Posted By Robert K Lewis You will actually need to analyse the residues for any disposal to take place. It will almost certainly be covered as hazardous waste. Bob

Posted By Glyn Phillips The residue should be tested to try and establish the hazardous nature of the material. If you cannot do this 'in house' get in touch with a reputable waste disposal company (many out there) who can arrange the testing and subsequent disposal. In the mean time, ensure that the residue is stored in suitable containers and that they are marked with identifying information (date, source etc.) Since you currently have no specific information on the material, assume that is carries the same hazards as the original components.(corrosive and oxidising) Make sure they are stored away from flammables or other non compatable materials.

Posted By Jeffrey Watt Paul If it is NaOH (Sodium Hydroxide) nothing springs to mind as a new compound product resulting from the reaction with KMnO4 (Potassium permanganate). Manganese oxides are a black to brown-black colour. Potassium hydroxide will look like sodium hydroxide, white crystals. Best guess is that if the residue is white feathery crystals it is NaOH precipitating on the cold surfaces of the LEV. Corrosive and alkaline, a bit of wet universal indicator paper should turn deep blue on contact with the solid residue. Not a guarantee that it isn't something else but you are narrowing down the options. If you have normal procedures for disposal of sodium and potassioum hydroxide they may be appropriate but that is your decision Paul. Jeff