Study On The Technologies Of Lanolin Saponification And Cholesterol Extraction From The Resultants

In the paper,the technologies for extracting cholesterol from crude lanolin were studied,and processes of lanolin Saponification,separation of lanolin alcohol from the calcium soap of lanolin fatty acid,complexing of cholesterol with CaCb and the complex hydrolysis for the preparation of cholesterol were focused on. The effects of every factor on yield and purity of product,and the suited process conditions were also presented. Purity,grease indexes,color reaction and m.p. of the product were analyzed,which showed that the yield of product can exceed 70%,and the purity can go beyond 90%,each index according with relevant cosmetics additive standard. Since lanolin is a cheap and easily gained material,and the extracted cholesterol is of high added value,this study has great value for industrialization.For the process of crude lanolin Saponification,the effects of material-feeding methods,addition of assistants,alkali dosage,reaction temperature and time on Saponification degree were studied. The suited conditions of this process were determined as follows:method of feeding lanolin into alkali-ethanol solution,NaOH dosage of 1.8 times of theoretical value,ethanol as assistants with concentration of 80%,reaction temperature of 77-78. Under such process conditions,when reaction time is 8h,Saponification degree can surpass 98%.In separation of lanolin alcohol from the calcium soap of lanolin fatty acid in Saponification resultants,the sodium soap of lanolin fatty acid was converted tocalcium soap by CaCla,and then the mixture was separated by extraction. Experiments showed that operation was easy with this method,and the losses in the separation could be greatly reduced. Effects of CaCh dosage,reaction temperature,extractive solvent and its dosage on the yield of lanolin alcohol were investigated,and the suited conditions of this process were obtained as follows:the ratio of CaC to lanolin material being 0.11:1,reaction temperature of 25 ,ethanol as extractive solvent for lanolin alcohol,and the ratio of ethanol to lanolin being 12:1. Under such conditions,lanolin alcohol yield can reach about 45% (based on crude lanolin).During complexing between lanolin alcohol and CaCk,three important factors of CaCb dosage,complexing temperature and complexing time were investigated with orthogonal method,and the suited processes conditions were given as:the ratio of CaChto cholesterol being 7:1,complexing time of 3h,complexing temperature of 78 ,and the effect degree on process being:reaction time>complexing temperature >ratio of CaCfeto cholesterol. The suited conditions for complex purification were also got as:petroleum emer-ethanol mixture as purification solvent,the ratio of solvent to lanolin alcohol being 4.3:1,the cooling temperature of 15.As for complex hydrolysis and cholesterol preparation,various hydrolysis methods and recrystallization solvents for hydrolysis product were compared,respectively. The experiments showed that the hydrolysis merely with water was more practicable. And the suited conditions were presented as:hydrolysis temperature of 15,the ratio of water to complex being 100:1,ethanol as recrystallization solvent. Under such process conditions,the yield of cholesterol can come to about 74% (based on cholesterol in lanolin alcohol).Finally,repetitive experiments were conducted under suited conditions above,with crude lanolin and reagent-grade lanolin as material. Product purity of the both exceeded 90%,and the total cholesterol yields were 70% and 74% respectively.