The Separation And Purification Of Effective Components In Waste Tobacco Leaves

Tobacco leave is an important economic crop,which has a large production and planting area.Thousands of compounds are found in tobacco leaves,which are widely used.For example,nicotine can be used to produce green and efficient pesticides;solanesol can be used to produce vitamin K2 and coenzyme Q10;rutin and chlorogenic acid can be used to produce related drugs;spices can be used to produce flavors and so on.However,about 25% of tobacco leaves in the tobacco industry are abandoned every year because they can`t be fully used.For example,nicotine,as one of the compounds with high content in waste tobacco,will cause serious environmental pollution.Therefore,we should make full use of these abandoned tobacco resources,which can not only increase the added value of waste tobacco leaves,but also play a role in environmental protection.In this paper,firstly,based on the original technology of the our research group,the process optimization was carried out.The precipitation method was used to replace ether extraction to prepare solanesol;the extraction method of rutin was added;the purification process of chlorogenic acid was optimized;and the combined extraction of solanesol,rutin,chlorogenic acid and nicotine was realized.The final process is: firstly,90% ethanol was used to extract the effective substances from tobacco leaves under 50?,and then extract solution was concentrated.The cooling filtration method is used to replace the original petroleum ether extraction method to obtain the oil containing solanesol.After saponification,solanesol with yield of72.3% and purity of 95.6% is obtained.The solution after solanesol separation is extracted with ethyl acetate to obtain the yield of 96.5% and the total crude chlorogenic acid with purity of about 15%.After the first purification with AB-8macroporous resin,the purity of total chlorogenic acid was about 65% and the yield was over 95%.After the second purification with Fpa98 CL ion exchange resin,neochlorogenic acid,the isomer of chlorogenic acid,could be separated.The yield of total chlorogenic acid was 70.1% and the purity was 82.4%.Rutin was extracted by isobutanol in ethyl acetate extraction phase,evaporated to butanol and precipitated.When it was concentrated to 0.5 times of the original volume,rutin with yield of73.2% and purity of 70.1% was obtained.The raffinate of butanol extraction was extracted by petroleum ether and saponified to obtain nicotine.Then,Aspen industrial accounting software was used to simulate and optimize the main energy consumption units(distillation ethanol,double tower distillation n-butanol and single-stage evaporation of ethyl acetate,n-butanol,and petroleum ether)in the process,so as to recover the heat of the ethanol distillation tower which consumes the largest energy.The optimal operating parameters are: theoretical platenumber 20,optimal feeding position 10,optimal reflux ratio 2.1,ethanol distillation under the system absolute 30 kPa,ethanol with purity of more than 95% and temperature of 50.2 ? was obtained on the top of the tower,and almost no ethanol is produced in the water phase of the tower;theoretical plate number 10 of n-butanol double tower,optimal feeding positions of water tower and n-butanol tower are 2 and2 respectively 9,the best reflux ratio is 0.01 and 0.1 respectively,and the absolute pressure of the system is 6 kPa.The purity of n-butanol and water solution is more than 99.9%.The absolute pressure of the single-stage evaporation system of ethyl acetate,n-butanol and petroleum ether is 30 kPa,10 kPa and 50 kPa respectively.Finally,the cost like:solvent cost,equipment cost,labor cost and energy consumption cost was accounted.Based on the calculation of producting 2000 tons of waste tobacco leaves every year,the net income of the production of crude products is10,843 million yuan,and the net income of the production of fine products is 49,243 million yuan.