Study On Synthesis Of Terpinolene From Industrial Grade Dipentene

In order to find a high value chemical usage approarch for the industrial grade dipentene,the preparation and representation for properties of solid superacids,the synthesis technology of terpinolene from industrial grade dipentene catalysized by home-made solid superacids,and the preliminary sepration technology of the synthetic product were studied in this academic dissertation.The main results obtained from the study are as follows:1.Two kinds of solid superacid,SO42-/ZrO2 and SO42-/ZrO2-Fe2O3,were prepared by the sedimentation-impregnation method.A kind of solid superacid,S2O82-/ZrO2,was prepared by the Sol-Gel method.Their optimized preparation technology were obtained.Their acid sthength were measured and their properties were represented by IR,XRD and SEM techniques.(1)The H0 value of the 3 kinds of home-made solid acid is all less than-11.93.There are superacid centers in their chemical structure showed by the IR and XRD results.The SO42-/ZrO2-Fe2O3has the strongest acidity.(2)The optimized preparation technology were obtained for the 3 kinds of home-made solid acid measured by the reaction effect for the preparation of terpinolene from industrial grade dipentene.The optimized technology for the preparation of SO42-/ZrO2 is obtined as follows:H2SO4 concentration 1.0 mol/L,soaking time 12 h with H2SO4,baking temperature 600 ?.The optimized technology for the preparation of SO42-/ZrO2-Fe2O3 is obtined as follows:iron and zirconium mass ratio 1.5:100,H2SO4 concentration 1.5 mol/L,baking temperature 600 ?.The optimized technology for the preparation of S2O82-/ZrO2 is obtined as follows:ammonium persulfate concentration 10%(m/m),ammonium persulfate/zirconium n-butoxide 1.5?2.0:1,Sol pH value 4?5,Gel temperature 80 ?,Gel time 2 h,baking temperature 550 ?.2.The terpinolene was prepared from the original industrial grade dipentene through a one-step reaction catalysized by the 3 kinds of home-made solid superacid.Under the optimized synthis technology obtained from the study,the terpinolene content in the synthetic product is almost equal to that obtained from a two-step reaction with high-quality pinene as original material in open reports.(1)The 3 kinds of home-made solid superacid all have prominent catalysis effects for the preparation of terpinolene from industrial grade dipentene.SO42-/ZrO2-Fe2O3has the best integrated catalysis property,and SO42-/ZrO2 takes second place.S2O82-/ZrO2 can promote the conversation of dipentene,but has low selectivity in the process of dipentene converting to terpinolene.(2)The optimized technology for the preparation of terpinolene from the original industrial grade dipentene catalysized by SO42-/ZrO2 is obtined as follows:catalyst dosage 5%(based on the mass of industrial grade dipentene),reaction temperature 110 ?,reaction time 4 h.The terpinolene content is up to 33.398%in the synthtic product under the optimized technology mentioned above.The optimized technology for the preparation of terpinolene from the original industrial grade dipentene catalysized by SO42-/ZrO2-Fe2O3 is obtined as follows:catalyst dosage 2%(based on the mass of industrial grade dipentene),reaction temperature 100 ?,reaction time 3 h.The terpinolene content is up to 33.117%in the synthtic product under the optimized technology mentioned above.The optimized technology for the preparation of terpinolene from the original industrial grade dipentene catalysized by S2O82-/ZrO2 is obtined as follows:catalyst dosage 5%(based on the mass of industrial grade dipentene),reaction temperature 100 ?,reaction time 3 h.The terpinolene content is up to 31.732%in the synthtic product under the optimized technology mentioned above.(3)Catalyst dosage,reaction temperature and reaction time are main influcing factors for the preparation of terpinolene from the original industrial grade dipentene catalysized by solid superacids.Reducing reaction time is necessary at high temperature in order to obtain high terpinolene content and high terpinolene selectivity,while avoiding excessive side reactions.3.The synthis products from the original industrial grade dipentene catalysized by solid superacids were seperated with rectification under vacuum method.The terpinolene content in the products is raised to 55%.High vacuum degree,high packing layer and smaller temperature interval for collecting fractions are good for improving the seperation effect.