Ideal packing for pot or reflux and pot still columns to enable the release of sulphide. The reasons that copper is often used for distilling are as follows: it is a great conductor of heat, it will remove sulphur compounds, and is an easy metal to work with. The main drawbacks of copper are higher cost and the fact that they are more difficult to keep clean. Copper absorbs sulphur compounds and yeast cells produced during fermentation and prevents the production of ethyl carbonate, a toxic chemical formed from cyanides. This stuff is totally undesirable in the distilled alcohol.