Dear Dr. Vela:
I’d like to start a sustainability program recycling left over paraffin from burning candles at churches and cemeteries. Is there a methodology to bleach and eliminate the dirt?
Paraffin generally has a certain color after production, bleaching can be achieved through a filtering or hydrogenation process, the latter being the most widely used method.
Invest in a filter which will clean the paraffin without any problem. The picture below shows the color difference before and after being filtered.
The process involves mixing the paraffin with activated soil (activated charcoal will be more expensive) and letting it rest for a period of time. The time depends on the volume of paraffin that is being filtered. The paraffin is then pushed through the filter mesh, which collects the soil and impurities. This step could be repeated more than once depending on the color of the paraffin you’d like to achieve. The process is the same for colored candles (red, yellow, etc.) in most cases the result will not be completely white, due to the darker colors left from the use of aniline or dyes; which are not impurities as in the case of debris or the color that comes out of the de-oiling unit.
If you want to recycle colors, it is best to separate them accordingly to their tone and use the paraffin in colored candles with the same shades. This process needs to be adapted accordingly to your needs.