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To Bleach Vegetable Oils (Another method pursued)

Another method pursued for bleaching oils is as follows: The oil is placed in a porcelain, stoneware, or well-tinned vessel, along with some dry filtering powder, 1 to 2 pounds to each gallon of the oil, or some dry and recently prepared hydrated alumina (to pound per gallon of oil; but much less is often sufficient if the article be of proper quality); and the heat of steam or boiling chloric acid, and keep the whole stirred for 2 days longer. Draw off the acid water, and wash the oil repeatedly with boiling water until all acid is removed from it. 1509. Engelhardt's Method of Bleaching Palm Oil. Heat 1000 parts by weight palm oil in an iron vessel to about 143° Fahr., and let it stand all night, sustaining the temperature. Next day pour it off into a clean vessel and let it cool down to about 100°.

Meanwhile, dissolve 15 parts bichromate of water being applied, is vigorously stirred, potash in 45 parts boiling water; when the with a clean wooden or stoneware spatula, solution has cooled a little, pour into it 60 for about an hour. It is then thrown into a parts hydrochloric acid. Add this mixture to Canton flannel oil-bag, and filtered, in the the palm oil, stirring quickly, and in about 5 usual manner, observing to return the run- minutes it will assume a sombre green color; nings until they become quite white and clear. by continued stirring the oil gradually clari- This is the way perfumers and wholesale fies and becomes quite limpid. It should druggists usually prepare their white almond become quite white after washing it with oil, white olive oil, and white oil of ben. For- warm water; but if not entirely colorless, the merly fresh burnt animal charcoal was chiefly operation must be repeated, using + part used for the purpose, and is still so employed bichromate of potash, and 1 part hydrochloric by some houses; but the other substances acid. This is a quick method, and Engelhardt answer better and are more convenient. claims that it produces better results than the (Cooley.)