Extraction Of Tea Seed Oil And Preparation Biodiesel From Tea Seed Oil

Tea seed is seed of tea tree （Camellia sinensis O Ktze）, it is a sideline product intea cultivation. The content of crude fat in tea seed is about30%, and tea seed oil iswhich extracted from tea seed. In order to better useful for tea seed and tea seed oil, oilextraction and preparation biodiesel were studied in this paper.Hexane as extraction solvent, tea seed oil was extracted wit ultrasonic-aid solventextraction method, according to single factor investigations, the optimization of tea seedoil extraction rate was obtained by using quadratic orthogonal rotation combinationdesign to study the effects of extraction temperature, material-liquid ratio, ultrasonictime. Using DPS6.50, it was found that the optimal process conditions were as follows:extraction temperature42℃, material-liquid ratio1:14（g:mL）, ultrasonic time42.9min,and that the resultant oil extraction rate was91.23%. The tea seed oil was light yellow,clear and transparent. Physical and chemical properties of tea seed oil were determined,including density, refractive index, water and volatiles content, acid value, iodine valueand saponification value. The water and volatiles content and acid value of tea seed oilwere lower, and the iodine value was less than100. The fatty acid components of teaseed oil was measured by gas chromatography/mass spectrometry（GC/MS）, showingcomponents of tea seed oil was palmitic acid, linoleic acid, oleic acid, stearic acid andeicosanoic acid, the content of oleic acid was higher.Homogeneous alkali KOH as catalyst, the ester exchange reaction preparationbiodiesel from tea seed oil was investigated. According to single factor investigation,transesterification ratio was established using Box-Behnken central compositeexperimental design to study the effects of reaction temperature, catalyst dosage,reaction time and mole ratio of methanol to oil. Using SAS8.1, it was found that theoptimal process conditions were as follows: reaction temperature58℃, catalystdosage（mass percent to oil）1.05%, reaction time66min, mole ratio of methanol to oil9.7:1, and that the resultant transesterification ratio was98.79%. Physical and chemicalcharacteristics of biodiesel were determined, including density, acid value, iodine value,water content, cetane index, flash point, heat value and viscosity, it was found that thebiodiesel could replace0#diesel and more security, the quality indexes of biodiesel inthe experiment reached the national biodiesel standards of Chinese. The characterizationof fourier transform infrared spectroscopy show that the eater exchange reactionproducts were the fatty acid methyl esters, and GC/MS show that the oleic acid methylester was higher in biodiesel.The reaction kinetics of ester exchange reaction preparation of biodiesel from teaseed oil was studied. The experimental results show that the reaction order of esterexchange reaction of tea seed oil is1.3, at60℃the reaction rate is0.6637（mol/L） min^-1 and at70℃is0.4872（mol/L） min^-1, the reaction activation energy is29.22KJ mol-1andfrequency factor is2.5×104（mol/L） min^-1. Reaction kinetics equation for:With homemade biodiesel as raw materials, emulsion biodiesel and micro-emulsion bisdiesel were prepared. Using Span-80as emulsifier, at emulsifier dosage1.5%, water content15%, stirring speed3000r/min, stirring time10min, a kind ofemulsion biodiesel with ivory, opaque was prepared. Using Span-80and Tween-80asemulsifier, ethanol as help solvent, at HLB6, emulsifier dosage10%, water content4%,a kind of micro-emulsion with colorless, transparent was prepared. Physical andchemical characteristics of products were determined, including density, cetane index,flash point, heat value and viscosity, the results show that products were complies withfuel oil requirements.