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Mike Bullivant's Diary

Day 11: Hand cream

Decide for the first half of this second day to repeat what we did yesterday, in an attempt to boost our yield of lanolin.

Kate helping MikeEverything goes to plan - sort of. As I start to reduce the solution down, the oily lanolin comes floating to the surface. The trouble is, there doesn't seem to be very much of it, and, what's more, it's a dark-brown oil - not yellow, as I expected. The dark colouration's down to impurities in the lanolin, and I suspect that I can purify it easily enough by repeatedly washing our recovered oil with hot water - but why is there so little of it? I then realize that I can force more lanolin out of solution by adding lots of table salt (sodium chloride) to the pot. This will make the water more ionic – something that organic fats and greases don't like. Sure enough, when I add the salt, heat the mixture up, and cool it down again, much more of the dark-brown oil floats to the surface. Success!

By the end of Day 2, we still don't seem to have extracted very much lanolin though. Then we realize that the wool that we'd been given looked suspiciously clean. More often than not, when you see a sheep, its coat is really dirty isn't it. We suspect this wool's been cleaned up, in which case much of the lanolin had already been washed out of it before we got to work on it. Ho hum! Still, we have enough of the impure, brown, oily stuff to work with tomorrow, and Kate H didn't actually specify how much hand cream she wanted. Just as well.

MikeTomorrow we have to purify the oil. It occurs to me that if I leave the pot containing the oil/water out in the cold overnight, the lanolin might just freeze out of the oil as a solid. The temperature here drops to minus 5 Celsius overnight, so it's worth a try. I leave the sawmill feeling more than happy with the way the second day's gone.

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