YT2095 Posted February 14, 2005 Author Posted February 14, 2005 my plan is to let it ALL evaporate and get "bone dry" so to speak. then re-dissolve the crystals in de-ionised water, filter and re-crystalise it. there`s not enough to waste at this time, I need the stuff and can`t wait for the delivery.
jdurg Posted February 14, 2005 Posted February 14, 2005 Yup. Potassium ethoxide is a light yellow powder which forms when a mixture of ethanol and KOH is slowly heated. The powder is moisture and air sensitive and will rapidly decompose into potassium hydroxide and ethanol. It can cause SEVERE burns if exposed to the skin or respiratory tract.
YT2095 Posted February 14, 2005 Author Posted February 14, 2005 Bugger! so what if it`s left to dehydrate 100%? will it decompose, or will my "Adding water after" idea work?
jdurg Posted February 14, 2005 Posted February 14, 2005 Adding water after will decompose it into potassium hydroxide and ethanol. So if you dilute with plenty of water, the ethoxide will go bye-bye.
budullewraagh Posted February 14, 2005 Posted February 14, 2005 either way the KI should come out as long as the solution is clear
budullewraagh Posted February 14, 2005 Posted February 14, 2005 btw a good way to finish this quickly and easily is to just make a chlorine apparatus and displace the iodide
YT2095 Posted February 14, 2005 Author Posted February 14, 2005 No, that`s Not the way I wish to go about this. I`ll gain nothing by "Cheating".
YT2095 Posted February 14, 2005 Author Posted February 14, 2005 erm, it`s Iodine Tincture, the Ethanol come with the package, as a Zero option thingy
budullewraagh Posted February 14, 2005 Posted February 14, 2005 just wait until the liquids evaporate. if the solution is clear you should have KI, even if there is some ethoxide. you will have ethoxide impurities. if you dilute, they will still form towards the end of your evaporation as long as there is an excess of KOH
jdurg Posted February 14, 2005 Posted February 14, 2005 You could also neutralize the solution by using hydroiodic acid, but that would almost be like cheating as well. (since the KOH would be neutralized to water and KI).
YT2095 Posted February 15, 2005 Author Posted February 15, 2005 well it was totaly dry this morning, there was indeed some KI in there and an equal amount of of these yellow crystals, so while the kettle was still hot from making my coffee, I added some to the flask, these yellow things do NOT want to dissolve at all, I`ve added more KOH and the ph is quite high now, I`m going to have to boil the liquid and see if they`ll dissolve and react that way. at least I know ONE way NOT to make KI edit: I just found this; http://www.business_services.oregonstate.edu/property/msds/DATA%5C6466.htm charming stuff!
ed84c Posted February 15, 2005 Posted February 15, 2005 This stuff sounds fiesty YT, have you been wearing protection up till now?
budullewraagh Posted February 15, 2005 Posted February 15, 2005 ethoxides are very hygroscopic and aren't stable in air, so i think your ethoxide decomposed. perhaps you should try an organic solvent. i once again implore you to try the Cl2 method
YT2095 Posted February 17, 2005 Author Posted February 17, 2005 I will next time, btw, I dumped the lot down the drain, even MY patience has its limits
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