Study On Process And Component Analysis For Volatile Oil Extraction From Dwarf Aromatic Camphor Leaves And Twigs

Taking dwarf aromatic camphor as the research object, the studies on the extraction of volatile oil from dwarf aromatic camphor leaves and twigs were carried out and the compositions of the volatile oil were analysed. The main contents include:1. Under certain technical conditions, the extraction component analysis and mechanism exploration of volatile oil extracted from dwarf aromatic camphor leaves and twigs were conducted by water distillation and microwave-assisted water distillation respectively. The experiment showed that when water distillation was used, the extraction efficiency, extraction time and component types of volatile oil are1.71%and0.33%,120min and90min,34and37respectively. The main component of the volatile oil is linalool and its mass percentage is separately64.31%and57.92%. And when microwave-assisted water distillation was used, the extraction efficiency, extraction time and component types of volatile oil are1.73%and0.35%,37.5min and90min,30and41, respectively. The main component of the volatile oil is linalool and its mass percentage is separately62.65%and56.81%. By the comparison of the two methods, their extraction efficiencies of volatile oil and the main components of the oil are similar. However, the extraction time of the latter is much less than that of the former, indicating that microwave-assisted water distillation is superior to traditional water distillation in time and energy saving. The mass transfer mechanisms of the two techniques are different, which is mainly the different directions of mass and heat transferes.2. Microwave-assisted water distillation was used to investigate the effects of microwave radiation time, microwave power and solid-liquid ratio on extraction efficiency of volatile oil from dwarf aromatic camphor leaves through single factor test. The experimental results showed that the most suitable technical conditions are: microwave radiation time37.5min, microwave power577W and liquid-solid ratio5:1mL/g, under which the extraction efficiencies of volatile oil, aromatic camphor and eucalyptus oil essence are1.73%,1.0843%and0.2439%, respectively. 3. On the basis of single factor experiment, microwave-assisted water distillation was used to, through the orthogonal test, further optimize the process conditions of volatile oil extraction from aromatic camphor leaves and analyse the influence degree of various factors on the extraction efficiency. The experimental results and intuitive analysis showed that the optimum technical parameters are microwave radiation time45min, microwave power577w and liquid-solid ratio5:1mL/g, under which the volatile oil extraction efficiency is1.74%. The variance analysis showed that the three investigation factors are all the factors which have no obvious effect on the objective function (volatile oil extraction efficiency), but their relative size of the influence degree are microwave radiation time (A)> solid-liquid ratio (C)> microwave power(B).4. Microwave-assisted water distillation was used to, through the response surface test, further optimize the extraction process and to establish a quadratic multinomial regression equation, which expresses the relationship between volatile oil extraction efficiency and the three investigation factors. The experimental results show that the optimal technical conditions are:microwave radiation time41.62min, microwave power579.35W and solid-liquid ratio4.69:1mL/g, under which, the volatile oil extraction efficiency is increased to1.75%. With the help of Design-Expert7.0software system for experimental data statistical analysis, and curve fitting, the mathematical model was established as follows:Y=-12.71584+0.067229X1+0.042130X2+0.36781X3-(6.94444E-006)X1X2-(3.33333E-004)X1X3+(1.04167E-004)X2X3-(7.40741E-004)X12+(3.65307E-005)X22-0.044167X32The model has a high stability and good agreement with experimental data and can be used to predict the extraction efficiency of volatile oil from dwarf aromatic camphor leaves under different conditions. The main effects of the three factors on the extraction efficiency are:microwave radiation time (A)> solid-liquid ratio (C)> microwave power (B). which is consistent with the results of orthogonal test.