Sciencemadness Discussion Board

ultrasonic bath

scientistfromdarkness - 25-7-2006 at 04:01

Does anyone have this thing? It is very useful but not cheap. Write your comments on this please...

not_important - 25-7-2006 at 05:54

It can be pretty cheap, depends on size, frequency, and power level. How useful it is depends on what you are trying to do.

Lower frequncy low power is good for cleaning stuff. Amazing how quickly you can get gorp off of glassware. Used gear for this can be cheap.

Low intensity can help with reaction where there are several phases. I've used a conventional untrasound unit as an aid to hydrolysis of esters; the ultrasound gives good mixing of aqueous and nonaqueous phases, speeds things up. Helps with reactions where the is a metal, Grignard and Reformatsky for example, by cleaning the metal surface and possibly flaking off metal fragments. I've also used it to do mixed preciptation, several metal salts plus urea in water, heat and ultrasound to get mixed hydroxides/oxides/carbonates for ceramics. Gear may be more expensive; bigger tank, maybe one that lets you circulate the bath so you can heat or cool it - the low end equipment may not take hot water in the bath.

High intensity can do everything low intensity can and more. In some cases it seems to work as if the reaction was being run under pressure at higher temperature. Sometimes the reaction takes an unusual path. Don't really know much about this range, it takes the more expensive equipment.

scientistfromdarkness - 25-7-2006 at 07:01

what model and producer is your ultrasonis bath?

not_important - 26-7-2006 at 01:33

A well used second or third hand desk-top clearer unit. Previous owner cast small sculptures and used it for cleaning. No identifying markings left, part of the original case is gone and replaced with hand-bent metal sheet. Thus, I've no idea what it is or who made it, and I've never felt inspired to tear it open to see if there is any ID inside.

Again, what you should look for depends on what you want to do with it. High intensity units are expensive, as are frequencies above 40 KHz.

scientistfromdarkness - 26-7-2006 at 03:09

thanks anyway