ethyl ether to add more ethyl alcohol as an inhibitor. Enough inhibitor was thought to be present, so the ether was not considered hazardous. The liquid level in the can was low so the technician had to tilt the can to pipette out an aliquot for the peroxide test strip. As the technician turned the can... 

E. Merck/EM Science, Merckquant Peroxide Test Strip, Postfach 41 19,... 

These test strips are available from EM Scientific, cat. No. 10011-1 or from Lab Safety Supply, cat. No. 1162. These strips quantify peroxides up to a concentration of 25 ppm. Aldrich Chemical has a peroxide test strip, cat. No. ZIO,168-0, that measures up to 100 ppm peroxide. The actual concentration at which peroxides become hazardous is not specifically stated in the literature. A number of publications use 100 ppm as a control valve for managing the material safely. 

Peroxide test strips, which turn to an indicative color in the presence of peroxides, are available commercially. Note that these strips must be air dried until the solvent evaporates and then exposed to moisture for proper operation. 

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