| With the gradual depletion of fossil fuel resources and the increasing greenhouse effect, with the characteristics of being green, environmentally friendly, low-carbon and being renewable, biomass aviation fuel has become an potential alternative product to traditional fossil jet fuel with. Generally, the commonly used method for the preparation of aviation kerosene is two-step method, the first step is to change the unsaturated fats to be saturated fats by hydrogenation, and to obtain alkane by catalytic deoxygenation; the second step is to catalyze selective isomerization and cracking to product hydrocarbon-based products needed. The operation process of two-step method is much too complicated and high energy consumption is accompanied during this process, one-step ways direct access to high quality hydrocarbon-based fuels has been researched recently. The key step to realize of the process is to develop a bifunctional catalyst that is highly efficient in hydrodeoxygenation, cracking and isomerization. Therefore, this study used Jatropha oil as raw material and carried out more than 30 experiments, the final selection of the catalyst is Pt as the active metal, SAPO-11 as molecular sieves and modified with citric acid to the carrier. Jatropha oil catalytic reaction was conducted with this catalyst, and experimental results indicate that the deoxidation rate reached 99.3%, and the main deoxy-way is decarboxylation or decarbonylation, in the product the ratio of C8-C16 hydrocarbons reached 63.34%, and wherein the proportion of iso-paraffins is 21.31%.On the premise that the the catalyst was selected, with the raw materials of Jatropha oil and waste lard, single-factor experiment was carried out, the impact of the reaction temperature, hydrogen pressure, oil/catalyst, reaction time and stirring speed on the experiment was investigated. The best reaction conditions were determined by conducting the single factor experiment. For small Jatropha Curcas oil: reaction temperature, 290 ℃, hydrogen pressure, 2.5MPa, oil/catalyst, 10:1, reaction time, 3h, stirring speed, 200rpm; while for waste lard : reaction temperature is at 290 ℃, hydrogen pressure is 3MPa, oil/catalyst is 10:1, reaction time is 4h, stirring speed is at 150 rpm. The results of Jatropha Curcas oil obtained the best reaction conditions: isomerization rate is 19.01%, C8-C16 hydrocarbon is 69.2%; the results of waste lard : isomerization rate is 8.27%, C8-C16 hydrocarbon is 71.76%. Finally, waste lard is selected as representative material,the following optimization experiment was conducted by changing three factors which have significantly effects are: temperature, reaction time, stirring speed. A reliable model was obtained and the best corresponding reaction conditions were determined: The reaction temperature was 290.63℃, reaction time was 3.94 h, stirring speed was148.55 rpm, and it was under these conditions that the following experimental results can be obtained: the percentage of C8-C16 hydrocarbon is 70.29%, and isomerization rate is 8.86%. In order to verify the reliability of the model, test experiment at this condition was carried out and it was verified that in the aviation product obtained by catalyzing waste lard : C8-C16 is 73.86%, isomerization rate is 8.94%,which implies that the model is reliable, and it can be used to simulate experiment.
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