Study On The Processes Of Separation Of Lanolin Saponification Resultants And Extraction Of Cholesterol

In the paper, the processes for extractions of cholesterol from crude lanolin and productions of lanolin alcohol and lanolin acid as byproducts were studied, and the processes of saponification resultants separation, complexing of cholesterol and crude cholesterol recrystallizing were focused on. The effects of every factor on yield and purity of products, and the suited process conditions were presented.On the base of former experiments, some improvements were made for total technology system more simple and reasonable. Balance calculationss of mass and heat were made, and main equipments types and technology costs were studied for the pilot plant. For the process of crude lanolin saponification, the C-water was changed to the C, so that the reaction velocity and saponification degree were improved, and the subsequence processes became more reasonable. The suited conditions were determined as follows: NaOH dosage of 1.8 times, reaction temperature of 78~79℃, reaction time of 8h. Then saponification degree can surpass 98%. In the separation of saponification resultants, the sodium soap of lanolin acid was converted to the calcium soap by Ca-C, which avoided emulsification in extraction and made separation easy, the complexing of cholesterol was limited through controlling the Ca-C dosage, which made subsequence separation simple. The suited conditions were determined as follows: Ca-C dosage of 1.5 times of theretical value, reaction temperature of 25℃, the ratios of A to lanolin respectively being 6 and 3, the extraction time being 30min and 15min respectively. Then the lanolin alcohol yield can reach about 65%. For the process of preparation of lanolin acid from the calcium soap, transform reaction of the calcium soap and extraction of lanolin acid carried simultaneously through, then that the reation velocity was improved and the transform degree and production quality were increased. The suited conditions were given as: reaction time of 2h, reaction temperature of 75℃, the ratio of Ca-C to water being 1, and pH 2.0~3.0. Under such conditions, lanolin acid yield can reach above 94%. For the purification process for complexing of cholesterol, change of complexing reagent from Ca-C to Ca-D improved complexing selectivity and cholesterol yield. The suited conditions were determined as: reaction time of 2h, the ratio of Ca-D to cholesterol being 6. For subsequent complex purification, the ratio of solvent to lanolin alcohol was 4.5, the ratio of B to A was 7, the lowering temperature was at 10℃/h, and the final cooling temperature was 20℃. For the process of recrystal of crude cholesterol, the suited conditions were given as following: the ratio of A dosage to crude cholesterol being 6, the final cooling temperature of 15℃.Under above suited conditions, with crude lanolin and reagent-grade lanolin as material, the lanolin alcohol yield was about 65% to lanolin, lanolin acid yield was above 94% to its original amount, product purity of the cholesterol exceeded 90%, and the total cholesterol yields were 60% to its original amount. And the quality of cholesterol accorded with USA NF standard as cosmetics additive.