| The development of air transport industry and the increasingly serious environmental problems have forced the world to research the development of bio-aviation fuel. In the process of oil hydrogenation deoxidation and isomerization for preparation of bio-aviation fuel, noble metal catalysts synthesized with Pd, Pt and other were used as catalysts, and which were easily affected by the impurities P, N and metal ions. At present, the raw material used for preparation of bio-aviation fuel is mainly non edible vegetable oil in our country, and which contains pectin, mainly phospholipids. Therefore, the non edible vegetable oil degumming pretreatment has become the urgent problem to be solved in the process of the preparation of bio-aviation fuel.With Jatropha oil, castor oil and rubber seed oil as raw material, the influence of citric acid addition amount, temperature, adsorption(activated carbon) agent dosage, stirring speed, acid treatment time, MEA added amount, water amount and MEA processing time eight factors on the phosphate content of Jatropha oil and castor oil was studied. The rubber seed oil contains a small amount of rubber and has high acid value, the effect of the addition of citric acid for the removal of gelatinous is not obvious, and the presence of rubber will clog the filter pore when filtering. Therefore, the rubber seed oil degumming pretreatment experiment did not add citric acid and adsorbent(activated carbon), only investigated the influence of MEA added amount, water amount, temperature, stirring speed and reaction time 5 factors. Through single factor experiment, the best experimental conditions for the degumming pretreatment of the three kinds of raw material were determined as follows:(1)The optimal conditions for the degumming pretreatment of Jatropha oil are: the amount of the mass fraction of 45% citric acid added is 2% of the weight of oil, temperature is 50℃, the amount of added water is 2% of oil by weight, stirring speed is 250r/min, adsorption dosage is 2%, acid treatment time is 40 min, MEA added amount is 0.5% of the weight of oil, MEA treatment time is 30 min. Under these conditions, the phosphorus content of Jatropha oil can be reduced to below 1mg/kg, degumming rate is 98.94%.(2)The optimal conditions for the degumming pretreatment of castor oil are: the amount of the mass fraction of 45% citric acid added is 2% of the weight of oil, temperature is 70℃, the amount of added water is 3% of oil by weight, stirring speed is 250r/min, adsorption dosage is 2%, acid treatment time is 30 min, MEA added amount is 0.6% of the weight of oil, MEA treatment time is 40 min. Under these conditions, the phosphorus content of castor oil can be reduced to below 2mg/kg, degumming rate is 97.91%.(3)The optimal conditions for the degumming pretreatment of rubber seed oil are: MEA added amount is 2.5% of the weight of oil, temperature is 60℃, the amount of added water is 2% of oil by weight, reaction time is 40 min, stirring speed is 200r/min. Under these conditions, the phosphorus content of rubber seed oil can be reduced to below 3mg/kg, degumming rate is 91.37%.Determined the impact of factors and levels on the basis of single factor experiments, the Design Expert8.05 software was applied to optimize the experimental conditions for the degumming pretreatment of jatropha oil, castor oil and rubber seed oil, predicted by the model, in experimental study for the degumming pretreatment of jatropha oil,when citric acid added is 2.12% of the weight of oil, stirring speed is 258.47r/min, acid treatment time is 39.03 min, MEA added amount is 0.52% of the weight of oil, MEA treatment time is 26.23 min, the predictive value of the phosphorus content is 0.61 mg/kg. Carried out verification experiment under this condition, the phosphorus content of the resulting degumming oil was 0.65 mg/kg, with the predicted value of the difference between the 0.04 mg/kg, the gap is very small, indicating the model is reliable and can be used to simulate Jatropha oil degumming pretreatment experiments.In experimental study for the degumming pretreatment of castor oil, when citric acid added is 2.25% of the weight of oil, MEA added amount is 0.59% of the weight of oil, temperature is 68.62℃,MEA treatment time is 38.06 min,acid treatment time is 33.17 min, the predictive value of the phosphorus content is 1.35 mg/kg. Carried out verification experiment under this condition, the phosphorus content of the resulting degumming oil was 1.83 mg/kg, with the predicted value of the difference between the 0.48 mg/kg, the gap is very small, indicating the model is reliable and can be used to simulate castor oil degumming pretreatment experiments.In experimental study for the degumming pretreatment of rubber seed oil, when MEA added amount is 2.50% of the weight of oil, reaction time is 34 min, stirring speed is 280r/min, the predictive value of the phosphorus content is 2.26 mg/kg. Carried out verification experiment under this condition, the phosphorus content of the resulting degumming oil was 2.79 mg/kg, with the predicted value of the difference between the 0.53 mg/kg, the gap is very small, indicating the model is reliable and can be used to simulate rubber seed oil degumming pretreatment experiments.
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