Sigma-Aldrich Inhibitor Removers

Sigma-Aldrich Inhibitor-remover packings and ready-to-use, disposable prepacked columns conveniently remove small amounts of inhibitors which are added to reagents or solvents that would otherwise be unstable. R: 20-37 S: 22-38-36. Useful in applications which require that the stabilizer or inhibitor (hydroquinone (HQ), hydro-quinone monomethyl ether (MEHQ, 4-methoxyphenol), or 4-tert-butylcatechol (TBC) be removed prior to use. Columns may be discarded1 when exhausted or reused by filling column approximately 3/4 full with new packing material. HQ/MEHQ columns refill vol.: ~21g. TBC column refill vol.:~30g. Approx. column capacity: HQ/MEHQ: 3L at 100ppm.TBC: 4L at 15ppm.TBC columns and packings are not recommended for use with polar solvents, including acrylic acid. Vacuum distillation is suggested for such applications. Easy-to-use: Prewashing of prepacked glass columns with a small amount of monomer is recommended. Add monomer (or solvent) to an addition funnel which is secured above column. Add monomer dropwise to the column. Monitor rate of addition to prevent overflow of the column. Collect monomer in an appropriate container. For low-melting solid monomers, keep temperature of column above the melting point during use. Caution: Overheating may cause monomer to polymerize on the column. Viscous or high-melting monomers may be diluted in an appropriate solvent before addition to the column. Unused columns can be discarded with other solid chemical waste. After use, the toxicity and hazards of the monomer, from which the inhibitor is being removed, should be considered in deciding how to dispose of the packing material or column - SIAL (Additional S&H Or Hazmat Fees May Apply)