Cleaning up

There are a number of ways of emptying columns of silica for disposal and different research groups tend to have different approaches. For disposing of your column, run the solvent level down to the top of the sand and close the tap. Obtain a silica waste tub and invert the column over the tub. Open the tap and use an acetone wash bottle to gently let acetone dislodge the sand inside the column. The packing material will start to move and drop into the waste pot below. Once it is empty, wash the column in hot soapy water, rinse with water, then rinse with acetone and leave to dry.

Conical flasks used for the solvent mixture have usually only been exposed to pure solvents and do not require washing up. Pour away any remaining solvent into the waste stream and allow the residual solvent to evaporate in a fumehood.